scholarly journals Diamondoids and thiadiamondoids generated from hydrothermal pyrolysis of crude oil and TSR experiments

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Yanyan Peng ◽  
Chunfang Cai ◽  
Chenchen Fang ◽  
Liangliang Wu ◽  
Jinzhong Liu ◽  
...  
Keyword(s):  
Organic Matter ◽  
Crude Oil ◽  
Elevated Temperatures ◽  
Source Rocks ◽  
Natural Conditions ◽  
Chemical Alteration ◽  
Direct Reactions ◽  
New Generation ◽  
Oil Cracking ◽  
New Formula

AbstractDiamondoid compounds are widely used to reflect thermal maturation of high mature source rocks or oils and oil cracking extents. However, diamondoids and thiadiamondoids were demonstrated to have newly been generated and decomposed in our hydrothermal pyrolysis of crude oil and TSR experiments. Our results show that adamantanes and diamantanes are generated primarily within the maturity range 0.48–2.1% and 1.2–3.0% EasyRo, respectively. Their formation is enhanced and the decomposition of diamantanes obviously lags at elevated temperatures compared with anhydrous experiments. MDI, EAI, DMAI-1, DMDI-2 may serve as reliable maturity proxies at > ca.1.0% EasyRo, and other isomerization indices (TMAI-1, TMAI-2 and DMAI-2) are effective for the highly mature organic matter at EasyRo > 2.0%. The extent of oil cracking (EOC) calculated from the broadly used (3- + 4-) MD method (Dahl et al. in Nature 399:54–56, 1999) is proven to overestimate, especially for highly cracked samples due to the new generation of (3- + 4-) MD. Still, it can be corrected using a new formula at < 3.0% EasyRo. Other diamondoid-related indices (e.g., EAI, DMDI-2, As/Ds, MAs/MDs, DMAs/DMDs, and DMAs/MDs) can also be used to estimate EOC. However, these indices cannot be applied to TSR-altered petroleum. TSR is experimentally confirmed to generate diamantanes and thiaadmantanes at 1.81% EasyRo likely via direct reactions of reduced S species with hydrocarbons and accelerate the decomposition of diamantanes at > 2.62% EasyRo compared with thermal chemical alteration (TCA). More studies are needed to assess specific mechanisms for the formation of thiadiamondoids under natural conditions.

scholarly journals Diamondoids and Thiadiamondoids Generated From Hydrothermal Pyrolysis of Crude Oil and TSR Experiments

2021 ◽  
Author(s):  
Yanyan Peng ◽  
Chunfang Cai ◽  
Chenchen Fang ◽  
Liangliang Wu ◽  
Jinzhong Liu ◽  
...  
Keyword(s):  
Organic Matter ◽  
Crude Oil ◽  
Elevated Temperatures ◽  
Source Rocks ◽  
Chemical Alteration ◽  
Thermal Maturation ◽  
Direct Reactions ◽  
New Generation ◽  
Oil Cracking ◽  
New Formula

Abstract Diamondoid compounds are widely used to reflect thermal maturation of high mature source rocks or oils and oil cracking extents. However, diamondoids and thiadiamondoids were demonstrated to have newly been generated and decomposed in our hydrothermal pyrolysis of crude oil and TSR experiments. Our results show that adamantanes and diamantanes are generated primarily within the maturity range 0.48–2.1% and 1.2–3.0% EasyRo, respectively. Their formation is enhanced and the decomposition of diamantanes obviously lags behind at elevated temperatures compared with anhydrous experiments. MDI, EAI, DMAI-1, DMDI-2 may serve as reliable maturity proxies at > ca.1.0% EasyRo, and other isomerization indices (TMAI-1, TMAI-2 and DMAI-2) are effective for the highly mature organic matter at EasyRo > 2.0%. The extent of oil cracking (EOC) calculated from the broadly used 3-+4-MD method (Dahl et al., 1999) is proven to overestimate, especially for highly cracked samples due to the new generation of 3-+4-MD. Still, it can be corrected using a new formula at <3.0% EasyRo. Other diamondoid-related indices (e.g. EAI, DMDI-2, As/Ds, MAs/MDs, DMAs/DMDs, and DMAs/MDs) can also be used to estimate EOC. However, these indices cannot be applied to TSR-altered petroleum. TSR is experimentally confirmed to generate diamantanes and thiaadmantanes at 1.81% EasyRo via direct reactions of reduced S species with hydrocarbons and accelerate the decomposition of diamantanes at > 3.0% EasyRo compared with thermal chemical alteration (TCA).

