Geochemical characteristics and mechanisms of densification of pre-Jurassic crude oil in the Tainan Sag, Turpan-Hami Basin, China

Large volumes of heavy oil were distributed in the pre-Jurassic strata of Tainan sag, Turpan Hami Basin, China. The geochemical characteristics and origins of heavy oil are of great significance to future exploration in the region. This study classified crude oil using data on its physical propertie...

Popoln opis

Bibliografske podrobnosti
Main Authors: Yaao Chi, Bo Liu, Yuchu Chen, Boyang Wang, Longhui Bai, Liu Wang, Yaohui Xu
Format: Article
Jezik:English
Izdano: KeAi Communications Co., Ltd. 2022-01-01
Serija:Unconventional Resources
Teme:
Online dostop:http://www.sciencedirect.com/science/article/pii/S2666519022000206
_version_ 1827980644132585472
author Yaao Chi
Bo Liu
Yuchu Chen
Boyang Wang
Longhui Bai
Liu Wang
Yaohui Xu
author_facet Yaao Chi
Bo Liu
Yuchu Chen
Boyang Wang
Longhui Bai
Liu Wang
Yaohui Xu
author_sort Yaao Chi
collection DOAJ
description Large volumes of heavy oil were distributed in the pre-Jurassic strata of Tainan sag, Turpan Hami Basin, China. The geochemical characteristics and origins of heavy oil are of great significance to future exploration in the region. This study classified crude oil using data on its physical properties, group composition, and biomarker compounds. Further, the distribution of different types of crude oil in lateral and vertical directions are clarified. Mechanism of densification of crude oil in the study area was aslo summarized. Results indicate that there are four categories of crude oil with different densities in the Tainan Sag, which are distributed across the areas of (from west to east) Tuyuke, Lukeqin, and Yingyeer: light oil (<0.9/cm3), heavy oil (0.9–0.93 g/cm3), extra-heavy oil (0.93–0.98 g/cm3), and ultra-heavy oil (>0.98 g/cm3). Notable differences were observed in the composition of these distinct crude oil types. As the densification degree of crude oil increases, the content of saturated hydrocarbon and aromatic hydrocarbon decreases gradually, and the content of asphaltene increases gradually. The light oil in the Tuyuke area of the Tainan Sag has undergone severe water washing and slight-to-moderate biodegradation. The extra-heavy oil in the Lukeqin area has undergone severe water washing but moderate-to-severe biodegradation. The ultra-heavy oil in the Yingyeer area has not undergone notable water washing but has been subjected to severe biodegradation. Biodegradation damages saturated hydrocarbons and aromatic hydrocarbons in crude oil to varying degrees, increasing the relative content of non-hydrocarbon constituents and asphaltenes and causing the oil to thicken gradually. This occurrence is highly common in areas of severe strata erosion. Water washing, usually occurring in the interlayers where oil and water are in contact with each other over a large area, causes densification of the oil by destroying the low-carbon aromatics in it. This study determined the geochemical characteristics, as well as the reservoir geology of crude oil under various causes of densification and, can serve as a scientific reference for research on the mechanisms of densification of crude oil in other locations.
first_indexed 2024-04-09T21:56:45Z
format Article
id doaj.art-c2d7574711ca46b8a2e94e99b51cf9b1
institution Directory Open Access Journal
issn 2666-5190
language English
last_indexed 2024-04-09T21:56:45Z
publishDate 2022-01-01
publisher KeAi Communications Co., Ltd.
record_format Article
series Unconventional Resources
spelling doaj.art-c2d7574711ca46b8a2e94e99b51cf9b12023-03-24T04:23:29ZengKeAi Communications Co., Ltd.Unconventional Resources2666-51902022-01-012183191Geochemical characteristics and mechanisms of densification of pre-Jurassic crude oil in the Tainan Sag, Turpan-Hami Basin, ChinaYaao Chi0Bo Liu1Yuchu Chen2Boyang Wang3Longhui Bai4Liu Wang5Yaohui Xu6Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development, Ministry of Education, Northeast Petroleum University, Daqing, 163318, ChinaKey Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development, Ministry of Education, Northeast Petroleum University, Daqing, 163318, China; Hubei Key Laboratory of Petroleum Geochemistry and Environment, Yangtze University, Wuhan, 430100, China; Corresponding author. Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development, Ministry of Education, Northeast Petroleum University, Daqing, 163318, China.Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development, Ministry of Education, Northeast Petroleum University, Daqing, 163318, China; College of Earth Sciences, Northeast Petroleum University, Daqing, 163318, ChinaKey Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development, Ministry of Education, Northeast Petroleum University, Daqing, 163318, ChinaKey Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development, Ministry of Education, Northeast Petroleum University, Daqing, 163318, ChinaKey Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development, Ministry of Education, Northeast Petroleum University, Daqing, 163318, ChinaHubei Key Laboratory of Petroleum Geochemistry and Environment, Yangtze University, Wuhan, 430100, ChinaLarge volumes of heavy oil were distributed in the pre-Jurassic strata of Tainan sag, Turpan Hami Basin, China. The geochemical characteristics and origins of heavy oil are of great significance to future exploration in the region. This study classified crude oil using data on its physical properties, group composition, and biomarker compounds. Further, the distribution of different types of crude oil in lateral and vertical directions are clarified. Mechanism of densification of crude oil in the study area was aslo summarized. Results indicate that there are four categories of crude oil with different densities in the Tainan Sag, which are distributed across the areas of (from west to east) Tuyuke, Lukeqin, and Yingyeer: light oil (<0.9/cm3), heavy oil (0.9–0.93 g/cm3), extra-heavy oil (0.93–0.98 g/cm3), and ultra-heavy oil (>0.98 g/cm3). Notable differences were observed in the composition of these distinct crude oil types. As the densification degree of crude oil increases, the content of saturated hydrocarbon and aromatic hydrocarbon decreases gradually, and the content of asphaltene increases gradually. The light oil in the Tuyuke area of the Tainan Sag has undergone severe water washing and slight-to-moderate biodegradation. The extra-heavy oil in the Lukeqin area has undergone severe water washing but moderate-to-severe biodegradation. The ultra-heavy oil in the Yingyeer area has not undergone notable water washing but has been subjected to severe biodegradation. Biodegradation damages saturated hydrocarbons and aromatic hydrocarbons in crude oil to varying degrees, increasing the relative content of non-hydrocarbon constituents and asphaltenes and causing the oil to thicken gradually. This occurrence is highly common in areas of severe strata erosion. Water washing, usually occurring in the interlayers where oil and water are in contact with each other over a large area, causes densification of the oil by destroying the low-carbon aromatics in it. This study determined the geochemical characteristics, as well as the reservoir geology of crude oil under various causes of densification and, can serve as a scientific reference for research on the mechanisms of densification of crude oil in other locations.http://www.sciencedirect.com/science/article/pii/S2666519022000206Turpan-Hami BasinTainan SagHeavy oilDensification mechanismBiodegradationWater washing
spellingShingle Yaao Chi
Bo Liu
Yuchu Chen
Boyang Wang
Longhui Bai
Liu Wang
Yaohui Xu
Geochemical characteristics and mechanisms of densification of pre-Jurassic crude oil in the Tainan Sag, Turpan-Hami Basin, China
Unconventional Resources
Turpan-Hami Basin
Tainan Sag
Heavy oil
Densification mechanism
Biodegradation
Water washing
title Geochemical characteristics and mechanisms of densification of pre-Jurassic crude oil in the Tainan Sag, Turpan-Hami Basin, China
title_full Geochemical characteristics and mechanisms of densification of pre-Jurassic crude oil in the Tainan Sag, Turpan-Hami Basin, China
title_fullStr Geochemical characteristics and mechanisms of densification of pre-Jurassic crude oil in the Tainan Sag, Turpan-Hami Basin, China
title_full_unstemmed Geochemical characteristics and mechanisms of densification of pre-Jurassic crude oil in the Tainan Sag, Turpan-Hami Basin, China
title_short Geochemical characteristics and mechanisms of densification of pre-Jurassic crude oil in the Tainan Sag, Turpan-Hami Basin, China
title_sort geochemical characteristics and mechanisms of densification of pre jurassic crude oil in the tainan sag turpan hami basin china
topic Turpan-Hami Basin
Tainan Sag
Heavy oil
Densification mechanism
Biodegradation
Water washing
url http://www.sciencedirect.com/science/article/pii/S2666519022000206
work_keys_str_mv AT yaaochi geochemicalcharacteristicsandmechanismsofdensificationofprejurassiccrudeoilinthetainansagturpanhamibasinchina
AT boliu geochemicalcharacteristicsandmechanismsofdensificationofprejurassiccrudeoilinthetainansagturpanhamibasinchina
AT yuchuchen geochemicalcharacteristicsandmechanismsofdensificationofprejurassiccrudeoilinthetainansagturpanhamibasinchina
AT boyangwang geochemicalcharacteristicsandmechanismsofdensificationofprejurassiccrudeoilinthetainansagturpanhamibasinchina
AT longhuibai geochemicalcharacteristicsandmechanismsofdensificationofprejurassiccrudeoilinthetainansagturpanhamibasinchina
AT liuwang geochemicalcharacteristicsandmechanismsofdensificationofprejurassiccrudeoilinthetainansagturpanhamibasinchina
AT yaohuixu geochemicalcharacteristicsandmechanismsofdensificationofprejurassiccrudeoilinthetainansagturpanhamibasinchina