The Composition and Petroleum Generation Characteristics of The Organic Matter in Rocks from Outcrops in The Southern Part of Sakhalin Island (for Stratigraphic Analogs of The Pilskaya Formation)

2021 ◽  
Author(s):  
E.A. Leushina ◽  
A.V. Levin ◽  
E.V. Kozlova ◽  
T. E. Shkutina ◽  
M.Yu. Spasennykh
Keyword(s):  
Organic Matter ◽  
Sakhalin Island ◽  
Petroleum Generation

Pb, Sr, and Nd isotopic features in organic matter from China and their implications for petroleum generation and migration

2001 ◽  
Vol 65 (15) ◽  
pp. 2555-2570 ◽  
Author(s):  
Zhu Bing-Quan ◽  
Zhang Jing-Lian ◽  
Tu Xiang-Lin ◽  
Chang Xiang-Yang ◽  
Fan Cai-Yuan ◽  
...  
Keyword(s):  
Organic Matter ◽  
Petroleum Generation ◽  
And Migration

Multi-proxy study of cannon-ball concretions with glendonites from Paleogene-Neogene sediments of Sakhalin Island: implication for concretion growth and ikaite-calcite trans-formation

2020 ◽  
Author(s):  
Kseniia Vasileva ◽  
Victoria Ershova ◽  
Oleg Vereshchagin ◽  
Mikhail Rogov ◽  
Marianna Tuchkova ◽  
...  
Keyword(s):  
Organic Matter ◽  
Pore Space ◽  
Sakhalin Island ◽  
Burial Diagenesis ◽  
Geochemical Environment ◽  
Low Magnesium ◽  
Carbonate Concretions ◽  
Sediment Formation ◽  
Magnesium Calcite ◽  
High Magnesium Calcite

<p>The objects of the current study are glendonite pseudomorphs forming the central part of cannon-ball carbonate concretions found within Miocene terrigeneous sediments of Sakhalin island (easternmost part of Russia). Twelve samples of glendonites and host carbonate concretions were examined using optical and cathodoluminescence microscopy, EDX analysis, powder X-ray diffraction and isotopic analysis. The aim of the study is to determine the origin of the concretions and the relationships between the concretion and glendonite occurrence.</p><p>Glendonites and host cannon-ball concretions were found within terrigeneous sediments of Bora (Lower Miocene) and Vengeri (Upper Miocene) formations. These formations are composed of laminated sandstones, siltstones, argillites and siliceous rocks. Dropstones are often found within these sediments as well as cannon-ball carbonate concretions, some of them with glendonites in central part. 60-90% of the cannon-ball concretion is occupied by sandy limestone (with high-magnesium calcite) and occasionally contains dolomite and pyrite. Central part of the cannon-ball concretion is occupied by glendonite (single crystal-like or star-like cluster of crystals). Glendonites are composed of several calcite generations. Rosette-like calcite crystals (“ikaite-derived calcite”) are composed of low-magnesium calcite, they are non-luminescent. Needle-like calcite cement is composed of high-magnesium calcite or dolomite and show bright-yellow cathodoluminescence. The rest of the glendonite is occupied with low-magnesium radiaxial fibrous or sparry calcite with dark-red cathodoluminescence.</p><p>Isotopic ratios of glendonites are close to those of host concretions. For host concretions δ<sup>13</sup>С varies from -20.3 to -14.9 ‰PDB, δ<sup>18</sup>О varies from +1.7 to +2.7 ‰PDB; for glendonites δ<sup>13</sup>С varies from -18.1 to -1.9 ‰PDB, while δ<sup>18</sup>О varies from +0.7 to +3.4 ‰PDB.</p><p>Close mineralogical and isotopic composition of the studied glendonites and host cannon-ball concretions suggest they were formed in similar geochemical environment. Association of glendonite occurrence along with dropstones is an indicator of cold conditions, which is well-corresponding with view on glendonites as a proxy for cooling events. Cementation of surrounding sediment (formation of the cannon-ball concretions) and glendonite formation was simultaneous and occurred during early diagenesis in the sulfate-reduction zone. The source of calcium and magnesium ions was seawater (δ<sup>18</sup>О values are characteristic for seawater). Ikaite was replaced with low-magnesium calcite; the replacement was favored by organic matter decay (δ<sup>13</sup>C values are characteristic for organic matter). Cementation of the cannon-ball concretion with high-magnesium calcite occurred together with needle-like high-magnesium calcite growth in the glendonite with increasing concentration of magnesium due to calcite extraction from the pore water. The remaining pore space was subsequently filled with radiaxial fibrous or blocky sparry calcite during burial diagenesis.</p><p>The study is supported by RFBR, project number 20-35-70012.</p>