Oil–source rock correlation for tight oil in tuffaceous reservoirs in the Permian Tiaohu Formation, Santanghu Basin, northwest China

2015 ◽  
Vol 52 (11) ◽  
pp. 1014-1026 ◽  
Author(s):  
Jian Ma ◽  
Zhilong Huang ◽  
Xiaoyu Gao ◽  
Changchao Chen
Keyword(s):  
Organic Matter ◽  
Crude Oil ◽  
Source Rock ◽  
Stable Carbon Isotope ◽  
Northwest China ◽  
Source Rocks ◽  
Tight Oil ◽  
Stable Carbon ◽  
Lucaogou Formation ◽  
Oil Source

Tight oil in the Permian Tiaohu Formation in the Santanghu Basin, northwest China, has a peculiar property such that the reservoir is sedimentary organic matter-bearing tuff characterized by high porosity (10%–25%) and very low permeability, mainly in the range of 0.01–0.50 mD. Biomarker and stable carbon isotope compositions of selected crude oils and source-rock extracts were analyzed to determine the source rock of the tight oil. Source rocks in the Lucaogou Formation consist of various rock types dominated by mudstones containing organic matter with intense yellow–green fluorescence. Mudstones in the Lucaogou Formation have total organic carbon (TOC) values mainly in the range of 1.0–8.0 wt%, hydrocarbon generation potential (S1 + S2) mostly >6 mg/g, and chloroform extractable bitumen “A” generally >0.1%. The maceral composition is predominantly fluorescing amorphinite. The hydrogen index (HI) varies from 300 to 900 mg HC/g TOC, indicating dominant Type I and Type II kerogen. Compared with the mudstones and tuffs in the Tiaohu Formation, the mudstones in the Lucaogou Formation are the best source rocks. The biomarker characteristics of mudstone extracts in the Lucaogou Formation differ from those in the Tiaohu Formation, based on the gammacerane index, β-carotane content, and the relative contents of C27, C28, and C29 regular steranes. Crude oil samples in the tuff show low pristane/phytane (Pr/Ph) ratios, high gammacerane indices, high β-carotane, and a dominance of the C29 regular sterane followed by C28 and C27 steranes, as well as depleted stable carbon isotope compositions. Oil–source correlation with biomarkers and δ13C values shows that the crude oil in the tuffs mainly originates from underlying source rocks in the Lucaogou Formation. The sedimentary organic matter in the tuffs also makes a small contribution to the tuffaceous reservoir. Therefore, the tuffaceous tight reservoir in the Tiaohu Formation is unusual in that the oil is not indigenous; rather, it migrates a long distance to accumulate in the upper reservoir.

scholarly journals Effective source rock selection and oil–source correlation in the Western Slope of the northern Songliao Basin, China

2021 ◽  
Vol 18 (2) ◽  
pp. 398-415
Author(s):  
He Bi ◽  
Peng Li ◽  
Yun Jiang ◽  
Jing-Jing Fan ◽  
Xiao-Yue Chen
Keyword(s):  
Organic Matter ◽  
Source Rock ◽  
Thermal Evolution ◽  
Songliao Basin ◽  
Source Rocks ◽  
Crude Oils ◽  
Western Slope ◽  
Geochemical Parameters ◽  
Group I ◽  
Oil Source

AbstractThis study considers the Upper Cretaceous Qingshankou Formation, Yaojia Formation, and the first member of the Nenjiang Formation in the Western Slope of the northern Songliao Basin. Dark mudstone with high abundances of organic matter of Gulong and Qijia sags are considered to be significant source rocks in the study area. To evaluate their development characteristics, differences and effectiveness, geochemical parameters are analyzed. One-dimensional basin modeling and hydrocarbon evolution are also applied to discuss the effectiveness of source rocks. Through the biomarker characteristics, the source–source, oil–oil, and oil–source correlations are assessed and the sources of crude oils in different rock units are determined. Based on the results, Gulong and Qijia source rocks have different organic matter primarily detrived from mixed sources and plankton, respectively. Gulong source rock has higher thermal evolution degree than Qijia source rock. The biomarker parameters of the source rocks are compared with 31 crude oil samples. The studied crude oils can be divided into two groups. The oil–source correlations show that group I oils from Qing II–III, Yao I, and Yao II–III members were probably derived from Gulong source rock and that only group II oils from Nen I member were derived from Qijia source rock.

scholarly journals The influences of sedimentary environments on organic matter enrichment in fine-grained rocks of the Paleogene Shahejie formation in Nanpu Sag, Huanghua Depression, Bohai Bay Basin

2021 ◽  
pp. 014459872110310
Author(s):  
Min Li ◽  
Xiongqi Pang ◽  
Guoyong Liu ◽  
Di Chen ◽  
Lingjian Meng ◽  
...  
Keyword(s):  
Organic Matter ◽  
Source Rocks ◽  
Bohai Bay ◽  
Bohai Bay Basin ◽  
Humid Climate ◽  
High Productivity ◽  
Fine Grained ◽  
Huanghua Depression ◽  
Shahejie Formation ◽  
Nanpu Sag

The fine-grained rocks in the Paleogene Shahejie Formation in Nanpu Sag, Huanghua Depression, Bohai Bay Basin, are extremely important source rocks. These Paleogene rocks are mainly subdivided into organic-rich black shale and gray mudstone. The average total organic carbon contents of the shale and mudstone are 11.5 wt.% and 8.4 wt.%, respectively. The average hydrocarbon (HC)-generating potentials (which is equal to the sum of free hydrocarbons (S1) and potential hydrocarbons (S2)) of the shale and mudstone are 39.3 mg HC/g rock and 28.5 mg HC/g rock, respectively, with mean vitrinite reflectance values of 0.82% and 0.81%, respectively. The higher abundance of organic matter in the shale than in the mudstone is due mainly to paleoenvironmental differences. The chemical index of alteration values and Na/Al ratios reveal a warm and humid climate during shale deposition and a cold and dry climate during mudstone deposition. The biologically derived Ba and Ba/Al ratios indicate high productivity in both the shale and mudstone, with relatively low productivity in the shale. The shale formed in fresh to brackish water, whereas the mudstone was deposited in fresh water, with the former having a higher salinity. Compared with the shale, the mudstone underwent higher detrital input, exhibiting higher Si/Al and Ti/Al ratios. Shale deposition was more dysoxic than mudstone deposition. The organic matter enrichment of the shale sediments was controlled mainly by reducing conditions followed by moderate-to-high productivity, which was promoted by a warm and humid climate and salinity stratification. The organic matter enrichment of the mudstone was less than that of the shale and was controlled by relatively oxic conditions.

