Micropores of shale are significant to the gas content and production potential of shale, which has been verified in the research of marine shale gas; while, few studies have been conducted on lacustrine shales. This ...Micropores of shale are significant to the gas content and production potential of shale, which has been verified in the research of marine shale gas; while, few studies have been conducted on lacustrine shales. This study collected 42 samples from three wells in the Late Cretaceous Qingshankou Formation of the southern Songliao Basin, NE China, and investigated these samples by the focused ion beam-scanning electron microscope(FIB–SEM) and nitrogen adsorption analysis techniques. Four types of micropores were identified in the samples, i.e., intergranular pore, intracellular pore, organic matter pore and microfracture. The pore structure type is characterized by open slit pores and "ink type" pores which are mainly 1.5–5 nm in diameter with mesopores as the main pores. The mesopores account for 74.01% of the pore volume and 54.68% of the pore surface area. Compared with the lacustrine shales from the Triassic Yanchang Formation in the Ordos Basin and Xujiahe Formation in the Sichuan Basin, the intergranular clay mineral interlayer pores are considered to be the main reservoir space for shale gas storage in the study area, followed by intraparticle pores, organic matter pores and microfractures. Maturity and micropore are the key controlling factors which affect the shale gas content of the Qingshankou Formation in southern Songliao Basin.展开更多
Objective Paleosols in terrestrial deposits provide important insight into paleoclimate and tectonic events(Gong Hujun et al., 2017). The Late Cretaceous continental red bed in the Songliao Basin of NE China records t...Objective Paleosols in terrestrial deposits provide important insight into paleoclimate and tectonic events(Gong Hujun et al., 2017). The Late Cretaceous continental red bed in the Songliao Basin of NE China records the paleoclimate characteristics during the Cretaceous greenhouse period. A series of data has been obtained from cores in continental scientific drilling wells(Wang, 2013). However, few investigations have reported on paleoclimatic and tectonic展开更多
A number of isolated fault sags in Late Jurassic--Early Cretaceous were developed in the early stage of southern Songliao Basin,and unified to a depression basin in the late stage.Therefore,multiple isolated lower pet...A number of isolated fault sags in Late Jurassic--Early Cretaceous were developed in the early stage of southern Songliao Basin,and unified to a depression basin in the late stage.Therefore,multiple isolated lower petroliferous systems were formed with fault sags as source rocks.The source rocks of fault sags in Late Jurassic--Early Cretaceous were mainly described with gas generation as favorable source rocks,leading to the southern Songliao Basin rich in natural gas resources combined with organic gas resources in Nenjiang Formation.A number of tectonic movements in southern Songliao Basin led to the formation of abundant structural traps and complex fault systems,and controlled the distribution strata and positions of sources rocks in Late Jurassic--Early Cretaceous fault sags.The oil-gas reservoirs can be divided into two types,i.e.,primary and secondary ones.The primary oil-gas reservoirs were distributed in the fault sag strata and the bottom of overlying depression strata(lower Quan-1 Member).The oil-gas reservoir accumulation depended on the trap development situation and the distance from source rocks.The preservation conditions of oil-gas reservoirs depended on the degree of reconstruction in the late tectonism.The secondary oil-gas reservoirs were distribution in the Quantou Formation of depression strata,where oil and gas reservoir accumulation depended on three conditions,i.e.,trap development situation,deep gas sources and the fault to connect the shallow traps and deep gas sources.The southern Songliao Basin is rich in lower coal type gas,upper oil-gas and biogas resources,which are important resources in the future.展开更多
基金financially supported by the National Natural Science Foundation of China (grant No. 41702171)a National Science and Technology Major Project (grant No. 2016ZX05034002)
文摘Micropores of shale are significant to the gas content and production potential of shale, which has been verified in the research of marine shale gas; while, few studies have been conducted on lacustrine shales. This study collected 42 samples from three wells in the Late Cretaceous Qingshankou Formation of the southern Songliao Basin, NE China, and investigated these samples by the focused ion beam-scanning electron microscope(FIB–SEM) and nitrogen adsorption analysis techniques. Four types of micropores were identified in the samples, i.e., intergranular pore, intracellular pore, organic matter pore and microfracture. The pore structure type is characterized by open slit pores and "ink type" pores which are mainly 1.5–5 nm in diameter with mesopores as the main pores. The mesopores account for 74.01% of the pore volume and 54.68% of the pore surface area. Compared with the lacustrine shales from the Triassic Yanchang Formation in the Ordos Basin and Xujiahe Formation in the Sichuan Basin, the intergranular clay mineral interlayer pores are considered to be the main reservoir space for shale gas storage in the study area, followed by intraparticle pores, organic matter pores and microfractures. Maturity and micropore are the key controlling factors which affect the shale gas content of the Qingshankou Formation in southern Songliao Basin.
基金funded by the “Major Science and Technology Projects of the CNPC (grant No. 2016B-0401)”
文摘Objective Paleosols in terrestrial deposits provide important insight into paleoclimate and tectonic events(Gong Hujun et al., 2017). The Late Cretaceous continental red bed in the Songliao Basin of NE China records the paleoclimate characteristics during the Cretaceous greenhouse period. A series of data has been obtained from cores in continental scientific drilling wells(Wang, 2013). However, few investigations have reported on paleoclimatic and tectonic
文摘A number of isolated fault sags in Late Jurassic--Early Cretaceous were developed in the early stage of southern Songliao Basin,and unified to a depression basin in the late stage.Therefore,multiple isolated lower petroliferous systems were formed with fault sags as source rocks.The source rocks of fault sags in Late Jurassic--Early Cretaceous were mainly described with gas generation as favorable source rocks,leading to the southern Songliao Basin rich in natural gas resources combined with organic gas resources in Nenjiang Formation.A number of tectonic movements in southern Songliao Basin led to the formation of abundant structural traps and complex fault systems,and controlled the distribution strata and positions of sources rocks in Late Jurassic--Early Cretaceous fault sags.The oil-gas reservoirs can be divided into two types,i.e.,primary and secondary ones.The primary oil-gas reservoirs were distributed in the fault sag strata and the bottom of overlying depression strata(lower Quan-1 Member).The oil-gas reservoir accumulation depended on the trap development situation and the distance from source rocks.The preservation conditions of oil-gas reservoirs depended on the degree of reconstruction in the late tectonism.The secondary oil-gas reservoirs were distribution in the Quantou Formation of depression strata,where oil and gas reservoir accumulation depended on three conditions,i.e.,trap development situation,deep gas sources and the fault to connect the shallow traps and deep gas sources.The southern Songliao Basin is rich in lower coal type gas,upper oil-gas and biogas resources,which are important resources in the future.
