the Ministry of Natural Resources has approved the first-phase proven geological reserves jointly submitted by Sinopec Exploration Company and Jianghan Oilfield for the Middle Jurassic Lianggaoshan Formation in Fuxing area
including 2 010.06×10
4
tons of crude oil and 123.52×10
8
m
3
of natural gas. This marks the emergence of Fuxing oilfield
the first shale oilfield in Sich
uan Basin. To further advance the geological theory of terrestrial shale oil and gas accumulation
as well as key exploration technologies
this study systematically analyzes the geological characteristics of terrestrial shale oil and gas in the Jurassic Lianggaoshan Formation based on exploration practices in Fuxing oilfield. The study identifies the main controlling factors for the enrichment and high productivity of shale oil and gas
and proposes key exploration technologies tailored to terrestrial shale oil and gas. Research findings indicate that the upper oil-bearing shale in the lower submember of Member 2 of Lianggaoshan Formation formed in a warm
humid
strongly reducing
and highly productive freshwater environment
characterized by well-developed silt laminae and a high content of feldspar minerals. The combination of Type Ⅱ
1
toⅡ
2
kerogens
medium to high organic carbon content
a high degree of thermal maturity
and high-quality crude oil indicates the development of volatile oil reservoirs in shale. The reservoirs exhibit distinctive geological characteristics
including predominantly inorganic pores and fractures
large pores and throats
integrated pore-fracture networks
and fracture-enhanced drainage. The lacustrine dark shale in the upper oil-bearing layer of lower submember of Member 2 of Lianggaoshan Formation is characterized by excellent material foundation
favorable accumulation configuration
good preservation conditions
and effective fractures
making it a geological-engineering dual sweet spot. This improves reservoir stimulation and enhances hydrocarbons production. To address the challenges associated with terrestrial shale exploration and evaluation
continuous efforts and breakthroughs have been made in well logging
geophysical prospecting
and engineering techniques
thus creating a series of novel
applicable technologies. The discovery of Fuxing oilfield plays a crucial role in advancing the understanding of terrestrial petroleum geology
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Geological characteristics and beneficial development scheme of shale gas reservoirs in complex tectonic regions:a case study of Wufeng-Longmaxi formations in Sichuan Basin and its periphery
Geological characteristics, formation conditions and accumulation model of deep and ultra-deep,high-porosity and high-permeability clastic reservoirs: a case study of Gulf of Mexico Basin
“Exploring petroleum inside or near the source kitchen”: innovations in petroleum geology theory and reflections on hydrocarbon exploration in key fields
Related Author
Guo Tonglou
He Xipeng
Zeng Ping
Gao Yuqiao
Zhang Peixian
He Guisong
Zhang Xingwen
Pang Xiongqi
Related Institution
Sinopec East China Oil and Gas Company
College of Geosciences, China University of Petroleum
State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum
PetroChina Research Institute of Petroleum Exploration and Development
Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences