Source rock with high abundance of C28 regular sterane in typical brackish-saline lacustrine sediments: Biogenic source, depositional environment and hydrocarbon generation potential in Junggar Basin, China

2021 ◽  
pp. 109670
Author(s):  
Shiju Liu ◽  
Gang Gao ◽  
Jun Jin ◽  
Wenzhe Gang ◽  
Baoli Xiang
Keyword(s):  
Source Rock ◽  
Depositional Environment ◽  
Lacustrine Sediments ◽  
Junggar Basin ◽  
High Abundance ◽  
Hydrocarbon Generation ◽  
Hydrocarbon Generation Potential ◽  
Saline Lacustrine ◽  
Biogenic Source

scholarly journals Revisiting Controls on Shale Oil Accumulation in Saline Lacustrine Basins: The Permian Lucaogou Formation Mixed Rocks, Junggar Basin

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-25
Author(s):  
Chenjia Zhang ◽  
Jian Cao ◽  
Erting Li ◽  
Yuce Wang ◽  
Wenyao Xiao ◽  
...  
Keyword(s):  
Carbonate Rocks ◽  
Junggar Basin ◽  
Type I ◽  
Hydrocarbon Generation ◽  
Shale Oil ◽  
Oil Accumulation ◽  
Hydrocarbon Generation Potential ◽  
Lucaogou Formation ◽  
Saline Lacustrine ◽  
Lacustrine Basins

Fine-grained mixed rocks in saline lacustrine basins are important targets for shale oil exploration. However, the controls on shale oil accumulation are complex due to the multi-source mixed deposition. This is a challenging issue in the study of shale oil. Here, we present a case study in the Middle Permian Lucaogou Formation in the Jimusar Sag, Junggar Basin, northwestern China. Results show that the Lucaogou Formation consists mainly of carbonate rocks, dolomitic or calcareous mudstones, tuffaceous or silty mudstones, and siltstones. The dolomitic/calcareous mudstones ( TO C average = 6.44   wt . % ) and tuffaceous/silty mudstones ( TO C average = 4.83   wt . % ) have the best hydrocarbon generation potential and contain type I–II1 kerogens that are in the peak oil generation stage. However, the shale oil potential is highest for the carbonate rocks and siltstones with average oil saturation index (OSI) values of 315.03 mg HC/g TOC and 343.27 mg HC/g TOC, respectively. This indicates that hydrocarbon generation potential is not the main factor controlling shale oil potential. Micro-nanoscale pores are the main control. Abundant dissolution pores provide excellent reservoir space for near-source migration and accumulation of shale oil. Different mixing processes between lithofacies control the accumulation of shale oil, and shale oil productivity is the best when multi-facies deposition in transitional zones formed the mixed rocks (facies mixing). In addition, local accumulations of calcareous organisms and adjacent carbonate components on terrigenous sediments (in situ mixing) are also conducive to shale oil enrichment. This is an unusual and special feature of saline lacustrine shale oils, which is different from freshwater lacustrine and marine shale oils. Comprehensive assessment of source rock and reservoir is needed to robustly establish a widely applicable method to determine the shale oil potential in such basins.

Source rock evaluation and hydrocarbon generation potential of Mid-Late Cretaceous sediments from Mintaq-01 well in the Wadi Hajar of Southern Sabatayn Basin, Yemen

2019 ◽  
Vol 38 (3) ◽  
pp. 216-224
Author(s):  
Mohammed Hail Hakimi ◽  
Wan Hasiah Abdullah ◽  
Hussain J. Al Faifi ◽  
Khairul Azlan Mustapha ◽  
Ali Y. Kahal ◽  
...  
Keyword(s):  
Source Rock ◽  
Late Cretaceous ◽  
Hydrocarbon Generation ◽  
Hydrocarbon Generation Potential ◽  
Source Rock Evaluation

High abundance of carotanes in the brackish-saline lacustrine sediments: A possible cyanobacteria source?

2020 ◽  
Vol 219 ◽  
pp. 103373 ◽  
Author(s):  
Wenjing Ding ◽  
Dujie Hou ◽  
Lian Jiang ◽  
Yuhan Jiang ◽  
Piao Wu
Keyword(s):  
Lacustrine Sediments ◽  
High Abundance ◽  
Saline Lacustrine

scholarly journals Geochemical characterization and possible hydrocarbon contribution of the Carboniferous interval natively developed in the Chepaizi Uplift of Junggar Basin, northwestern China

