description of cretaceous sedimentary sequence ofthe second and third member of the...

RESEARCH PAPER

EARTH SCIENCE FRONTIERS Volume 16, Issue 2,March 2009 Online English edition of the Chinese language journal

Cite this article as: Earth Science Frontiers, 2009, 16(2): 288–313.

Received date: 21-Nov-2008; Accepted date: 23-Dec-2008. Corresponding author. E-mail: [email protected]

Foundation item: Supported by the National Basic Research Program of China (No. 2006 CB701403) Copyright © 2009, China University of Geosciences (Beijing) and Peking University, Published by Elsevier B.V. All rights reserved. DOI: 10.1016/S1872-5791(08)60080-9

Description of Cretaceous Sedimentary Sequence of the Second and Third Member of the Qingshankou Formation Recovered by CCSD-SK- s Borehole in Songliao Basin: Lithostratigraphy, Sedimentary Facies and Cyclic Stratigraphy WANG Pujun1, , GAO Youfeng1, CHENG Rihui1, WANG Guodong1, WU Heyong2, WAN Xiaoqiao3,

YANG Gansheng4, WANG Zhongxing2

1 College of Earth Sciences, Jilin University, Changchun 130061, China

2 Institute of Exploration and Development of Daqing Oilfield Company Ltd., Daqing 163712, China

3 School of Earth Sciences and Resources, China University of Geosciences (Beijing), Beijing 100083, China

4 School of Engineering, China University of Geosciences (Beijing), Beijing, 100083, China

Abstract: The second and third member of the Qingshankou Formation recovered by CCSD-SK- s borehole (China Cretaceous Continental Scientific Drilling-Songke -the south borehole) is 415.61 m long and 100% of cores recovery. The age of the member corresponds approximately to the Coniacian. The sequence and process of lithology-lithofacies and cyclic stratigraphy were revealed by a detailed core description. 12 rock types and 2 kinds of sedimentary subfacies including semi-deep lake and shallow lake were recognized from the drilling core of the second and third member of the Qingshankou Formation. 10 sedimentary microfacies are present, including dolomite, marl, limestone, oil shale, semi-deep lake turbidite, volcanic ash, seismite, semi-deep lake mudstone, shallow lake mudstone, and shallow lake turbidite microfacies. The second and third member of the Qingshankou Formation represents 422 meter-scale cycles (sixth-order cycle), 130 fifth-order cycles, 21 fourth-order cycles, and one third-order cycles. The special lithologies, such as mudstone, seismite, dolomite, volcanic ash, and so on are important to researches on source rocks and lacustrine event sediments.

Key Words: the second and third member of the Qingshankou Formation; sedimentary facies; sedimentary sequence; cyclic stratigraphy; CCSD-SK- south borehole; Cretaceous Coniacian; Songliao Basin

1 Introduction

In 1958, Songliao Petroleum Survey Group was the first to put forward the term “Qingshankou Layer” in the work on the “Viewpoint on the Stratigraphic Subdivision of the Songliao Plain”[1]. The primary section of the formation is located on the south bank of the Songhua River, Qingshankou Village, Nong’an County, Jilin Province. In 1959, Songliao Petroleum Survey Group and Songliao Petroleum Exploration Bureau

renamed the “Qingshankou Layer” as “Qingshankou Formation”. Well Hei-2 is an exploratory well for establishing the members of the Qingshankou Formation with a discovered thickness of Qingshankou Formation strata of 614 m. On the basis of the sedimentary characteristics of Well Hei-2, the Qingshankou Formation can be divided into three members. The lithology of the first member of the Qingshankou Formation is mainly composed of dark mudstone, one of the main hydrocarbon source beds of the Songliao Basin. The

WANG Pujun et al. / Earth Science Frontiers, 2009, 16(2): 288–313

second member and the third member of the Qingshankou Formation are mud—sand sediment transition zones. They are often collectively known as second and third members of the Qingshankou Formation because of their unclear boundary.

The second and third members of the Qingshankou Formation are widely distributed in the basin. The thickness is between 255–550 m in general. However, the thickness is much thinner in the Keshan-Lindian and Jiangqiao-Baicheng areas. It is 100–400 m and 53–124 m, respectively. The most important lithology of the members is gray, dark gray, and greenish-gray mudstone, and besides this, there is still a small amount of purple-red mudstone, gray muddy siltstone, grayish white sandstone, and calcareous siltstone[2].

The major contacts between the second and third member of the Qingshankou Formation and the underlying first member of the Qingshankou Formation and overlying Yaojia Formation are conformable, but with parallel disconformity in local sites.

Currently, it is generally believed that Qingshankou Formation belongs to upper Cretaceous according to the researches on paleontology[3–7], magneto-stratigraphy[8], isotope stratigraphy[9,10], and cyclic stratigraphy[11]. Through the comparison between the isotopic age values ((88.0 ± 0.3) Ma) for the bottom volcanic rocks of the second and third members of the Qingshankou Formation and the International Stratigraphic Chart (2004) , in combination with the top and biostratigraphic research on lower layer of the Qingshankou Formation[12–13], the article argues that the deposition period during the second and third member of the Qingshankou Formation corresponds approximately to the Coniacian,

Wang P J, Gao Y F, Ren Y G, et al. 40Ar/39Ar age and geochemical features of mugearite from the Qingshankou Formation: Significances for basin formation, hydrocarbon generation and petroleum accumulation of the Songliao Basin in Cretaceous. Acta Petrologica Sinica, 2009, in press.

International Commission on Stratigraphy. 2004 International Stratigrahpic Chart, 2004.

Table 1 Detailed description on the second and third members of the Qingshankou Formation (Depth: 1285.91-1701.52 m; Thickness: 415.61 m)

Recovery run-stratic order Interval (m) Thickness (m) Description of the cores

Overlying Formation: the first member of Yaojia Formation, parallel disconformity

43-14 1285.91–1286.26 0.35 Dark greenish gray silty mudstone, and massive bedding, with small amount of calcareous siltstone lumps.

43-15 1286.26–1287.07 0.81 Grayish brown mudstone, massive bedding, dark gray spots in the upper and basal parts of the section.

43-16 1287.07–1287.87 0.80 Dark greenish gray mudstone intercalated with light gray siltstone, with interrupted horizontal bedding and light gray siltstone stripes.

43-17 1287.87–1288.16 0.29 Dark gray mudstone intercalated with light gray siltstone, horizontal laminae, lenticular bedding in local sites, disturbed bedding, with siltstone, sand balls, and sandy lumps .

43-18 1288.16–1288.34 0.18 Dark greenish silty mudstone, interrupted wavy bedding, deformation bedding, massive bedding in the lower parts; light gray calcareous siltstone lens and lumps, few ostracoda fossil.

43-19 1288.34–1290.20 1.86 Grayish brown mudstone, massive bedding, greenish gray spot in local site. 43-20 1290.20–1290.34 0.14 Gray silty mudstone, massive bedding. 43-21 1290.34–1291.39 1.05 Grayish brown mudstone, massive bedding. 43-22 1291.39–1291.77 0.38 Dark greenish gray silty mudstone, massive bedding.

covering a geological age of approximately 4 Ma. The second and third members of the Qingshankou Formation recovered by CCSD-SK- s borehole is 415.61 m long with 100% of cores recovery[14], so the average deposition rate without compaction correction is approximately 10.39 cm/ka. If the minimal stratification described is less than 103.9 cm, the time scale will be millennium.

2 Detailed description on lithologic sequence

The detailed description on the core of the second and third members of the Qingshankou Formation is embodied in following two aspects. One is the description in millennium scale. The general minimal delamination thickness is 5 cm, and thus, a layer will be an interlayer if the thickness is less than 5 cm. However, the minimal delamination thickness of some specific lithology (such as argillaceous limestone, dolomite and ostracoda limestone) is 2 cm, and thus, a layer will be an interlayer if its thickness is less than 2 cm. The other is the description about some minor changes of environment within sedimentary microfacies, such as the changes in structure, composition, and colors.

Table 1 shows the detailed description of the second and third members of the Qingshankou Formation.

Figure 1 shows the columnar section of the second and third member of the Qingshankou Formation (CCSD-SK- s).

3 Lithology, lithofacies, and cyclic stratigraphy

The second and third member of the Qingshankou Formation contains the following 12 types of rocks: mudstone, ostracoda-bearing mudstone, silty mudstone, muddy siltstone, calcareous siltstone, oil shale, dolomite, marl, calcareous mudstone, crystalline limestone, ostracoda calstic limestone and volcanic ash. Mudstone and ostracoda-bearing mudstone are in the majority with large thickness and high occurrence frequency. Other rocks are


Continued

43-23 1291.77–1292.63 0.86 Grayish brown mudstone, massive bedding. 44-1 1292.63–1292.74 0.11 Grayish brown mudstone, massive bedding, dark greenish gray muddy siltstone lumps with

deformation bedding. 44-2 1292.74–1292.86 0.12 Dark greenish gray mudstone intercalated with very light gray calcareous siltstone, lenticular

bedding, and deformation bedding in the mudstone; ripple lamination in siltstone, calcareous siltstone stripes, and lumps with few ostracoda fossil.

44-3 1292.86–1293.00 0.14 Dark brown mudstone, massive bedding, dark greenish gray mudstone lumps, ostracoda fossils and calcareous concretions.

44-4 1293.00–1293.33 0.33 Brownish gray calcite-bearing silty mudstone, massive bedding, few ostracoda fossil and calcareous concretion.

44-5 1293.33–1294.94 1.61 Grayish brown mudstone, massive bedding, few ostracoda fossil and calcareous concretion. 44-6 1294.94–1295.18 0.24 Dark greenish gray mudstone, horizontal bedding, light gray siltstone stripes. 44-7 1295.18–1295.42 0.24 Brownish gray mudstone, horizontal bedding, with a thin bedded very light gray ostracoda

limestone lamella. 44-8 1295.42–1295.85 0.43 Grayish brown and greenish gray mudstone, massive bedding. 44-9 1295.85–1297.01 1.16 Grayish brown mudstone, massive bedding, few ostracoda fossil, and ostracoda clast

limestone lamella. 44-10 1297.01–1298.00 0.99 Brownish gray mudstone, massive bedding, few ostracoda fossil, and ostracoda clast

limestone lamella. 44-11 1298.00–1298.63 0.63 Brownish gray and dark greenish gray mudstone, massive bedding, few ostracoda fossil. 44-12 1298.63–1299.11 0.48 Dark greenish gray mudstone, massive bedding, grayish black mud gravels, few ostracoda

clast limestone lamella. 44-13 1299.11–1301.25 2.14 Dark greenish gray mudstone, massive bedding, few ostracoda fossil. 44-14 1301.25–1303.72 2.47 Medium dark gray mudstone, horizontal bedding, ostracoda fossils, ostracoda clast limestone

lamellae in local site. 44-15 1303.72–1303.82 0.10 Medium dark gray ostracoda-bearing mudstone, horizontal bedding, ostracoda fossils. 44-16 1303.82–1304.50 0.68 Dark gray mudstone intercalated with medium light gray ostracoda clast limestone, horizontal

bedding, ripple lamination, ostracoda fossils, and ostracoda clast limestone stripes. 45-1 1304.50–1306.85 2.35 Dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes, and complete

ostracoda fossils. 45-2 1306.85–1307.21 0.36 Dark gray ostracoda-bearing mudstone, horizontal bedding, with intercalated ostracoda clast

limestone lamellae. 45-3 1307.21–1307.50 0.29 Dark gray mudstone, horizontal bedding, ostracoda clast limestone lamellae, and complete

ostracoda fossils. 45-4 1307.50–1307.80 0.30 Dark gray ostracoda-bearing mudstone, horizontal bedding, ostracoda clast limestone stripes. 45-5 1307.80–1308.10 0.30 Dark gray mudstone, horizontal bedding, ostracoda fossils, and ostracoda clast limestone

stripes. 45-6 1308.10–1308.80 0.70 Dark gray ostracoda-bearing mudstone intercalated with ostracoda clast limestone, horizontal

bedding, lenticular bedding in local site, with normal graded bedding, ostracoda fossils, and ostracoda clast limestone stripes.

45-7 1308.80–1309.33 0.53 Medium dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding, lenticular bedding; ostracoda clast limestone in the lower section, horizontal bedding, ostracoda fossils, and ostracoda clast limestone stripes.

45-8 1309.33–1310.00 0.67 Dark gray mudstone intercalated with ostracoda limestone, horizontal bedding, ripple lamination.

46-1 1310.00–1310.18 0.18 Dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes, and lamellae. 46-2 1310.18–1310.96 0.78 Gray mudstone, horizontal bedding, ostracoda fossils, and ostracoda clast limestone stripes. 46-3 1310.96–1312.00 1.04 Dark gray mudstone intercalated with ostracoda clast limestone, ripple lamination, ostracoda

clast limestone stripes. 46-4 1312.00–1312.07 0.07 Light gray ostracoda limestone. 46-5 1312.07–1315.00 2.93 Dark gray mudstone intercalated with ostracoda clast limestone, ripple lamination, ostracoda fossils.

47-1 1315.00–1315.22 0.22 Dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes. 47-2 1315.22–1315.68 0.46 Medium gray mudstone, horizontal bedding; ostracoda clast limestone lamellae. 47-3 1315.68–1316.41 0.73 Medium dark gray mudstone, horizontal bedding, some ostracoda fossils, with smaller

individual size. 47-4 1316.41–1316.53 0.12 Medium dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding,

ripple lamination, some ostracoda clast limestone stripes, and ostracoda fossils. 47-5 1316.53–1316.82 0.29 Medium dark gray mudstone, horizontal bedding, with some ostracoda fossil clasts and relic

plant fragments. 47-6 1316.82–1316.94 0.12 Medium dark gray mudstone interbedded with ostracoda clast limestone, horizontal bedding,

ripple lamination. 47-7 1316.94–1317.38 0.44 Medium gray ostracoda-bearing mudstone, horizontal bedding, with limy mudstone lamellae

in the basal part of the section. 47-8 1317.38–1318.40 1.02 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone lamellae and

complete ostracoda fossils.


Continued

47-9 1318.40–1319.40 1.00 Dark gray ostracoda-bearing mudstone, horizontal bedding, with thin bedded ostracoda clast limestone lamellae some ostracoda, and conchonstracan fossils with relic plant fragments.

47-10 1319.40–1320.22 0.82 Grayish black mudstone intercalated with ostracoda clast limestone, horizontal bedding, ripple lamination, ostracoda clast limestone lamellae and stripes, with ostracoda and silicified fossils.

47-11 1320.22–1322.25 2.03 Dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding, ripple lamination, conchonstracan and ostracoda fossils, ostracoda clast limestone stripes and lamellae.

47-12 1322.25–1322.62 0.37 Medium dark gray ostracoda-bearing mudstone, horizontal bedding, some ostracoda fossils and ostracoda clast limestone lamellae.

47-13 1322.62–1322.95 0.33 Medium dark gray mudstone, horizontal bedding, ostracoda fossils. 47-14 1322.95–1323.29 0.34 Medium dark gray mudstone interbedded with ostracoda clast limestone, horizontal bedding,

ripple lamination, ostracoda clast limestone stripes, and lenses. 47-15 1323.39–1324.88 1.49 Medium dark gray mudstone, horizontal bedding, some ostracoda and conchonstracan fossils,

ostracoda clast limestone stripes and lamellae. 47-16 1324.88–1325.00 0.12 Medium dark gray mudstone interbedded with ostracoda clast limestone, ripple lamination,

ostracoda fossils. 47-17 1325.00–1325.20 0.20 Medium dark gray ostracoda-bearing mudstone intercalated with ostracoda clast limestone,

horizontal bedding, ripple lamination, ostracoda fossils, fossil fragments on top of the erosion surface.

47-18 1325.20–1326.92 1.72 Medium gray mudstone intercalated with ostracoda clast limestone, horizontal bedding, ripple lamination, ostracoda fossils, and an 8mm thick tuff-like bed occurred in 1325.31m.

47-19 1326.92–1327.02 0.10 Medium gray mudstone interbedded with ostracoda clast limestone, horizontal bedding, ripple lamination, ostracoda fossils, and fossil fragments.

48-1 1327.02–1327.25 0.23 Medium dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding, ostracoda fossils.

48-2 1327.25–1327.62 0.37 Medium dark gray mudstone, horizontal bedding, some ostracoda fossils. 48-3 1327.62–1328.12 0.50 Medium gray ostracoda-bearing mudstone, horizontal bedding, ostracoda fossils, few

conchonstracan fossil. 48-4 1328.12–1328.29 0.17 Medium light gray mudstone, horizontal bedding, ostracoda clast limestone lamellae, few

conchonstracan fossil. 48-5 1328.29–1328.99 0.70 Medium dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding,

ripple lamination, ostracoda fossils. 48-6 1328.99–1329.09 0.10 Medium gray mudstone, horizontal bedding, ostracoda clast limestone lamella in the basal

part of the lower section with ostracoda fossils. 48-7 1329.09–1330.78 1.69 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone in the basal part

of the section. 48-8 1330.78–1331.52 0.74 Medium gray ostracoda-bearing mudstone, horizontal bedding, with ostracoda fossils, few

ostracoda clast limestone lamella. 48-9 1331.52–1331.87 0.35 Medium dark gray mudstone, horizontal bedding, ostracoda fossils, ostracoda clast limestone

stripes and lamellae in the basal part of the section with erosion surface. 48-10 1331.87–1332.42 0.55 Medium dark gray ostracoda-bearing mudstone, horizontal bedding, some ostracoda and few

conchonstracan fossils. 48-11 1332.42–1332.84 0.42 Medium dark gray mudstone, horizontal bedding, some ostracoda and conchonstracan fossils,

ostracoda clast limestone stripes and lamellae. 48-12 1332.84–1334.45 1.61 Medium dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding,

ripple lamination, some ostracoda and conchonstracan fossils, ostracoda clast limestone stripes and lamellae.

48-13 1334.45–1335.40 0.95 Medium dark gray mudstone, horizontal bedding, ostracoda fossils and ostracoda clast limestone stripes.

48-14 1335.40–1336.57 1.17 Medium dark gray mudstone, horizontal bedding, ostracoda fossils and ostracoda clast limestone stripes and lamellae.

48-15 1336.57–1337.12 0.55 Medium dark gray ostracoda-bearing mudstone, horizontal bedding, ostracoda fossils. 48-16 1337.12–1338.02 0.90 Medium dark gray mudstone, horizontal bedding, ostracoda fossils and ostracoda clast

limestone stripes and lamellae. 48-17 1338.02–1339.03 1.01 Medium gray ostracoda-bearing mudstone intercalated with ostracoda clast limestone,

horizontal bedding, ripple lamination, ostracoda fossils, and ostracoda clast limestone stripes. 49-1 1339.03–1342.01 2.98 Medium dark gray mudstone interbedded with ostracoda clast limestone, horizontal bedding,

ripple lamination, disturbed bedding, with ostracoda fossils and ostracoda clast limestone stripes and lumps.

49-2 1342.01–1342.06 0.05 Light gray ostracoda clast limestone, ripple lamination, with mudstone stripes in the upper part of the section.

49-3 1342.06–1347.80 5.74 Medium dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding, ripple lamination, disturbed bedding, ostracoda fossils, intercalated with three layers of dark greenish gray mudstone.

49-4 1347.80–1347.95 0.15 Medium dark gray mudstone, horizontal bedding, ostracoda fossils.


Continued

49-5 1347.95–1348.52 0.57 Medium dark gray mudstone interbedded with light gray ostracoda clast limestone, ripple lamination, horizontal bedding, some ostracoda fossils and ostracoda clast limestone lamellae.

49-6 1348.52–1348.66 0.14 Medium dark gray mudstone, horizontal bedding, with very few ostracoda fossil. 49-7 1348.66–1349.20 0.54 Medium dark gray mudstone, horizontal bedding, ostracoda fossils with different size. 49-8 1349.20–1349.44 0.24 Medium dark gray mudstone, horizontal bedding, some ostracoda clast limestone stripes and

lamellae. 49-9 1349.44–1350.30 0.86 Medium dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding,

ripple lamination, some ostracoda fossils and ostracoda clast limestone stripes and lamellae. 49-10 1350.3–1351.05 0.75 Medium gray mudstone, horizontal bedding, ripple lamination, some ostracoda fossils. 49-11 1351.05–1351.69 0.64 Medium dark gray mudstone intercalated with laminated ostracoda clast limestone, horizontal

bedding, ripple lamination, some ostracoda and conchonstracan fossils with ostracoda clast limestone stripes.

49-12 1351.69–1352.38 0.69 Medium dark gray ostracoda-bearing mudstone, horizontal bedding, some ostracoda and conchonstracan fossils.

49-13 1352.38–1353.43 1.05 Medium gray mudstone intercalated with laminated ostracoda clast limestone, horizontal bedding, ripple lamination, with slightly scouring surface at the bottom of the ostracoda clast limestone, some ostracoda and conchonstracan fossils with ostracoda clast limestone stripes.

49-14 1353.43–1353.91 0.48 Medium dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding, ripple lamination, some conchonstracan and ostracoda fossils.

49-15 1353.91–1354.54 0.63 Medium dark gray mudstone, horizontal bedding, some ostracoda and conchonstracan fossils. 49-16 1354.54–1354.96 0.42 Medium dark gray mudstone intercalated with laminated ostracoda clast limestone, horizontal

bedding, ripple lamination, few conchonstracan and ostracoda fossil, ostracoda clast limestone stripes.

