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Scientific report
regarding the project implementation from January 2014 – December 2014
Geogenic greenhouse gas emissions from geothermal and petroleum systems – application
to Romania
PN‐II‐ID‐PCE‐2011‐3‐0537
The activities from January 2014 – December 2014 are associated to work packages 2, 3 and 4 from the
project implementation plan.
WP2. Field investigation and laboratory analyses
In 2014, the field investigations were carried out in the central and eastern part of Transylvania, Southern
Carpathians Foredeep (Olanesti) and Eastern Carpathians (Balvanyos) (fig.1).
The area of Sarmasel (central Transylvania) was investigated in order to observe the changes of gas intensity
that appeared during time.
A detailed field campaign was performed in Eastern Transylvania, in order to investigate the gas emissions at
the border between Transylvanian Basin and the Eastern Carpathians. In this area, some locations from Mures,
Harghita and Covasna County were investigated, but only eight locations were found to release gas. The gas
manifestations consist of two mud volcanoes from Maia village, with a low degasing activity; one mud volcano
from Candu village with low degassing; one inactive mud volcano from Atid village; two seeps at Corund with
low amount of methane; a dry seep at Goagiu; and one mud volcano at Forteni, also with a low rate of gas
emission. Another investigated area is Baile Dungo, and we re‐evaluated the total emission from Baile
Homorod mud volcanoes (fig. 2). The total emission of CO2 and CH4 was measured for all the locations
mentioned above.
Fig. 1. The areas investigated in 2014 (orange outline)
Water samples were collected from 20 springs which are located in the area of the following villages: Corund,
Baile Homorod, Lueta, Meresti, Baile Selters and Baile Chirui. The aim of these investigations was to study the
origin of methane in the area of post volcanic activity. The water samples will be analyzed at INGV Rome for 13C/12C isotopic ratio and molecular composition of dissolved gases.
Fig. 2. Spatial distribution of mud volcanoes from Baile Homorod (Brasov County)
At Balvanyos, the gas samples were collected in special containers that were sent for analyses at CNRS Nancy.
The isotopic composition of these samples will be analyzed through high resolution methods, which could
generate very interesting results in what concerning the degassing mechanism in the area; this could also
open new international collaboration.
In 2013, a number of 50 samples were collected from the following locations: Caciulata‐Calimanesti, Baile
Govora, Baile Olanesti, Slanic‐Moldova, Bihor area and South Transylvania. In February 2014, these samples
were analyzed at INGV Rome laboratory. The gases were extracted from solution through agitation and
analyzed with several analytical instruments. In the first stage, a portable flux meter (West Systems,
Pontedera, Italy) was used to analyze the CH4 and CO2 concentrations. This device is equipped with a TDLAS
sensor for CH4 (tunable diode laser absorption spectroscopy) with a measuring range of 0.1 ppmv up to 100%
v/v, repeatability of 0.1 ppmv. The CO2 detector is a double beam infrared sensor with a range of 0‐20,000
ppmv, the accuracy of 2% and a repeatability of ±5 ppmv.
At INGV laboratory, the FTIR GASMET DX‐4030 (Gasmet Finlanda) device was also used. The device has a
spectral data base to analyze 13 gases simultaneously (CH4, CO2, CO, H2O, C2H6, C3H8, n‐C4H10, i‐C4H10, n‐C5H12,
i‐C5H12, C6H6, COS and SO2). The device has an accuracy of 10‐20%, and a limit of detection of 1 ppmv. A
hydrogen detector (Huberg type) which has the limit of detection of 5 ppmv was also used.
An isotopic analyzer (Picarro G2112‐I) was used for carbon‐13 analyses, which uses the Cavity Ring Down
Spectroscopy (CRDS) principle and has the following characteristics: precision <0.7‰ at 1.8 ppmv CH4, 1σ
<0.4‰ at 20 de ppmv.
Geochemical interpretations (WP3)
The geogenic gases are characterized by their molecular and isotopic composition which has become an
important geochemical tool to study the genesis of hydrocarbon reservoirs. Although Romania is one of the
European countries with the most abundant hydrocarbon reserves, which played an important role during the
industrial development, the previous studies were based only on molecular composition of gas, including the
excellent work Geochemistry of natural gases of Filipescu and Huma (1979). Before 2008, when the first
complete analysis of some gas samples from Bacau area appeared (Baciu et al., 2008) there were no published
data. Afterwards, more data was published by the group of researchers from Babes‐Bolyai University of Cluj‐
Napoca, in collaboration with INGV Rome (Etiope et al., 2009, 2011, Etiope and Baciu, 2010, Spulber et al.,
2010).