2019 ◽  
Vol 38 (3) ◽  
pp. 654-681 ◽  
Author(s):  
Lixin Mao ◽  
Xiangchun Chang ◽  
Youde Xu ◽  
Bingbing Shi ◽  
Dengkuan Gao
Keyword(s):  
Organic Carbon ◽  
Total Organic Carbon ◽  
Junggar Basin ◽  
Source Rocks ◽  
Hydrocarbon Generation ◽  
Exploration Process ◽  
Potential Source ◽  
Hydrocarbon Generation Potential ◽  
Northwestern Region ◽  
Effective Source

Previous studies on Chepaizi Uplift mainly focused on its reservoirs, and the potential source rocks natively occurred was ignored. During the exploration process, dark mudstones and tuffaceous mudstones were found in the Carboniferous interval. These possible source rocks have caused great concern about whether they have hydrocarbon generation potential and can contribute to the reservoirs of the Chepaizi Uplift. In this paper, the potential source rocks are not only evaluated by the organic richness, type, maturity, and depositional environment, but also divided into different kinetics groups. The Carboniferous mudstones dominated by Type III kerogen were evolved into the stage of mature. Biomarkers indicate that the source rocks were deposited in a marine environment under weakly reducing conditions and received mixed aquatic and terrigenous organic matter, with the latter being predominant. The effective source rocks are characterized by the total organic carbon values >0.5 wt.% and the buried depth >1500 m. The tuffaceous mudstone shows a greater potential for its lower active energy and longer hydrocarbon generation time. Considering the hydrocarbon generation potential, base limits of the total organic carbon and positive correlation of oil–source rock together, the native Carboniferous mudstones and tuffaceous mudstones might contribute to the Chepaizi Uplift reservoirs of the northwestern region of the Junggar Basin, especially the deeper effective source rocks should be paid enough attention to.

HYDROCARBON GENERATION POTENTIAL AND DEPOSITIONAL ENVIRONMENT OF SHALES IN THE CRETACEOUS NAPO FORMATION, EASTERN ORIENTE BASIN, ECUADOR

2017 ◽  
Vol 40 (2) ◽  
pp. 173-193 ◽  
Author(s):  
Xiao-Fa Yang ◽  
Yin-Fu Xie ◽  
Zhi-Wei Zhang ◽  
Zhong-Zhen Ma ◽  
Yu-Bing Zhou ◽  
...  
Keyword(s):  
Depositional Environment ◽  
Hydrocarbon Generation ◽  
Hydrocarbon Generation Potential

scholarly journals Integration of the outcrop and subsurface geochemical data: implications for the hydrocarbon source rock evaluation in the Lower Indus Basin, Pakistan

2018 ◽  
Vol 9 (2) ◽  
pp. 937-951 ◽  
Author(s):  
Sajjad Ahmad ◽  
Faizan Ahmad ◽  
Abd Ullah ◽  
Muhammad Eisa ◽  
Farman Ullah ◽  
...  
Keyword(s):  
Organic Matter ◽  
Source Rock ◽  
Vitrinite Reflectance ◽  
Indus Basin ◽  
Hydrocarbon Generation ◽  
Type Ii ◽  
Hydrocarbon Source Rock ◽  
Hydrocarbon Generation Potential ◽  
Well Data

Abstract The present study details the hydrocarbon source rock geochemistry and organic petrography of the outcrop and subsurface samples of the Middle Jurassic Chiltan Formation and the Lower Cretaceous Sembar Formation from the Sann #1 well Central and Southern Indus Basin, Pakistan. The total organic carbon (TOC), Rock–Eval pyrolysis, vitrinite reflectance (Ro) % and Maceral analysis techniques were used and various geochemical plots were constructed to know the quality of source rock, type of kerogen, level of maturity and migration history of the hydrocarbons. The outcrop and Sann #1 well data on the Sembar Formation reveals poor, fair, good and very good quality of the TOC, type II–III kerogen, immature–mature organic matter and an indigenous hydrocarbon generation potential. The outcrop and Sann #1 well data on the Chiltan Formation show a poor–good quality of TOC, type II–III kerogen, immature–mature source rock quality and having an indigenous hydrocarbon generation potential. The vitrinite reflectance [Ro (%)] values and Maceral types [fluorescent amorphous organic matter, exinite, alginite and inertnite] demonstrate that maturity in both Sembar and the Chiltan formation at surface and subsurface fall in the oil and gas generation zone to cracking of oil to gas condensate zone. Recurrence of organic rich and poor intervals within the Sembar and Chiltan formation are controlled by the Late Jurassic thermal uplift preceding the Indo-Madagascar separation from the Afro-Arabian Plate and Early Cretaceous local transgressive–regressive cycles. From the current study, it is concluded that both Sembar and Chiltan formation can act as a potential hydrocarbon source rock in the study area.

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