49-17 1354.96–1355.23 0.27 Medium dark gray mudstone, horizontal bedding, ostracoda fossils. 50-1 1355.23–1355.65 0.42 Medium dark gray mudstone, horizontal bedding, ostracoda fossils, ostracoda clast limestone

lamellae in the basal part of the section. 50-2 1355.65–1356.77 1.12 Dark greenish gray mudstone, with unclear horizontal ripple lamination, more ostracoda

fossils and pyrite-riched layers. 50-3 1356.77–1358.65 1.88 Medium dark gray mudstone intercalated with laminated light gray ostracoda clast limestone,

ripple lamination. 50-4 1358.65–1358.80 0.15 Medium gray ostracoda clast limestone thinly interbedded with mudstone, ripple lamination,

ostracoda fossils. 50-5 1358.80–1359.35 0.55 Medium gray ostracoda-bearing mudstone thinly interbedded with ostracoda clast limestone,

ripple lamination, ostracoda fossil, ostracoda clast limestone stripes. 50-6 1359.35–1359.88 0.53 Dark gray mudstone thinly interbedded with ostracoda clast limestone, ripple lamination,

horizontal bedding, ostracoda fossils and ostracoda clast limestone stripes, few conchonstracan fossil.

50-7 1359.88–1360.40 0.52 Medium gray ostracoda clast limestone thinly interbedded with mudstone, ripple lamination, horizontal bedding, ostracoda fossils and ostracoda clast limestone stripes.

50-8 1360.40–1360.49 0.09 Dark greenish gray mudstone thinly interbedded with olive gray ostracoda clast limestone, ripple lamination, horizontal bedding, ostracoda fossils, and ostracoda clast limestone stripes.

50-9 1360.49–1360.86 0.37 Medium dark gray mudstone intercalated with laminated ostracoda clast limestone, ripple lamination, horizontal bedding, conchonstracan and ostracoda fossils, ostracoda clast limestone stripes.

50-10 1360.86–1361.12 0.26 Medium gray mudstone intercalated with laminated ostracoda clast limestone, ripple lamination, horizontal bedding, conchonstracan and ostracoda fossils, ostracoda clast limestone stripes.

50-11 1361.12–1361.75 0.63 Olive gray mudstone intercalated with laminated ostracoda clast limestone, ripple lamination, horizontal bedding, ostracoda fossils and ostracoda clast limestone stripes.

50-12 1361.75–1361.83 0.08 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil. 51-1 1361.84–1362.46 0.62 Medium dark gray mudstone, horizontal ripple lamination, horizontal bedding, few ostracoda

fossil. 51-2 1362.46–1362.51 0.05 Dark greenish gray mudstone, massive bedding, poorly layered. 51-3 1362.51–1364.14 1.63 Medium dark gray mudstone intercalated with laminated ostracoda clast limestone, ripple

lamination, ostracoda fossils. 51-4 1364.14–1364.34 0.20 Medium dark gray mudstone thinly interbedded with ostracoda calstic limestone, horizontal

ripple lamination, horizontal bedding, ostracoda fossils, ostracoda clast limestone stripes. 51-5 1364.34–1366.34 2.00 Medium gray mudstone, horizontal bedding, ostracoda fossils, ostracoda clast limestone

stripes. 51-6 1366.34–1368.47 2.13 Medium gray mudstone thinly interbedded with ostracoda clast limestone, horizontal ripple

lamination, horizontal bedding, deformation bedding, load structure, some ostracoda and conchonstracan fossils, ostracoda clast limestone stripes.

51-7 1368.47–1369.10 0.63 Light greenish gray mudstone, massive bedding, ostracoda fossil fragments. 51-8 1369.10–1370.06 0.96 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes. 51-9 1370.06–1370.64 0.58 Medium gray mudstone interbedded with ostracoda clast limestone, horizontal bedding and

ripple lamination.


Continued

51-10 1370.64–1371.41 0.77 Medium gray mudstone, massive bedding, more ostracoda fossils locally enriched. 51-11 1371.41–1373.06 1.65 Medium gray mudstone intercalated with ostracoda clast limestone, horizontal bedding and

ripple lamination. 51-12 1373.06–1373.77 0.71 Dark gray mudstone intercalated with laminated ostracoda clast limestone, horizontal

bedding, ripple lamination, ostracoda fossils and ostracoda clast limestone stripes, with dark greenish gray spots in the upper part.

52-1 1373.77–1373.91 0.14 Dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding, and ripple lamination.

52-2 1373.91–1374.10 0.19 Dark greenish gray mudstone, with unclear horizontal massive bedding, some ostracoda clast limestone lamellae and pyrite grains.

52-3 1374.10–1374.17 0.07 Dark gray mudstone, horizontal bedding, ostracoda fossil fragments. 52-4 1374.17–1374.80 0.63 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes, with dark

greenish gray spots in its basal part. 52-5 1374.80–1375.02 0.22 Medium gray mudstone, horizontal bedding, with light greenish gray spots, a dark greenish

gray ostracoda-bearing mudstone lamella in the upper part, thickness less than 1 cm. 52-6 1375.02–1375.53 0.51 Grayish black ostracoda-bearing mustone, horizontal bedding with ostracoda fossil fragments.52-7 1375.53–1377.03 1.50 Medium gray mudstone, horizontal bedding some ostracoda and conchonstracan fossils,

ostracoda clast limestone lamellae. 52-8 1377.03–1377.62 0.59 Medium dark gray mudstone, horizontal bedding and ripple lamination, laminated ostracoda

clast limestone lamellae, with complete ostracoda fossil and several conchonstracan fossil-riched beds.

52-9 1377.62–1377.98 0.36 Medium gray mudstone, horizontal bedding, ostracoda clast limestone stripes with horizontal ripple lamination.

52-10 1377.98–1379.27 1.29 Medium dark gray ostracoda-bearing mudstone, horizontal bedding, ripple lamination, with more ostracoda fossil fragments, few ostracoda clast limestone lamellae.

52-11 1379.27–1379.99 0.72 Medium gray mudstone, massive bedding, more fossil fragments. 52-12 1379.99–1380.64 0.65 Dark gray mudstone, horizontal bedding, some ostracoda clast limestone stripes and lamellae.52-13 1380.64–1382.32 1.68 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes and

lamellae, conchonstracan and plant fossils and fossil fragments with vertical fractures. 52-14 1382.32–1382.99 0.67 Medium gray mudstone, horizontal bedding, fossil fragments and conchonstracan fossils,

ostracoda clast limestone lamellae. 52-15 1382.99–1383.01 0.02 Medium dark gray ostracoda clast limestone, horizontal ripple lamination, ostracoda clasti

limestone lamellae. 52-16 1383.01–1383.46 0.45 Dark gray mudstone, horizontal bedding, few fossil fragments. 52-17 1383.46–1383.89 0.43 Medium dark gray mudstone, horizontal bedding, a vertical fracture filled with ostracoda

fossil fragments. 52-18 1383.89–1384.00 0.11 Medium gray mudstone, massive bedding, few ostracoda fossil fragments but more

conchonstracan fossils. 52-19 1384.00–1384.58 0.58 Dark gray mudstone intercalated with laminated medium. light gray ostracoda clast limestone,

horizontal bedding, ripple lamination, more fossil fragments, conchonstracan fossils and ostracoda clast limestone stripes.

52-20 1384.58–1384.70 0.12 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil fragments. 52-21 1384.70–1385.27 0.57 Medium gray mudstone, horizontal bedding, thin layers of dark greenish gray mudstone

lamellae in the upper section, poorly layered. 52-22 1385.27-1385.47 0.20 Light olive gray limy mudstone thinly interbedded with dark gray mudstone, horizontal

bedding, ripple lamination, deformation bedding, load structure, ostracoda and conchonstracan fossils in the mudstone.

52-23 1385.47–1385.84 0.37 Medium dark gray ostracoda-bearing limy mudstone interbedded with dark gray mudstone, horizontal bedding, with more fossil fragments and conchonstracan fossils in the mudstone.

52-24 1385.84–1386.14 0.30 Medium gray mudstone, horizontal bedding, some ostracoda fossil fragments and conchonstracan fossils.

53-1 1386.14–1386.96 0.82 Medium gray mudstone, horizontal bedding, dark greenish gray mudstone in the upper part , some ostracoda clast limestone stripes and lamellae, with scouring surface at the bottom.

53-2 1386.96–1388.68 1.72 Medium dark gray mudstone intercalated with laminated ostracoda clast limestone, horizontal bedding, ripple lamination, ostracoda clast limestone stripes, more fossil fragments and conchonstracan fossils.

53-3 1388.68–1391.32 2.64 Greenish gray mudstone, massive bedding, ostracoda clast limestone lamellae in local sites. 53-4 1391.32–1391.51 0.19 Medium dark gray mudstone, massive bedding, ostracoda clast limestone lamella in the upper

part of the section. 53-5 1391.51–1391.98 0.47 Medium gray mudstone, massive bedding. 53-6 1391.98–1392.24 0.26 Greenish gray mudstone, massive bedding, medium gray spots in local sites. 53-7 1392.24–1393.81 1.57 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes and

lamellae. 53-8 1393.81–1395.02 1.21 Medium gray mudstone, massive bedding, with conchonstracan fossils enriched in local site

with small amount of ostracoda fragments and fossils.


Continued

53-9 1395.02–1396.97 1.95 Medium dark gray mudstone intercalated with ostracoda calstic limestone, horizontal bedding, ripple lamination, ostracoda clast limestone stripes, ostracoda and conchonstracan fossils.

53-10 1396.97–1398.16 1.19 Greenish gray mudstone, massive bedding, some fossil fragments. 54-1 1398.16–1398.28 0.12 Greenish gray mudstone, horizontal bedding but locally unclear, ostracoda clast limestone

lamellae in the basal part. 54-2 1398.28–1399.13 0.85 Medium gray mudstone, massive bedding, few ostracoda fossil fragments and green spots. 54-3 1399.13–1399.25 0.12 Medium dark gray mudstone, horizontal bedding, few ostracoda clasts. 54-4 1399.25–1399.82 0.57 Dark gray mudstone, horizontal bedding unclear, some ostracoda clast limestone stripes,

fossil fragments in the basal parts in the lower section. 54-5 1399.82–1400.13 0.31 Medium dark gray mudstone, horizontal bedding, some ostracoda and conchonstracan fossils,

ostracoda clast limestone stripes. 54-6 1400.13–1400.42 0.29 Medium gray mudstone, horizontal bedding, ostracoda clast limestone lamellae. 54-7 1400.42–1401.01 0.59 Medium dark gray mudstone intercalated with medium. light gray ostracoda clast limestone,

horizontal bedding, ripple lamination, disturbed bedding, ostracoda clast limestone stripes. 54-8 1401.01–1403.17 2.16 Greenish gray mudstone, massive bedding, some irregular fractures in the upper part filled

with calcite, ostracoda fossils and more fossil fragments in the lower parts section and ostracoda clast limestone laminae.

54-9 1403.17–1403.94 0.77 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes, with small amount of fossil fragments.

54-10 1403.94–1404.11 0.17 Medium dark gray mudstone interbedded with ostracoda clast limestone, horizontal bedding, ripple lamination.

54-11 1404.11–1404.78 0.67 Dark gray mudstone, horizontal ripple lamination, ostracoda clast limestone lamellae in the basal parts more fossil fragments and ostracoda clasts are concentrated in the upper parts of the section.

54-12 1404.78–1406.88 2.10 Greenish gray mudstone, massive bedding, fossil fragments in the basal part, ostracoda clast limestone stripes in the middle.

54-13 1406.88–1407.27 0.39 Light olive gray limy mudstone, massive bedding, greenish gray mudstone lamellae. 54-14 1407.27–1408.73 1.46 Greenish gray mudstone, massive bedding, ostracoda fossil fragments and ostracoda clast

limestone stripes in the basal part. 54-15 1408.73–1409.23 0.50 Medium dark gray mudstone, horizontal bedding, conchonstracan fossils with few fossil

fragments and ostracoda clast limestone stripes in the upper parts, greenish-gray mud gravels in the basal parts.

54-16 1409.23–1410.24 1.01 Greenish gray mudstone, massive bedding, ostracoda clast limestone lamellae and marl lumps. 54-17 1410.24–1410.42 0.18 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes with

horizontal ripple lamination. 55-1 1410.42–1410.71 0.29 Greenish gray mudstone, horizontal bedding, with medium gray spots, more ostracoda fossil

fragments at its basal section, few complete ostracoda fossil. 55-2 1410.71–1411.00 0.29 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes, few green

spots in its upper parts. 55-3 1411.00–1411.11 0.11 Light olive gray lime mudstone, massive bedding, a nearly horizontal fracture in the middle,

filled with calcite. 55-4 1411.11–1411.57 0.46 Medium dark gray mudstone interbedded with ostracoda clast limestone, horizontal bedding

and ripple lamination. 55-5 1411.57–1411.91 0.34 Medium light gray mudstone, horizontal bedding, more fossil fragments, ostracoda clast

limestone stripes in the basal parts. 55-6 1411.91–1413.42 1.51 Greenish gray mudstone, indistinct horizontal bedding, more ostracoda clast limestone stripes

and increasing downwards. 55-7 1413.42–1413.77 0.35 Medium gray mudstone, horizontal bedding, ostracoda clast limestone stripes. 55-8 1413.77–1413.97 0.20 Light olive gray limy mudstone, massive bedding. 55-9 1413.97–1414.51 0.54 Medium dark gray mudstone, horizontal bedding, more ostracoda clast limestone lamellae,

few conchonstracan fossils. 55-10 1414.51–1415.26 0.75 Medium gray mudstone intercalated with ostracoda clast limestone, ripple lamination,

horizontal bedding, conchonstracan fossils, more fossil fragments and ostracoda clast limestone lamellae in the upper and middle parts of the section.

55-11 1415.26–1415.53 0.27 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes with horizontal ripple lamination.

55-12 1415.53–1416.93 1.40 Medium gray mudstone, massive bedding, marl lumps in the upper section, some ostracoda clast limestone stripes and locally greenish gray spots, pyrite and ostracoda clast limestone lamellae in the lower section.

56-1 1416.93–1417.32 0.39 Medium dark gray mudstone, horizontal bedding, greenish gray mudstone lamella in the upper section, fossil fragments.

56-2 1417.32–1417.54 0.22 Medium gray mudstone intercalated with ostracoda clast limestone, horizontal bedding, some conchonstracan fossils.

56-3 1417.54–1417.83 0.29 Dark gray ostracoda-bearing mudstone, horizontal bedding, few fossil fragments.


Continued

56-4 1417.83–1418.42 0.59 Medium gray mudstone, horizontal bedding, ostracoda clast limestone stripes, more fossil fragments.

56-5 1418.42–1418.72 0.30 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes. 56-6 1418.72–1418.94 0.22 Greenish gray mudstone, massive bedding, ostracoda clast limestone lamella. 56-7 1418.94–1419.23 0.29 Dark greenish gray mudstone thinly interbedded with light olive gray ostracoda clast

limestone, horizontal bedding, ripple lamination, ostracoda clast limestone stripes. 56-8 1419.23–1420.07 0.84 Dark gray mudstone, horizontal bedding, locally ostracoda clast limestone stripes. 56-9 1420.07–1420.29 0.22 Medium dark gray mudstone intercalated with medium light gray ostracoda clast limestone,

horizontal bedding, with local ripple lamination. 56-10 1420.29–1420.60 0.31 Greenish gray and medium dark gray mudstone, horizontal bedding, ostracoda fragments and

ostracoda clast limestone stripes. 56-11 1420.60–1421.31 0.71 Medium dark gray mudstone, horizontal bedding, ripple lamination, locally ostracoda clast

limestone stripes. 56-12 1421.31–1421.44 0.13 Medium gray ostracoda-bearing mudstone, horizontal bedding, ripple lamination. 56-13 1421.44–1421.60 0.16 Medium dark gray mudstone, horizontal bedding. 56-14 1421.60–1421.75 0.15 Light olive gray lime mudstone, massive bedding. 56-15 1421.75–1423.24 1.49 Greenish gray mudstone, massive bedding, ostracoda fossil fragments in local site. 56-16 1423.24–1423.88 0.64 Medium gray mudstone, horizontal bedding, locally limy mudstone stripes and ostracoda clast

limestone stripes in the basal parts. 56-17 1423.88–1423.94 0.06 Light olive gray lime mudstone, massive bedding. 56-18 1423.94–1424.03 0.09 Greenish gray mudstone, massive bedding, ostracoda clast limestone lamellae with horizontal

ripple lamination in the lower parts. 56-19 1424.03–1424.83 0.80 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes with

horizontal ripple lamination. 56-20 1424.83–1425.00 0.17 Medium gray mudstone, massive bedding, ostracoda clast limestone stripes in the basal

section. 56-21 1425.00–1425.11 0.11 Light olive gray lime mudstone; with greenish gray mudstone lamella 1cm thick in the upper

section, massive bedding. 56-22 1425.11–1427.30 2.19 Greenish gray mudstone, massive bedding, ostracoda clast limestone lamellae in the lower

section. 56-23 1427.30–1428.39 1.09 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes and fossil

fragments in local bedding planes. 56-24 1428.39–1429.05 0.66 Greenish gray mudstone, massive bedding. 57-1 1429.05–1430.25 1.20 Greenish gray mudstone, massive bedding, fossil fragments, locally ostracoda clast limestone

lamellae. 57-2 1430.25–1432.06 1.81 Dark greenish gray mudstone, massive bedding, fossil fragments, locally ostracoda clast

limestone lamellae. 57-3 1432.06–1432.49 0.43 Greenish gray mudstone, massive bedding or indistinct horizontal bedding, some fossil

fragments with plant fossils. 57-4 1432.49–1432.71 0.22 Dark greenish gray mudstone, horizontal bedding, some ostracoda clast limestone stripes with

horizontal ripple lamination. 57-5 1432.71–1432.87 0.16 Medium dark gray mudstone thinly interbedded with light gray ostracoda clast limestone,

horizontal bedding, ripple lamination. 57-6 1432.87–1433.84 0.97 Dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes and plant fossil

fragments. 57-7 1433.84–1435.93 2.09 Greenish gray mudstone, massive bedding, some local irregular fractures, filled with calcite;

strawberry-shaped pyrites and few ostracoda clast limestone strip and lamella in the lower section.

57-8 1435.93–1437.94 2.01 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes, locally conchonstracan fossils.

57-9 1437.94–1438.32 0.38 Dark gray mudstone, horizontal bedding, ostracoda fossil fragments. 57-10 1438.32–1438.80 0.48 Dark gray mudstone interbedded with light gray ostracoda clast limestone, horizontal

bedding, ripple lamination, ostracoda clast limestone stripes, more ostracoda fossils in the middle and lower section.

57-11 1438.80–1440.32 1.52 Medium dark gray mudstone intercalated with ostracoda calstic limestone, horizontal bedding, ripple lamination, ostracoda clast limestone stripes, few conchonstracan fossil, locally abundant ostracoda fossil fragments.

57-12 1440.32–1440.41 0.09 Light olive gray marlite, massive bedding. 57-13 1440.41–1440.79 0.38 Medium dark gray mudstone, horizontal bedding, ostracoda calstic limestone stripes, more

fossil fragments in the lower section. 57-14 1440.79–1440.86 0.07 Light olive gray limy mudstone, massive bedding. 57-15 1440.86–1441.32 0.46 Greenish gray mudstone, horizontal bedding, some ostracoda fossil fragments. 57-16 1441.32–1441.41 0.09 Medium gray mudstone, horizontal bedding, ostracoda clast limestone stripes in the basal

parts. 58-1 1441.41–1441.64 0.23 Dark greenish gray mudstone, horizontal bedding, fossil fragments.


Continued

58-2 1441.64–1441.85 0.21 Greenish gray mudstone, horizontal bedding, few ostracoda fossil fragment. 58-3 1441.85–1442.40 0.55 Dark greenish gray mudstone, horizontal bedding, ostracoda clast limestone stripes with

horizontal ripple lamination. 58-4 1442.40–1443.28 0.88 Dark gray mudstone intercalated with laminated ostracoda clast limestone, horizontal

bedding, ripple lamination. 58-5 1443.28–1443.79 0.51 Medium gray mudstone, horizontal bedding, ostracoda clast limestone stripes with horizontal

ripple lamination. 58-6 1443.79–1444.02 0.23 Medium dark gray mudstone thinly interbedded with ostracoda clast limestone, horizontal

bedding, ripple lamination. 58-7 1444.02–1444.35 0.33 Medium gray mudstone, horizontal bedding, ostracoda clast limestone stripes. 58-8 1444.35–1444.64 0.29 Medium dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding,

ripple lamination; a bluish (5B5/1) gray mudstone bed, less than 1 cm, on top of the section, some conchonstracan fossils and ostracoda clast limestone stripes.

58-9 1444.64–1444.96 0.32 Medium dark gray mudstone, horizontal bedding, few ostracoda clast limestone stripes. 58-10 1444.96–1445.42 0.46 Dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding, ripple

lamination. 58-11 1445.42–1445.68 0.26 Medium gray mudstone, horizontal bedding, ostracoda clast limestone lamellae in the lower

section. 58-12 1445.68–1446.02 0.34 Greenish gray mudstone, horizontal bedding, ostracoda clast limestone stripes. 58-13 1446.02–1446.37 0.35 Medium dark gray mudstone, massive bedding, ostracoda fossil fragments. 58-14 1446.37–1446.50 0.13 Light olive gray lime mudstone, massive bedding. 58-15 1446.50–1446.66 0.16 Greenish gray mudstone, massive bedding, ostracoda fossil fragments. 58-16 1446.66–1448.17 1.51 Medium dark gray mudstone, horizontal bedding, few ostracoda clast limestone stripes and

lamellae. 58-17 1448.17–1448.40 0.23 Olive gray mudstone, horizontal bedding, some ostracoda fossil fragments. 58-18 1448.40–1448.55 0.15 Medium dark gray mudstone, horizontal bedding, some ostracoda clast limestone stripes. 58-19 1448.55–1448.75 0.20 Greenish gray mudstone, massive bedding, ostracoda fossil fragments, some irregular

fractures in the upper section, filled with dark gray mudstone. 58-20 1448.75–1449.07 0.32 Dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding, ripple

lamination. 58-21 1449.07–1449.27 0.20 Greenish gray mudstone, horizontal bedding. 58-22 1449.27–1449.39 0.12 Light olive gray limy mudstone, massive bedding. 58-23 1449.39–1449.52 0.13 Medium dark gray mudstone, horizontal bedding, few ostracoda calstic limestone lumps,

calcite veins and ostracoda-bearing mudstone in the lower section. 58-24 1449.52–1449.68 0.16 Light olive gray lime mudstone, massive bedding. 58-25 1449.68–1450.91 1.23 Medium dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding,

ripple lamination. 58-26 1450.91–1451.27 0.36 Greenish gray mudstone, horizontal bedding, ostracoda fossil fragments. 58-27 1451.27–1451.68 0.41 Medium dark gray mudstone, horizontal bedding, conchonstracan fossils, ostracoda clast

limestone stripes. 58-28 1451.68–1452.14 0.46 Dark gray mudstone, horizontal bedding, conchonstracan fossils, ostracoda clast limestone

stripe with horizontal ripple laminations. 58-29 1452.14–1452.67 0.53 Olive gray mudstone, horizontal bedding, local ostracoda clast limestone lamellae. 58-30 1452.67–1452.99 0.32 Dark greenish gray mudstone, indistinct horizontal bedding, locally ostracoda fossil

fragments. 58-31 1452.99–1453.29 0.30 Greenish gray mudstone, indistinct horizontal bedding, locally ostracoda fossil fragments. 58-32 1453.29–1453.69 0.40 Dark greenish gray mudstone, indistinct horizontal bedding, locally ostracoda fossil

fragments. 59-1 1453.69–1455.57 1.88 Dark greenish gray mudstone, massive bedding, locally indistinct horizontal bedding, some

ostracoda fossils, few bivalve fossil. 59-2 1455.57–1458.07 2.50 Dark gray mudstone, horizontal bedding, ostracoda fossils, few bivalve fossil, locally medium

gray ostracoda clast limestone and some escape trace ichnofossils (penetrating the fossil fragment beds).

59-3 1458.07–1459.62 1.55 Medium dark gray mudstone, horizontal bedding, ostracoda fossils, few bivalve fossil fragments, with greenish gray mudstone bed on the top, locally laminated medium gray ostracoda clast limestone.

59-4 1459.62–1460.24 0.62 Greenish gray mudstone, indistinct horizontal bedding, locally enriched ostracoda fossils, with local light greenish gray mudstone and ostracoda clast limestone stripes and lumps.

59-5 1460.24–1461.15 0.91 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone lamellae and stripes, with a lamella of ostracoda clast limestone and scouring surface at the bottom.

59-6 1461.15–1462.78 1.63 Olive gray mudstone, indistinct horizontal bedding, locally dark gray mudstone stripes and lumps; with ostracoda clast limestone lamellae and stripes in the lower part of section.

59-7 1462.78–1463.46 0.68 Dark gray mudstone, horizontal bedding, ostracoda clast limestone lamellae in local site and some ostracoda fossils.


Continued

59-8 1463.46–1464.49 1.03 Medium dark gray mudstone, indistinct horizontal bedding, ostracoda fossils. 60-1 1464.48–1464.66 0.18 Medium dark gray mudstone, indistinct horizontal bedding, ostracoda clast limestone stripes. 60-2 1464.66–1467.28 2.62 Medium dark gray mudstone thinly interbedded with dark gray ostracoda clast limestone,

horizontal bedding, ripple lamination, abundant dark gray , light olive gray ostracoda clast limestone lamellae and stripes with few conchonstracan fossil.

60-3 1467.28–1467.33 0.05 Light olive gray limy mudstone, massive bedding, few ostracoda clast limestone lumps. 60-4 1467.33–1469.08 1.75 Medium dark gray mudstone thinly interbedded with dark gray ostracoda clasitc limestone,

horizontal bedding, ripple lamination, more dark gray and light olive gray ostracoda clast limestone lamellae; few conchonatracan fossil.

60-5 1469.08–1470.38 1.30 Medium dark gray mudstone intercalated with dark gray ostracoda calstic limestone, horizontal bedding, ripple lamination.

60-6 1470.38–1471.24 0.86 Medium dark gray mudstone, horizontal bedding, few dark gray ostracoda clast limestone lamella and stripe.

61-1 1471.24–1471.47 0.23 Dark gray mudstone, horizontal bedding, few calcareous fossil fragment. 61-2 1471.47–1472.89 1.42 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil. 61-3 1472.89–1475.79 2.90 Dark gray mudstone, horizontal bedding, ostracoda and conchonstracan fossils and several

stripes of ostracoda clastic limestone. 61-4 1475.79–1477.54 1.75 Medium dark gray mudstone, horizontal bedding local ostracoda fossils greenish gray

mudstone stripes and lumps on top of the section, with local ostracoda clast limestone lamellae.

61-5 1477.54–1477.74 0.20 Dark greenish gray mudstone, horizontal bedding, few ostracoda fossil. 61-6 1477.74–1478.31 0.57 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil and fossil fragments;

locally with light gray muddy siltstone and greenish gray mudstone stripes and lumps. 61-7 1478.31–1478.44 0.13 Light olive gray mudstone, massive bedding, ostracoda fossil fragments at the bottom, some

medium dark gray mudstone lumps with calcite fillings in contraction fissures. 61-8 1478.44–1478.56 0.12 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil and fossil fragment;

locally light gray mud siltstone and greenish gray mudstone stripes. 61-9 1478.56–1478.78 0.22 Light olive gray mudstone, massive bedding, ostracoda clast limestone lamellae in local site. 61-10 1478.78–1479.58 0.80 Medium dark gray mudstone, horizontal bedding, locally light gray muddy siltstone lamellae. 61-11 1479.58–1479.98 0.40 Medium dark gray mudstone intercalated with medium light gray siltstone, horizontal

bedding, ripple lamination, deformation bedding, convolute bedding; medium light gray siltstone stripes and lamellae.

61-12 1479.98–1482.98 3.00 Medium dark gray mudstone, horizontal bedding, locally with striped mud siltstone; few ostracoda fossil.

61-13 1482.98–1483.55 0.57 Dark greenish gray mudstone, horizontal bedding, few ostracoda fossil and other fossil fragments.

62-1 1483.55–1483.78 0.23 Medium gray mudstone, horizontal bedding, ripple lamination, ostracoda fossils. 62-2 1483.78–1484.55 0.77 Medium dark gray mudstone, horizontal bedding, calcareous siltstone stripes; some irregular

fractures in the upper section, filled with calcite; locally calcareous siltstone lumps. 62-3 1484.55–1485.74 1.19 Olive gray mudstone, horizontal bedding, ostracoda fossil fragments. 62-4 1485.74–1487.77 2.03 Dark gray mudstone, horizontal bedding, ostracoda fossil fragments and ostracoda clast

limestone stripes. 62-5 1487.77–1487.87 0.10 Dark gray ostracoda clast mudstone, ripple lamination with few complete ostracoda fossils. 62-6 1487.87–1489.74 1.87 Dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes, conchonstracan

fossils. 62-7 1489.74–1490.58 0.84 Dark gray mudstone interbedded with medium light gray ostracoda clast limestone, horizontal

bedding, ripple lamination. 62-8 1490.58–1490.97 0.39 Medium dark gray mudstone, horizontal bedding, ripple lamination, ostracoda clasitc

limestone stripes. 62-9 1490.97–1491.58 0.61 Dark gray mudstone intercalated with ostracoda clast limestone, horizontal bedding, ripple

lamination. 62-10 1491.58–1491.99 0.41 Dark gray ostracoda-bearing mudstone, horizontal bedding, few ostracoda clast limestone

stripes. 62-11 1491.99–1492.48 0.49 Dark gray mudstone, horizontal bedding, few ostracoda clast limestone stripes. 62-12 1492.48–1494.30 1.82 Olive gray mudstone, horizontal bedding, ostracoda clast limestone stripes, ripple lamination. 62-13 1494.30–1495.14 0.84 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes, ripple

lamination. 62-14 1495.14–1495.51 0.37 Medium gray mudstone, horizontal bedding, ostracoda clast limestone stripes, ripple

lamination. 62-15 1495.51–1496.09 0.58 Dark gray mudstone, horizontal bedding; ostracoda clast limestone stripes, ripple lamination. 63-1 1496.09–1498.51 2.42 Medium dark gray mudstone, horizontal bedding, few ostracoda clast limestone stripes in the

middle and lower section; fossil fragments on the bedding plane; more conchonstracan fossils at the bottom.

63-2 1498.51–1499.08 0.57 Medium gray mudstone intercalated with light gray ostracoda clast limestone, horizontal bedding, ripple lamination, locally deformation bedding, few calcareous siltstone stripes and lumps.


Continued

63-3 1499.08–1499.59 0.51 Medium gray mudstone, horizontal bedding, fossil fragments, few ostracoda clast limestone stripe.

63-4 1499.59–1499.64 0.05 Medium light gray calcareous siltstone, horizontal ripple lamination, load structure, medium dark gray mudstone stripes.

63-5 1499.64–1503.24 3.60 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes, more conchonstracan fossils and fossil fragments.

63-6 1503.24–1503.57 0.33 Olive gray mudstone, horizontal bedding, more fossil fragments. 63-7 1503.57–1505.12 1.55 Medium dark gray mudstone, horizontal bedding, more fossil fragments. 63-8 1505.12–1506.89 1.77 Olive gray mudstone, horizontal bedding, conchonstracan fossils and fossil fragments. 63-9 1506.89–1507.16 0.27 Light olive gray mudstone intercalated with olive gray mudstone, massive bedding, few

conchonstracan fossil. 63-10 1507.16–1508.09 0.93 Olive gray mudstone, horizontal bedding, ostracoda clast limestone stripes, fossil fragments. 64-1 1508.09–1512.99 4.90 Dark gray mudstone, horizontal bedding, few ostracoda fossil, ostracoda clast limestone and

ostracoda-bearing siltstone stripes in local site; dark greenish gray mudstone and ostracoda clast limestone in the middle; ostracoda clast limestone and light gray calcareous siltstone stripes and lamellae in the lower section.

64-2 1512.99–1513.45 0.46 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil, locally ostracoda clast limestone and ostracoda-bearing siltstone stripes.

64-3 1513.45–1514.99 1.54 Dark gray mudstone, horizontal bedding, few ostracoda fossil. 64-4 1514.99–1516.39 1.40 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil, locally

ostracoda-bearing siltstone and crystalline limestone stripes in local site. 65-1 1516.39–1516.96 0.57 Medium dark gray mudstone, horizontal bedding, more ostracoda fossil fragments. 65-2 1516.96–1517.69 0.73 Dark gray mudstone, horizontal bedding, ostracoda fossil fragments. 65-3 1517.69–1517.96 0.27 Medium light gray ostracoda clast limestone intercalated with laminated medium dark gray

mudstone, olistostromic structure, compressional deformation bedding, ostracoda clast limestone stripes.

65-4 1517.96–1520.76 2.80 Medium dark gray mudstone, horizontal bedding, more ostracoda clasts and fossil fragments. 65-5 1520.76–1523.23 2.47 Medium dark gray ostracoda-bearing mudstone, horizontal bedding, ostracoda fossils and

fragments. 66-1 1523.23–1524.13 0.90 Medium dark gray ostracoda-bearing mudstone, horizontal bedding, more ostracoda fossils in

locally enriched beds, light gray calcareous siltstone lamellae in local site. 66-2 1524.13–1525.73 1.60 Medium dark gray mudstone, horizontal bedding, more ostracoda fossils enriched in local

site, light gray siltstone intercalations. 66-3 1525.73-1525.83 0.10 Medium dark gray mudstone thinly interbedded with light gray calcareous siltstone,

horizontal ripple lamination, few ostracoda fossil. 66-4 1525.83–1527.68 1.85 Medium dark gray ostracoda-bearing mudstone, horizontal bedding, more ostracoda fossils

locally enriched in beds. 66-5 1527.68–1528.78 1.10 Dark gray mudstone, horizontal bedding, locally enriched ostracoda fossil in beds and light

gray siltstone stripes in local site. 66-6 1528.78–1529.88 1.10 Medium dark gray mudstone, indistinct horizontal bedding, more ostracoda fossils enriched in

local site. 66-7 1529.88–1530.73 0.85 Dark gray ostracoda-bearing mudstone, horizontal bedding, more ostracoda fossils, locally

light gray calcareous siltstone stripes. 66-8 1530.73–1531.78 1.05 Medium dark gray mudstone, horizontal bedding, more ostracoda fossils enriched in local

site. 66-9 1531.78–1532.63 0.85 Dark gray ostracoda-bearing mudstone, horizontal bedding, more ostracoda fossils and

calcareous siltstone stripes. 66-10 1532.63–1535.09 2.46 Medium dark gray mudstone, horizontal bedding, more ostracoda fossils enriched in local

site. 66-11 1535.09–1535.19 0.10 Medium dark gray mudstone interbedded with light gray ostracoda clast limestone, horizontal

ripple lamination. 66-12 1535.19–1535.55 0.36 Dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes and lamellae in

local site. 67-1 1535.55–1535.81 0.26 Medium dark gray mudstone, horizontal bedding, ostracoda fossils. 67-2 1535.81–1536.94 1.13 Medium dark gray ostracoda-bearing mudstone, horizontal bedding, few ostracoda clast

limestone stripes and conchonstracan fossil in the lower parts. 67-3 1536.94–1537.44 0.50 Dark gray ostracoda-bearing mudstone, horizontal bedding, few conchonstracan fossil and

ostracoda clast limestone stripes. 67-4 1537.44–1540.65 3.21 Medium dark gray mudstone, horizontal bedding, few conchonstracan fossil and ostracoda

clast limestone stripes. 67-5 1540.65–1542.50 1.85 Dark gray mudstone, horizontal bedding, few ostracoda clast limestone stripes. 67-6 1542.50–1547.78 5.28 Medium dark gray mudstone, horizontal bedding, ripple lamination, ostracoda clast limestone

stripes, ostracoda, and conchonstracan fossils enriched in local beds. 68-1 1547.78–1548.68 0.90 Medium dark gray mudstone, horizontal bedding, ostracoda fossils, and ostracoda clast

limestone stripes in local site.


Continued

68-2 1548.68–1549.43 0.75 Dark gray mudstone, horizontal bedding, ostracoda, and conchonstracan fossils; ostracoda clast limestone lamellae and stripes in local site.

68-3 1549.43–1550.51 1.08 Medium dark gray mudstone, horizontal bedding, more ostracoda fossils, ostracoda clast limestone stripes in local site.

68-4 1550.51–1552.28 1.77 Dark gray mudstone, horizontal bedding, more ostracoda, and conchonstracan fossil fragments; locally ostracoda clast limestone lamellae and stripes; locally conchonstracan fossils enriched.

68-5 1552.28–1552.48 0.20 Medium dark gray mudstone intercalated with light gray calcareous siltstone stripes and lamellae, horizontal ripple lamination, conchonstracan fossils in mudstones, more light gray calcareous siltstone stripes, with a calcareous siltstone lamella in the bottom.

68-6 1552.48–1557.63 5.15 Dark gray mudstone, horizontal bedding, more complete conchonstracan fossils and fragments, locally enriched in beds.

68-7 1557.63–1558.43 0.80 Dark gray ostracoda-bearing mudstone, horizontal bedding, more calcareous siltstone lamellae set in mudstones.

68-8 1558.43–1560.38 1.95 Dark gray mudstone, horizontal bedding, more ostracoda fossils, light gray calcareous siltstone, and light olive gray ostracoda clast limestone stripes and lamellae.

69-1 1560.38–1560.69 0.31 Dark gray mudstone, horizontal bedding, ostracoda fossils, and ostracoda clast limestone stripes and lumps.

69-2 1560.69–1561.26 0.57 Dark gray ostracoda-bearing mudstone, horizontal bedding, ostracoda fossils. 69-3 1561.26–1563.10 1.84 Dark gray mudstone, horizontal bedding, ostracoda, and conchonstracan fossils; ostracoda

clast limestone stripes. 69-4 1563.10–1563.46 0.36 Medium dark gray mudstone with medium light gray ostracoda clast limestone, horizontal

bedding, ripple lamination, ostracoda clast limestone stripes, fossil fragments. 69-5 1563.46–1564.91 1.45 Dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes, ostracoda, and

conchonstracan fossil fragments. 69-6 1564.91–1567.59 2.68 Medium dark gray mudstone, horizontal bedding, few ostracoda clast limestone stripes, and

lamellae. 69-7 1567.59–1568.18 0.59 Light olive gray lime mudstone, massive bedding. 69-8 1568.18–1569.34 1.16 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes with

horizontal ripple lamination and ostracoda fragments on top of the section, few conchonstracan fossils, and other fossil fragments.

70-1 1569.34–1570.30 0.96 Medium dark gray mudstone, horizontal bedding, more ostracoda fossil, and other fossil fragments with plant relics and pyrite grains.

70-2 1570.30–1571.78 1.48 Dark gray mudstone, horizontal bedding, ostracoda clast limestone lamellae unevenly distributed.

70-3 1571.78–1574.34 2.56 Medium dark gray mudstone, horizontal bedding, more ostracoda clast limestone and calcareous siltstone lamellae.

70-4 1574.34–1576.07 1.73 Medium dark gray mudstone, horizontal bedding, ostracoda fossils and plant fossil fragments. 71-1 1576.07–1580.37 4.30 Medium dark gray mudstone, horizontal bedding, more ostracoda unevenly distributed and

locally enriched and conchonstracan fossils, few calcareous siltstone stripes and lamellae. 71-2 1580.37–1581.12 0.75 Medium dark gray ostracoda-bearing mudstone, horizontal bedding, more ostracoda fossils,

plant fossils in the middle. 71-3 1581.12–1581.77 0.65 Dark gray mudstone, horizontal bedding, locally ostracoda fossils enriched more light gray

calcareous siltstone stripes and lumps with horizontal ripple lamination. 71-4 1581.77–1582.97 1.20 Medium dark gray mudstone, horizontal bedding, ostracoda and conchonstracan fossils

enriched in local site. 71-5 1582.97–1585.97 3.00 Dark gray mudstone, horizontal bedding, ostracoda and conchonstracan complete fossils and

fragments in local site, few light olive gray ostracoda clast limestone stripes, and lamellae. 71-6 1585.97–1586.52 0.55 Medium dark gray mudstone, horizontal bedding, ostracoda fossils in local site, few plant

fossil fragments. 71-7 1586.52–1588.23 1.71 Dark gray mudstone, horizontal bedding, ostracoda and conchonstracan fossils in local site;

with local light olive gray ostracoda clast limestone stripes and lamellae. 72-1 1588.23–1589.10 0.87 Dark gray mudstone, horizontal bedding, ostracoda and conchonstracan fossils locally

enriched. 72-2 1589.10–1589.26 0.16 Medium light gray calcareous siltstone with medium dark gray laminated mudstone,

horizontal ripple lamination, compression deformation bedding, local lyconvolute bedding; climbing-ripple lamination on top of the upper section; ostracoda fossil fragments, sand pillows and balls.

72-3 1589.26–1590.09 0.83 Dark gray mudstone, horizontal bedding, ostracoda fossils; a vertical fracture separating the core into two parts, fracture surface covered by calcite, the crystal surface is covered by oil film; few conchonstracan fossil.

72-4 1590.09–1590.93 0.84 Medium dark gray mudstone, horizontal bedding, ostracoda fossils; a vertical fracture separated the core into two parts, fracture surface covered by calcite, the surface of which is covered by oil film; few conchonstracan fossil.

72-5 1590.93–1591.73 0.80 Medium dark gray mudstone intercalated with medium light gray laminated calcareous siltstone, horizontal bedding, ripple lamination, locally convolute bedding, calcareous siltstone stripes, sand pillow, sand balls.


Continued

72-6 1591.73–1593.26 1.53 Dark gray mudstone, horizontal bedding, ostracoda fossils, few calcareous siltstone stripes. 72-7 1593.26–1593.70 0.44 Medium dark gray mudstone, horizontal bedding, ostracoda fossils. 72-8 1593.70–1595.26 1.56 Dark gray mudstone, horizontal bedding, few ostracoda clast limestone stripes,

conchonstracan fossils enriched on the bedding plane and more fossil fragments. 72-9 1595.26–1598.23 2.97 Medium dark gray mudstone, horizontal bedding, few ostracoda clast limestone stripes,

conchonstracan fossils enriched on the bedding plane and more fossil fragments. 73-1 1598.23–1598.52 0.29 Medium dark gray mudstone, horizontal bedding, more fossil fragments. 73-2 1598.52–1599.25 0.73 Dark gray mudstone, horizontal bedding, light gray calcareous siltstone stripes on top of the

upper section. 73-3 1599.25–1600.85 1.60 Olive gray mudstone, horizontal bedding, more fossil fragments enriched in individual

bedding planes. 73-4 1600.85–1600.98 0.13 Dark gray mudstone, disturbed bedding, ripple lamination, more calcareous siltstone lumps,

stripes. 73-5 1600.98–1602.23 1.25 Olive gray mudstone, horizontal bedding, more fossil fragments enriched in bedding planes. 73-6 1602.23–1603.33 1.10 Medium dark gray mudstone, more fossil fragments, conchonstracan enriched in planes and

ostracoda fossils, calcareous siltstone stripes and lumps; on top of the scouring surface are calcareous siltstone lamellae with fossil fragments.

73-7 1603.33–1607.34 4.01 Olive gray mudstone, horizontal bedding, more fossil fragments and conchonstracan fossils enriched in bedding planes, few calcareous siltstone stripes, lumps.

73-8 1607.34–1607.92 0.58 Dark gray mudstone, horizontal bedding, fossil fragments, calcareous siltstone strip in the basal part of the section.

73-9 1607.92–1610.26 2.34 Medium dark gray mudstone, horizontal bedding, fossil fragments, ostracoda fossils, few light gray calcareous siltstone stripes conchonstracan fossils.

73-10 1610.26–1610.31 0.05 Light gray calcareous siltstone thinly interbedded with medium dark gray mudstone, ripple lamination on top of the upper section, disturbed bedding in the middle and lower section, locally light gray calcareous siltstone lumps and stripes.

73-11 1610.31–1610.49 0.18 Dark gray mudstone, horizontal bedding, few ostracoda fossil. 74-1 1610.49–1612.70 2.21 Medium dark gray mudstone, horizontal bedding, more ostracoda and conchonstracan fossils

enriched locally. 74-2 1612.70–1613.11 0.41 Medium gray mud siltstone, massive bedding, locally horizontal ripple lamination, more

ostracoda and conchonstracan fossils, ostracoda clast limestone stripes. 74-3 1613.11–1614.99 1.88 Dark gray mudstone, horizontal bedding, ostracoda and conchonstracan fossils, ostracoda

clast limestone stripes in local site. 74-4 1614.99–1615.76 0.77 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil and other fossil

fragments. 74-5 1615.79–1616.09 0.30 Medium dark gray mudstone with medium gray ostracoda clast limestone, ripple lamination,

more ostracoda clast limestone stripes and lamellae. 74-6 1616.09–1616.64 0.55 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil and plant fossil

fragment. 74-7 1616.64–1616.83 0.19 Dark gray mudstone, horizontal bedding, plant fossil fragments, locally enriched. 74-8 1616.83–1616.85 0.02 Olive gray oilshale, lamellation structure. 74-9 1616.85–1617.09 0.24 Dark gray mudstone, horizontal bedding, plant fossil fragments locally enriched. 74-10 1617.09–1618.61 1.52 Medium dark gray mudstone, horizontal bedding; complete ostracoda, conchonstracan fossils

and plant fossil fragments. 74-11 1618.61–1619.11 0.50 Medium dark gray mudstone intercalated with medium dark gray ostracoda clast limestone

and medium light gray calcareous siltstone, horizontal ripple lamination, more ostracoda clast limestone and calcareous ostracoda-bearing siltstone stripes.

74-12 1619.11–1620.97 1.86 Dark gray mudstone, horizontal bedding, few ostracoda fossils. 75-1 1620.97–1621.11 0.14 Dark gray mudstone, horizontal bedding. 75-2 1621.11–1621.47 0.36 Medium dark gray mudstone, horizontal bedding, abundant conchonstracan fossils and

calcite-bearing siltstone stripes. 75-3 1621.47–1621.77 0.30 Light olive gray dolomite, massive bedding, ostracoda and conchonstracan fossils in

individual bedding planes. 75-4 1621.77–1623.22 1.45 Dark gray mudstone, horizontal bedding, locally horizontal ripple lamination few ostracoda

and conchonstracan fossil in individual beds; light gray calcareous siltstone stripes and a nearly vertical fracture.

75-5 1623.22–1624.17 0.95 Olive gray mudstone, horizontal bedding, fossil fragments, with few conchonstracan fossils; ostracoda fossils.

75-6 1624.17–1625.21 1.04 Medium dark gray mudstone intercalated with medium light gray muddy laminated siltstone, horizontal bedding, ripple lamination, ostracoda and conchonstracan fossils enriched on the bedding planes.

75-7 1625.21–1627.69 2.48 Dark gray mudstone, horizontal bedding, with dolomite lamellae, few ostracoda and conchonstracan fossils.

76-1 1627.69–1628.24 0.55 Dark gray mudstone, horizontal bedding, dolomite lamellae, with a few ostracoda and conchonstracan fossils.


Continued

76-2 1628.24–1629.59 1.35 Dark gray mudstone interbedded with light gray ostracoda clast limestone, ripple lamination, ostracoda clast limestone stripes, oil-bearing in local site; calcite and pyrite in ostracoda clast limestone stripes and lamellae.

76-3 1629.59–1633.44 3.85 Medium dark gray mudstone, horizontal bedding, light gray and olive gray dolomite lamellae in middle cross section a complete animal fossil is found; pyrite lumps in local site.

76-4 1633.44–1634.79 1.35 Dark gray mudstone, horizontal bedding, few ostracoda fossil, dolomite lamellae. 76-5 1634.79–1636.64 1.85 Medium dark gray mudstone, horizontal bedding, few ostracoda and conchostracan fossils

locally enriched, few ostracoda clast limestone stripes. 76-6 1636.64–1636.72 0.08 Light olive gray dolomite, massive bedding. 76-7 1636.72–1639.11 2.39 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone lamellae and

stripes in local site; few light gray calcareous siltstone lamella. 77-1 1639.11–1639.74 0.63 Medium gray mudstone, horizontal bedding, more ostracoda clast limestone and calcareous

siltstone stripes; fossil fragments in local site. 77-2 1639.74–1639.99 0.25 Medium dark gray mudstone, horizontal bedding, ostracoda and other fossils fragments. 77-3 1639.99–1640.66 0.67 Medium gray marlite, massive bedding, more fractures, filled with calcite. 77-4 1640.66–1641.06 0.40 Medium dark gray mudstone, horizontal bedding, few fossil fragment. 77-5 1641.06–1642.41 1.35 Dark gray mudstone, horizontal bedding, few ostracoda fossil and carbonized fossil fragments. 77-6 1642.41–1643.16 0.75 Medium gray mudstone, horizontal bedding, ostracoda and other fossils fragments; medium

gray mudstone and olive gray bioclast limestone stripes and lumps. 77-7 1643.16–1643.81 0.65 Medium dark gray mudstone, horizontal bedding, ostracoda clast limestone stripes in the

lower section, more ostracoda fossils enriched in local site. 77-8 1643.81–1645.71 1.90 Dark gray mudstone, horizontal bedding, few ostracoda fossil and olive gray dolomite lamella. 77-9 1645.71–1646.01 0.30 Medium dark gray mudstone, horizontal bedding, more ostracoda fossils and fossil fragments.

78-1 1646.01–1646.27 0.26 Medium dark gray mudstone, horizontal bedding, more ostracoda fossils and calcareous siltstone lamellae.

78-2 1646.27–1647.01 0.74 Dark gray mudstone, horizontal bedding, ostracoda fossils. 79-1 1647.10–1647.71 0.61 Dark gray mudstone, horizontal bedding, more calcareous siltstone lamellae, ichnofossils and

fossil fragments. 79-2 1647.71–1652.77 5.06 Dark gray mudstone, horizontal bedding, ostracoda and conchostracan fossils; fossil

fragments enriched in individual bedding plane; a vertical fracture, filled with calcite. 79-3 1652.77–1653.86 1.09 Medium dark gray mudstone, horizontal bedding, pyrite at the top, dolomite lamellae. 79-4 1653.86–1653.93 0.07 Medium dark gray ostracoda mudstone, ripple lamination, deformation bedding. 79-5 1653.93–1654.22 0.29 Dark gray mudstone thinly interbedded with dark gray ostracoda-bearing mudstone,

horizontal bedding, ripple lamination. 79-6 1654.22–1655.01 0.79 Dark gray mudstone, horizontal bedding, trace fossils. 79-7 1655.01–1655.62 0.61 Dark gray ostracoda-bearing mudstone, horizontal bedding, ostracoda fossils, few trace fossil;

with 1.5 cm ostracoda clast limestone in the basal part. 79-8 1655.62–1657.50 1.88 Dark gray mudstone, horizontal bedding, few ostracoda clast limestone lamella, with

ostracoda fossils. 80-1 1657.50–1657.58 0.08 Grayish black silica mudstone, massive bedding. 80-2 1657.58–1659.63 2.05 Dark gray mudstone, horizontal bedding, conchostracan fossils, fossils fragments enriched in

certain bedding planes, olive gray dolomite lamellae in local site. 80-3 1659.63–1659.77 0.14 Dark gray mudstone thinly interbedded with light gray calcareous siltstone, ripple lamination,

deformation bedding and convolute bedding, sand pillows and ball structures, irregular calcareous siltstone stripes and lumps.

80-4 1659.77–1659.98 0.21 Dark gray mudstone, horizontal bedding; light gray calcareous siltstone stripes with horizontal ripple lamination.

80-5 1659.98–1660.41 0.43 Dark gray mudstone interbedded with light gray calcareous siltstone, interrupted horizontal ripple lamination, convolute bedding and deformation bedding with sand dykes penetrated into calcareous siltstone stripes.

80-6 1660.41–1662.75 2.34 Dark gray mudstone, horizontal bedding, few fossil fragments. 80-7 1662.75–1662.97 0.22 Dark gray mudstone with light gray siltstone, horizontal bedding, convolute bedding,

interrupted ripple lamination and deformation bedding, fossil fragments in mudstones. 80-8 1662.97–1665.93 2.96 Dark gray mudstone, horizontal bedding, few fossil fragment. 80-9 1665.93–1666.09 0.16 Dark gray mudstone interbedded with light gray siltstone, horizontal ripple lamination and

convolute bedding, deformation structure and olistostromic structure with whirl style in local site; calcareous siltstone stripes.

80-10 1666.09–1667.50 1.41 Dark gray mudstone, horizontal bedding, calcareous siltstone stripes and fossils. 80-11 1667.50–1667.66 0.16 Olive black dolomite, massive bedding. 80-12 1667.66–1668.03 0.37 Medium dark gray mudstone with laminated light gray calcareous siltstone, horizontal ripple

lamination, sand pillow and ball structures, calcareous siltstone stripes and lumps. 80-13 1668.03–1669.65 1.62 Dark gray mudstone, horizontal bedding, few olive gray dolomite lamella. 80-14 1669.65–1669.75 0.10 Olive black dolomite, massive bedding.


Continued

80-15 1669.75–1671.87 2.12 Dark gray mudstone, horizontal bedding; light gray calcareous siltstone lamellae and lumps in local site with horizontal ripple lamination, ostracoda fossils and fossil fragments.

81-1 1671.87–1672.10 0.23 Dark gray mudstone, horizontal bedding, pyrite stripes. 81-2 1672.10–1676.87 4.77 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil and fossil fragment;

locally light gray calcareous siltstone stripes, lumpsand lamellae; a doubted greenish grey tuff bed, 0.5 cm thick, in the upper section.

81-3 1676.87–1678.73 1.86 Dark gray mudstone, horizontal bedding, ostracoda fossils enriched in local site, few olive gray dolomite and light gray siltstone lamella.

82-1 1678.73–1679.67 0.94 Medium dark gray mudstone, horizontal bedding, ostracoda fossil, few carbonized plant fossil fragment, locally light gray calcareous siltstone stripes and lamellae.

82-2 1679.67–1681.10 1.43 Dark gray mudstone, horizontal bedding, ostracoda fossils locally enriched, few carbonized plant fossil fragment, calcareous siltstone lamella, stripes and lumps in local site.

82-3 1681.10–1681.67 0.57 Medium dark gray mudstone with light gray calcareous siltstone and olive gray ostracoda clast limestone, horizontal bedding, ripple lamination intercalated with many ostracoda clastic rocks and calcareous siltstone lamellae, stripes and lumps.