Fig. 3. Bernard diagram fot the main locations with isotopic data from Romania
Currently, the research group mentioned above collected an important set of molecular and isotopic data
base, which will be syntetised and published in an international prestigious journal. An example of diagram
which includes these results is presented in fig 3. The results mainly fit to the field of microbial and
thermogenic origin. The gases from the Transylvanian Basin have a microbial origin (Sarmasel, Deleni). In the
Eastern part of Transylvania, the mud volcanoes from Homorod indicate very unusual characteristics, beyond
the normal limits of the compositional characteristics. This location sets a new world record of helium and
nitrogen content, and deuterium ratio of methane (Etiope et al., 2011). The other investigated gases have
mainly thermogenic origin.
Fig. 4. Bernard diagram of gas samples from waters
Gas samples from water were collected from Carpathians area, Transylvanian Basin, Moldavian Platform, and
the results were interpreted. The carbon‐13 was analysed for a number of 56 samples, from a total of 110
collected. For the remaining samples, the methane concentration was too low to be analysed. The dissolved
gases from Transylvania have a microbial origin, which is similar with all the other isotopic data from other
sources (seeps, mud volcanoes); in Bihor, the dissolved gases are of microbial/mixed origin; in the Olt Valley
area and in Baile Herculane the methane shows a thermogenic origin, with some cases of abiotic origin.
It is interesting to highlight that radon rich springs have low amounts of methane (which is of thermogenic
origin), and in springs with low amount of radon, the dissolved methane is higher. This complex character of
the area, which is characterized by high radioactivity and hydrocarbon generation, could be the result of
several factors, which will be the subject of the following studies.
Georeferencing geogenic gas emissions data base of Romania (WP4)
The collected information from all the areas investigated within the project, are synthesized in an interactive
graphical data base which can be found at the following link:
http://hydrocarbonseepage.blogspot.ro/
This website is synchronized with a similar data base for Italy, which can be found at the following link:
http://hydrocarbonseeps.blogspot.it/
The Romanian database includes also the locations for which only indirect information is available, or obtained
directly by the members of the team through field investigations, and indirectly through literature searches
(fig. 5).
Fig. 5. HYSED‐RO database. The distribution of seeps in Romania
Most of the times, the locations described in the literature are difficult and sometimes impossible to find in
the field. Furthermore, many of them are no more active, consequently the seeps were labelled as certain or
uncertain. The directly identified locations were distributed on the map by using their GPS coordinates.
Fig. 6. The distribution map of seeps in Buzau area, with informations for Fierbatori, near Berca
In the database, the seeps were inventoried as: seeps, mud volcanoes, oil seeps, rich gas springs, and asphalt
pits. Each location has a set of interactive information about the gas manifestation such as: the type of
manifestation, the uncertainty degree, available sets of data, references. One example is from Fierbatori ‐
Berca area which can be observed in fig. 6.
Dissemination activities
The results were presented at conferences and published in scientific journals. A number of three studies were
presented at conferences, several are in progress and a paper is under review. All the contributions
acknowledge the financial support of the Romanian Government through IDEI Program.
Pop Ioan‐Cristian a member of the research team will defend his thesis in December 2014. The subject of the
thesis includes the project objectives.
References:
Baciu, C; Etiope, G; Cuna, S; et al., 2008, Geofluids, 8, 4, 311‐320. Etiope, G; Feyzullayev, A; Baciu, CL, 2009, Marine and Petroleum Geology, 26, 3, 333‐344. Etiope, G; Baciu, C, 2010, Geofluids, 10, 4, 457‐462. Etiope, G; Baciu, CL; Schoell, M., 2011, Chemical Geology, 280, 1‐2, 89‐96. Filipescu M.N., Huma I., 1979, Geochimia gazelor naturale. Editura Academiei R.S.R., Bucuresti. Spulber, L; Etiope, G; Baciu, C; et al., 2010, Geofluids, 10, 4, 463‐475. 26.11.2014
Project responsible,
Prof. Laurentiu‐Calin Baciu