C-S-Fe geochemistry of some modern and ancient anoxic marine muds and mudstones

1993 ◽  
Vol 344 (1670) ◽  
pp. 89-100 ◽  
Keyword(s):  
Organic Matter ◽  
Molecular Mass ◽  
Low Temperatures ◽  
Early Diagenesis ◽  
Thermal Maturity ◽  
Partial Reduction ◽  
Lower Molecular Mass ◽  
Petroleum Generation ◽  
Bottom Waters ◽  
Pyrite Formation

Most sedimentary C, S and Fe occurs in marine muds and is originally present as an unstable mixture of dissolved sulphate, organic matter and detrital Fe minerals. During early diagenesis, key reactants are either destroyed (reduction of Fe(III) and SO 2- 4 to form pyrite), created (organically bound sulphur (OBS)) or preserved (Fe-bearing silicates). Pyrite formation is commonly limited not by sulphide availability but by the rate at which detrital Fe minerals react with sulphide. At low temperatures, detrital Fe(II) and Fe(III)-bearing clay minerals react very slowly with sulphide and are buried intact. The uptake of sulphur into organic matter is not, as commonly assumed, sulphide-limited. We believe that polysulphides react rapidly with organic matter and that the availability of reactive polysulphides may also influence the sulphur content of kerogen. Polysulphide formation is favoured at stable aerobic-anaerobic interfaces and sediments deposited under weakly oxygenated bottom waters are most likely to contain sulphur-rich kerogen. Deep burial (greater than 70 °C) C-S-Fe diagenesis is characterized by the loss and partial reduction of Fe(III) from smectitic and illitic clays and the conversion of limited amounts of obs to lower molecular mass S compounds. Pyrite formation is volumetrically insignificant. More than 90% of obs remains within organic-rich mudrocks during petroleum generation and expulsion, preserving a sulphur-enriched residual kerogen. The extent to which obs is eventually converted to H 2 S, and at what level of thermal maturity, is unclear. If, as may be likely, much of the sulphur in residual kerogen is thiophenic, it will be stable to at least 200 °C.

scholarly journals Comparative Assessment of Hydrocarbon Generation Potential of Organic Matter from Shale Sediments along Isugwuato – Okigwe Axis, Anambra Basin, SE Nigeria

2021 ◽  
Vol 25 (3) ◽  
pp. 353-362
Author(s):  
M.U. Uzoegbu ◽  
C.U. Ugwueze
Keyword(s):  
Organic Matter ◽  
Oil And Gas ◽  
Oxygen Index ◽  
Hydrocarbon Generation ◽  
Hydrocarbon Generation Potential ◽  
Anambra Basin ◽  
Kerogen Type ◽  
Oil Generation ◽  
Carbonaceous Shales ◽  
Petroleum Generation

TRACT: The Cretaceous sediments in the Anambra Basin (SE Nigeria) consist of a cyclic succession of coals, carbonaceous shales, silty shales and siltstones  interpreted as deltaic deposits. The objective of this study is to compare the hydrocarbon generation potential of organic matter from shale sediments along Isugwuato-Okigwe axis in the Anambra Basin, Nigeria. Data obtained indicates the presence of Type III kerogen with Tmax values are between 424 and 441ºC indicating that the shales are thermally immature to marginally mature with respect to petroleum generation. Hydrogen Index (HI) values range from 14 to 388.9mgHC/gTOC while S1 + S2 yields values ranging from 0.2 to 1.0mgHC/g rock, suggesting that the shale have gas generating potential. The TOC values rangesfrom 1.3 to 3.0%, an indication of a good source rock of terrestrially derived organic matter. The high oxygen index (OI) (16.3 mgCO2g-1TOC), TS (1.35) and TOC/TS (1.5) suggest deposition in a shallow marine environment. Based on the kerogen type, shales from the studied area will equally generate oil and gas if its organic matter attained sufficient thermal temperature. Keywords: Shale, kerogen type, maturity, oil generation.

Organic geochemistry, petrology and palynofacies of Middle Devonian lacustrine flagstones in the Orcadian Basin, Scotland: depositional environment, thermal history and petroleum generation potential

2016 ◽  
Vol 155 (4) ◽  
pp. 773-796 ◽  
Author(s):  
ASSAD GHAZWANI ◽  
RALF LITTKE ◽  
VICTORIA SACHSE ◽  
REINHARD FINK ◽  
NICOLAJ MAHLSTEDT ◽  
...  
Keyword(s):  
Organic Matter ◽  
Middle Devonian ◽  
Depositional Environment ◽  
Organic Geochemistry ◽  
Oil Field ◽  
Source Rocks ◽  
Hydrocarbon Generation ◽  
Petroleum Generation ◽  
Orcadian Basin ◽  
Biomarker Data

AbstractDuring Middle Devonian time a thick succession of organic-rich, mainly lacustrine flagstones developed within the Orcadian Basin. These petroleum source rocks crop out in northern Scotland. Nineteen samples were studied using organic petrology, palynology and organic geochemistry in order to characterize kerogen type, depositional environment, thermal maturity and petroleum generation potential. Corg, carbonate and sulphur content as well as hydrogen index (HI) values are quite variable (e.g. HI from 79 to 744 mg HC/g Corg). Based on biomarker data, organic material mainly originates from aquatic organic matter deposited under lacustrine conditions with oxygen-depleted, but not permanently anoxic, bottom waters. Petrography reveals small quantities of vitrinite particles, indicating minor input of terrestrial material. This is supported by biomarker data and the palynofacies, which is characterized by a high amount of oil-prone amorphous organic matter (AOM) and generally few miospores. Maturity of the succession studied in Caithness and Orkney is between immature and oil mature. One-dimensional basin modelling shows that a significant remaining hydrocarbon generation potential exists within the Middle Devonian succession. In contrast to the low hydrocarbon generation in the onshore area, offshore oil generation was significant, especially after deposition of thick Upper Jurassic – Upper Cretaceous sediments. At the end of Cretaceous time, hydrocarbon generation ceased due to uplift. The contribution to known oil fields from the Devonian flagstones is a realistic scenario, including a contribution to the Beatrice oil field in the south of the modelled area.

scholarly journals GEOCHEMISTRY OF MINERAL WATERS AND HYDROGENIC SEDIMENTS OF THE ANTONOV HYDROSULPHURIC MINERAL SPRING, SAKHALIN ISLAND

2020 ◽  
Vol 39 (6) ◽  
pp. 98-113
Author(s):  
G.A. Chelnokov ◽  
◽  
I.V. Bragin ◽  
I.A. Kharitonova ◽  
K.Yu. Bushkareva ◽  
...  
Keyword(s):  
Organic Matter ◽  
Hydrogen Sulfide ◽  
Surface Waters ◽  
Sakhalin Island ◽  
Mineral Waters ◽  
Physical Parameters ◽  
Sulphide Mineral ◽  
Time Data ◽  
Mineral Spring ◽  
Hydrogeological Characteristics

Original data on the isotopic and chemical composition of mineral waters, cold ground and surface waters, as well as hydrogenic deposits of the Antonovsky manifestation of hydrogen sulfide mineral waters (the coast of the Tatar Strait, Sakhalin Island) are provided in the article. For the first time, data on the content of oxygen and hydrogen isotopes in groundwaters and surface waters, the volumetric activity of radon and the rare-earth elements as well were obtained. Based on automatic monitoring of the physical parameters of the waters, their hydrogeological characteristics were determined and balneological properties were assessed. It has been determined that the mineral waters of the spring are weakly alkaline, hydrocarbonate-chloride calcium-sodium, with TDS of up to 1 g/l. According to isotope data, the genesis of waters is atmospheric, and the circulation time is less than 60 years. The gas composition is dominated by nitrogen of atmospheric genesis (δ15N = 0.0). High contents of organic carbon (Corg. = 56.6 mg/l) are explained by the processes of interaction of groundwaters with organic matter of water-bearing rocks. When organic matter decomposes in the presence of sulfates and without oxygen, hydrogen sulfide is released, giving rise to a number of intermediate and stable sulfur compounds in hydrogenic sediments and bacterial mats. Elemental, sulfide and sulfate forms of sulfur have been determined in the bottom sediments as well as new formations of the mineral spring, using electron microscopy. The interaction of waters with organic matter of rocks plays a significant role in the formation of the elemental composition of hydrogenic and biogenic deposits of the Antonovsky hydrogen sulphide mineral spring and their enrichment with such metals as Zn, Ge, As, Sr, Ba, U, and Th as well. A characteristic feature of mineral waters is the presence of a pronounced positive europium anomaly, which is typical for waters with low Eh values.

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