Elevated temperatures drive abiotic and biotic degradation of organic matter in a peat bog under oxic conditions

2022 ◽  
Vol 804 ◽  
pp. 150045
Author(s):  
Roya AminiTabrizi ◽  
Katerina Dontsova ◽  
Nathalia Graf Grachet ◽  
Malak M. Tfaily
Keyword(s):  
Organic Matter ◽  
Elevated Temperatures ◽  
Peat Bog ◽  
Biotic Degradation

scholarly journals Low Temperature Illitization through Illite-Dioctahedral Vermiculite Mixed Layers in a Tropical Saline Lake Rich in Hydrothermal Fluids (Sochagota Lake, Colombia)

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 523
Author(s):  
Gabriel Ricardo Cifuentes ◽  
Juan Jiménez-Millán ◽  
Claudia Patricia Quevedo ◽  
Fernando Nieto ◽  
Javier Cuadros ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Organic Matter ◽  
Low Temperature ◽  
High Salinity ◽  
Source Rocks ◽  
Temperate Climate ◽  
Lake Basin ◽  
X Ray ◽  
Saline Waters ◽  
Mixed Layers

In this investigation, we showed that high salinity promoted by hydrothermal inputs, reducing conditions of sediments with high content in organic matter, and the occurrence of an appropriate clay mineral precursor provide a suitable framework for low-temperature illitization processes. We studied the sedimentary illitization process that occurs in carbonaceous sediments from a lake with saline waters (Sochagota Lake, Colombia) located at a tropical latitude. Water isotopic composition suggests that high salinity was produced by hydrothermal contribution. Materials accumulated in the Sochagota Lake’s southern entrance are organic matter-poor sediments that contain detrital kaolinite and quartz. On the other hand, materials formed at the central segment and near the lake exit (north portion) are enriched in organic matter and characterized by the crystallization of Fe-sulfides. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), and energy dispersive X-ray spectrometry (EDX) data allowed for the identification of illite and illite-dioctahedral vermiculite mixed layers (I-DV), which are absent in the southern sediments. High humidity and temperate climate caused the formation of small-sized metastable intermediates of I-DV particles by the weathering of the source rocks in the Sochagota Lake Basin. These particles were deposited in the low-energy lake environments (middle and north part). The interaction of these sediments enriched in organic matter with the saline waters of the lake enriched in hydrothermal K caused a reducing environment that favored Fe mobilization processes and its incorporation to I-DV mixed layers that acted as mineral precursor for fast low temperature illitization, revealing that in geothermal areas clays in lakes favor a hydrothermal K uptake.

Compositional Characteristics and Geochemical Significance of N-alkanes in Process of Crude Oil Cracking

2009 ◽  
Vol 16 (6) ◽  
pp. 372-378 ◽  
Author(s):  
Xiaoqiang TANG ◽  
Guanghui HUANG ◽  
Min ZHANG ◽  
Jinping HAN
Keyword(s):  
Crude Oil ◽  
Geochemical Significance ◽  
Oil Cracking

XD™ Titanium Aluminide Composites

1988 ◽  
Vol 120 ◽  
Author(s):  
L. Christodoulou ◽  
P. A. Parrish ◽  
C. R. Crowe
Keyword(s):  
Titanium Aluminide ◽  
Elevated Temperatures ◽  
Coefficient Of Thermal Expansion ◽  
Measurement Techniques ◽  
Physical Property ◽  
Casting Process ◽  
Matrix Composition ◽  
Al Alloy ◽  
Matrix Composites ◽  
New Generation

AbstractThe advantages of reinforcing metals with ceramic particles to produce metal matrix composites are well known. The behavior of discontinuously reinforced intermetallic compounds, however, has not been extensively studied. Martin Marietta Laboratories has produced a new generation of discontinuously reinforced titanium aluminide composites using a proprietary casting process known as XD™ technology. These new materials possess enhanced properties at room and elevated temperatures and may be cast, extruded, or forged. The effects of matrix composition, reinforcing phase, and thermal mechanical processing on properties have been studied using optical and various electron microscopy and mechanical and physical property measurement techniques to characterize the alloys. To date, most work has been done on a two-phased lamellar Ti-45 a/o Al alloy reinforced with TiB2 ceramic having an equiaxed morphology. Data on temperature dependence of the dynamic Young's modulus, coefficient of thermal expansion, deformation and fracture behavior, and microstructure are presented.

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