Reservoir Character and Main Control Factors

in the Upper Second Member of Shahejie

Formation(Es2) in the Linnan Subsag

Reporter: Feng Yuelin

Co-supervisor: Song Guoqi

Major: Hydrocarbon Accumulation

Contents

1.Introduction

2.Sedimentary character in study area

3.Reservoir assessment in study area

4.Conclusion and thought

1 Introduction

Lin nan subsag located in the west of Huimin sag, the southeast of

the Bohai Bay basin, which an important petroliferous basin of China.

The Linnan subsag The Huimin sag The Bohai Bay Basin

Proved reserves of each member in Linnan Susag

Proved reserves of Es2

Contents

1.Introduction

2.Sedimentary character in study area

3.Reservoir assessment in study area

4.Conclusion and thought

J202 3704.55m

Parallel bedding

J202 3763.5m

Boring porisity

J202 3680.77m

Parallel bedding

JX2 3818.51m

Parallel bedding

X33 3256.6m

Coarse sand X53 2980.33m

Parallel bedding

X53 2980.53m

Cross bedding

X70 3266.46m

Wavy ripple

cross-bedding

X33 X53

JX2

J202

X70

2 Sedimentary Character

T2

T3

T6

T4

SP R25

J4 X704

SP R25

X704 J3 J4 J5 X39 X99 S547 S546

Distributary shape

Bell-shaped Funnel shape

Fluvial facies

Delta sedimentary facies

Es2

Shuang Feng Area Jiang Jiadian Area Wa Wu Area

Braided delta facies progradating to

the central depression

Braided delta facies Braided delta facies

Braided fluvial facies Braided delta facies

Early stage: braided fluvial facies, the

sandbody connected well

Later stage: covered by channel sand,

vertical overlay but lateral connected

poor

Sand thickness isopach map

The thickness of sand increased especially at the Shuang Feng district

Contents

1.Introduction

2.Sedimentary character in study area

3.Reservoir assessment in study area

4.Conclusion and thought

3 Reservoir Assessment Sorting

Overwater distributary channel

Underwater distributary channel

Delta front mouth bar

Braided river channel sand

3 Reservoir Assessment

Overwater distributary channel

Underwater distributary channel Delta front mouth bar

Braided river channel sand

Psephicity

Round

Round Round

Round

Semiround

Semiround Semiround

The type of

motherrock

The type of

lay mineral

Magmatic

rock

Metamorphic

rocks

Sedimentary

rocks

kaolinite illite chlorite

Overwater distributary channel：lithic feldspar

sandstone and feldspar lithic sandstone

Underwater distributary channel： lithic

feldspar sandstone

Delta front mouth bar： lithic feldspar

sandstone

Braided river channel sand:lithic feldspar

sandstone

X70-2687.6m-Calcite cementation J3，3713.7m-Ankerite cement

X70-3074.3m-Ankerite cement X33，3293.12m-Dolomite cementation cementation

Macropore：interparticle porosity、intercrystalline pore、dissolved pore

Micropore：Kaolinite intercrystal pore

Feldspar dissolved pore

Classification of pore

微孔隙

粒间孔

长石溶孔

街斜2，3779.4- 长石颗粒溶解，200x（-）

Abundant of primary porosity, the solution porosity occurred in Yingzijie area

J202,3767.1m, residual primary

interparticle porosity pore,100×（-

）

X33,3295.5m, kaolinite

intercrystalline pore,200×（-） J202,3773.4m, primary interparticle

porosity pore,200×（-）

J3,3716.8m, kaolinite

intercrystalline pore,200×（-） Jx2,3779.4.6m, kaolinite solution

pore,200×（-）

J202,3795.6m, kaolinite marginal

solution pore,200×（-）

well Depth m

Prosity （%）

permeability ×10-3µm2

The pore radius

µm

Max of pore radius

µm

Hg(50%)MPa Hg(max)%

average coefficient of

variation

X70

3264.4 16.2 211 6.83 22.03 0.29 86.09 0.99

3267.71 17.9 34.6 2.39 5.95 0.56 80.37 0.75

3268.58 17.8 87.8 3.65 10.02 0.44 82.17 0.84

X32 3290.52 18.9 113.7 4.48 13.53 0.38 84.15 0.88

3291.39 19.6 289.3 6.43 13.99 0.26 83.96 0.83

X70 3264.4m X70 3267.7m

Section conclusion

1. Sedimentary facies of Es2 is from braided river delta change into

braiding river

2. The main reservoir types are Overwater distributary channel

reserviors, underwater distributary channel reservoirs, delta

front mouth bar reservoirs and braided river channel sand

reservoirs.

3. The five types of reservoirs have good condition to accumulate

hydrocarbons or to become the migrate pathways.

Contents

1.Introduction

2.Sedimentary character in study area

3.Reservoir assessment in study area

4.Conclusion and thought

25%-27% 15%-17% 19%-23%

31%-33% 31%-36% 36%-43%

17%-27%

X705 X321 X704 J3 J4 J206 J204 L98 L981 L86 Ls1

Xx961 Xx96 X906

4 Conclusion and thought

The sand in upper Es2 connected well and good physical property. The connected sandbody can become the good hydrocarbon migration layer .

Fault 1、transporting

2、sealing

Hydrocarbon accumulation model

Hydrocarbon migrate along the fault and accumulate in the traps.

Xx96 x906

100米

110米

150米

130米 90米

180米

100米

210米

300米

130米 150米

160米

150米

100米 50米

10米

150

200

250 300

100

50

0

夏90

夏斜502

150米

30米

20米

夏47

夏460

夏906

夏96

Fault sealing mode

Oil Reservoirs Profile in Linan Subsag

Map of fault throw distribution

The sedimentary facies in the Linnan subsag of Es2 changes from braided delta facies to

braided fluvial facies. There exist five types of reservoirs, each reservoir has its own

character. In the center Linnan subsag, the layers besides the fault vertically has great

conducting condition, in the frontier of the basin, hydrocarbon migrate laterally along the

sand. The burial of Es2 is relative shallow. Under the effect of the fault sealing, the thin

sand is more liable to accumulate the hydrocarbon and the thick sand is more liable to

become the hydrocarbon migration pathways.

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