82-4 1681.67–1686.07 4.40 Medium dark gray mudstone, horizontal bedding, calcareous siltstone stripes and lamellae, ostracoda fossil enriched beds, few pyrites stripes.

82-5 1686.07–1686.29 0.22 Medium dark gray mudstone with ostracoda clast limestone, horizontal bedding, ripple lamination, light gray calcareous siltstone stripes in the upper section, an ostracoda clast limestone lamella in the lower section.

82-6 1686.29–1689.17 2.88 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil and carbonized plant fossil fragments, thin-bedded olive gray dolomite.

82-7 1689.17–1689.23 0.06 Olive black dolomite, horizontal bedding. 82-8 1689.23-1690.33 1.10 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil and carbonized plant

fossil fragments. 82-9 1690.33–1690.41 0.08 Olive black dolomite, massive bedding, convolute deformation bedding in the basal part. 82-10 1690.41–1690.77 0.36 Medium dark gray mudstone, horizontal bedding, few ostracoda fossil and calcareous

siltstone stripe. 83-1 1690.77–1691.22 0.45 Dark gray mudstone, horizontal bedding, few fossil fragments, light gray calcareous siltstone

stripes which locally penetrating down into the mudstone. 83-2 1691.22–1692.05 0.83 Medium dark gray mudstone, light gray calcareous siltstone lens and fossil fragments. 83-3 1692.05–1692.19 0.14 Olive black dolomite, indistinct horizontal bedding. 83-4 1692.19–1693.54 1.35 Dark gray mudstone, horizontal bedding locally horizontal ripple lamination in the light gray

calcareous siltstone stripes; carbonized plant and conchostraca fossils in local bedding plane. 83-5 1693.54–1693.90 0.36 Dark gray mudstone interbedded with laminated light gray calcareous siltstone; interrupted

ripple lamination, deformation bedding and convolute bedding, with sand pillows and balls; the original beddings preserved within the sand bodies, some fossil fragments.

83-6 1693.90–1697.00 3.10 Dark gray mudstone, horizontal bedding, few trace fossil, thin-bedded calcareous siltstone in the middle.

83-7 1697.00–1697.07 0.07 Olive black dolomite, massive bedding. 83-8 1697.07–1698.98 1.91 Dark gray mudstone, horizontal bedding, some fossil fragments, two crystalline limestone

interlayers in the middle, few calcareous siltstone stripes. 83-9 1698.98–1699.06 0.08 Olive black dolomite, massive bedding. 83-10 1699.06–1699.86 0.80 Dark gray mudstone, horizontal bedding, few fossil fragment; thin-bedded crystalline

limestone in the lower section, few light gray calcareous siltstone stripe. 83-11 1699.86–1700.01 0.15 Olive black dolomite, massive bedding. 83-12 1700.01–1700.29 0.28 Dark gray mudstone, horizontal bedding, few fossil fragment. 83-13 1700.29–1700.80 0.51 Dark gray mudstone thinly interbedded with light gray calcareous siltstone, horizontal

bedding, calcareous siltstone stripes. 83-14 1700.80–1701.52 0.72 Dark gray mudstone, horizontal bedding, few calcareous siltstone stripe.

Underlying formation: the first member of the Qingshankou Formation, conformity

thin-bedded, some are of very small thickness, and lower occurrence frequency (Fig. 2).

Two sedimentary subfacies, include semi-deep lake and shallow lake, and ten sedimentary microfacies can be identified in the second and third member of the Qingshankou Formation. The semi-deep lake subfacies including semi-deep lake mudstone (plate -1, plate -2), dolomite (plate -3), marl (plate -4), limestone (plate -5), oil shale (plate -6), semi-deep lake turbidity (plate -7, plate -8), volcanic ash (plate -9) and seismite (plate -10) sedimentary microfacies.

The shallow lake subfacies includes shallow lake mudstone (plate -11) and shallow lake turbidity (plate -12) sedimentary microfacies[15]. The mudstone sediments of semi-deep lake subfacies is the background sediments of the lake environment, and other kinds of microfacies, such as turbidite and dolomite sediments are depositional events in the second and third member of the Qiangshankou Formation.

The sedimentary sequence of CCSD-SK- s shows different cycle orders of lithology and lithofacies in the second and third member of the Qingshankou Formation. The six types of


Fig. 1 Columnar section of high resolution lithology-cyclic stratigraphy and sedimentary facies of the second and third member of the Qingshankou Formation (CCSD-SK- s)

* GSA Rock-Color Code is from Geological Society of America rock-color chart, and it is a common criteria for drilling rock color description in IODP N9–white; N8–very light grey; N7–light grey; N6–medium light grey; N5–medium grey; N4–medium dark grey; N3–dark grey; N2–grayish black; 5GY 8/1–light greenish grey; 5GY 6/1–greenish grey; 5GY 4/1–dark greenish grey; 5GY 5/2–dusty yellow green; 10GY5/2–grayish green; 5G8/1–light greenish gray; 5G6/1–greenish gray; 5G4/1–dark greenish gray; 5G2/1–greenish black; 5G5/2–grayish green; 5Y6/1–light olive gray; 5Y4/1–olive gray; 5YR2/1–olive black; 5YR4/1–brownish gray; 5YR2/2–dusky brown; 5YR3/2–grayish brown; 5YR5/2–pale brown; 10YR6/2–pale yellowish brown; 10YR4/2–dark yellowish brown; 10YR2/2–dusky yellowish brown; 10R6/2–pale red; 10R4/2–grayish red; 5P4/2–grayish purple.


Fig. 2 Occurrence frequency and thickness percentage of drilling core lithology of the second and third member of the Qingshankou Formation (CCSD-SK- s)

Plate Plate showing main lithologies and sedimentary facies of the second and third member of the Qingshankou Formation in CCSD-SK- s 1 dark gray mudstone, horizontal bedding, mudstone of still water in semi-deep lake, the second and third member of the Qingshankou Formation, well depth: 1613.49 m. 2 dark gray ostracoda-bearing mudstone, horizontal bedding, mudstone of still water in semi-deep lake, the second and third member of the Qingshankou Formation, well depth: 1655.05 m. 3 olive gray dolomite, massive bedding, dolomite sedimentary microfacies, the second and third member of the Qingshankou Formation, well depth: 1699.02 m. 4 light olive gray marl, massive bedding, marl sedimentary microfacies, the second and third member of the Qingshankou Formation, well depth: 1640.00 m. 5 white crystalline limestone, massive bedding, limestone sedimentary microfacies, the second and third member of the Qingshankou Formation, well depth: 1515.14 m. 6 olive gray oil shale, lamellation structure, oil shale sedimentary microfacies, the second and third member of the Qingshankou Formation, well depth: 1616.85m. 7 medium light gray calcareous siltstone, ripple lamination, convolute bedding in local site, turbidite microfacies in semi-deep lake, the second and third member of the Qingshankou Formation, well depth: 1589.18m. 8 light gray ostracoda clast limestone, turbidite in semi-deep lake, the second and third member of the Qingshankou Formation, well depth: 1686.28 m. 9 volcanic ash, the second and third member of the Qingshankou Formation, well depth: 1673.04 m. 10 light gray calcareous siltstone, seismite sedimentary microfacies, the second and third member of the Qingshankou Formation, well depth: 1660.00m. 11 grayish brown mudstone, massive bedding, mudstone of still water in shallow lake, the second and third member of the Qingshankou Formation, well depth: 1292.10m. 12 light gray calcareous siltstone lamellae and stripes in greenish gray mudstone, shallow lake turbidite, the second and third member of the Qingshankou Formation, well depth: 1288.30m.


meter-scale cycles recognized in the member are mudstone-sandy turbidite sediments, mudstone -ostracoda clast turbidity current, marl-mudstone sediments, dolomite-mudstone sediments, mudstone-seismite sediments and oil shale-mudstone. There are 422 meter-scale cycles (sixth-order cycle) recognized in the second and third member of the Qingshankou Formation, 130 fifth-order cycles, 21 fourth-order cycles and 1 third-order cycles. In average, 3 or 4 meter-scale cycles are superposed forming a fifth order cycle, and 4 to 5 fifth order cycles are superposed forming a fourth order cycle. Each of the fifth order cycle presents a process of variation in accommodation space: increasing first and then decreasing. The fourth order cycles and the superposition of the fourth order cycles experienced the similar process.

4 Discussion and conclusions

4.1 General sequence characteristics of the second and third member of the Qingshankou Formation

The second and third members of the Qingshankou Formation in the CCSD-SK- s are lacustrine sediments, there are 12 lithological types of rocks, 2 subfacies (semi-deep lake and shallow lake) and 6 kinds of microfacies. The main types of rocks are dark gray, medium dark gray, greenish gray and dark green mudstone and ostracoda-bearing mudstone. The sedimentary sequence of the second and third member of the Qingshankou Formation is in cycle. There are 422 meter-scale cycles (sixth-order cycle), 130 fifth-order cycles, 21 fourth-order cycles and 1 third-order cycles.

4.2 Whole cores of the second and third member of the Qingshankou Formation described in centimeter level provide abundant data for researches on source rocks in the Songliao Basin

The distribution of source rocks in the second and third member of the Qingshankou Formation is much narrower than that in the first member. The source rocks which lay on the lower part of the second and third member are mainly developed in the Central Depression, and the thickness is thinner than that of the first member. The previous target bed of coring in the Songliao Basin is mainly concentrated at reservoir rather than source bed and cap rocks which limits the systematic research on source rocks. Dark mudstone in lower part of the second and third member of the Qingshankou Formation are well-developed, and the core recovery is 100%. Thus, it provides abundant and continuous core information for researches on source rocks in the second and third member of the Qingshankou Formation in the Songliao Basin.

4.3 Significance of the centimeter level description of the whole second and third member of the Qingshankou Formation on researching lake depositional events in Songliao Basin

Several layers of seismite are identified in the middle and

lower part of second and third member of the Qingshankou Formation, CCSD-SK- s. The thickness of the seismite is generally between several centimeters to dozens of centimeters. They are all intercalated with dark mudstone, and belong to deep water sediments. On the basis of the study of seismite sequence, it is probably related to the volcanic activities in the second and third member of the Qingshankou Formation. There are many reports about volcanic activities in the Qingshankou Formation, Songliao Basin[16,17]. The researches on seismite provide reference for the evolution of the Songliao Basin in depression period. Besides, the dolomite, limestone, volcanic ash and ostracoda clast limestone are identified in the second and third member of Qingshankou Formation, CCSD-SK- s. It’s more comprehensive compared to those event layers previously discovered in other drilling cores and sections. The relevant researches on these event layers are significant for the study of depositional events in the Songliao Basin.

Acknowledgments

We are grateful to all the participants including all engineering staffs and researchers of CCSD-SK- for their hard work. This work was supported by the National Basic Research Program of China (NO. 2006CB701403). References [1] National Stratigraphy Council. Compilation of National Sratigraphy

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description of cretaceous sedimentary sequence ofthe second and third member of the...

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