气候变化领域集成服务门户(CCPortal): Diagenetic alteration; pore-throat network; and reservoir quality of tight gas sandstone reservoirs: A case study of the upper Paleozoic sequence in the northern Tianhuan depression in the Ordos Basin; China

CCPortal

DOI	10.1306/08151919058
	Diagenetic alteration; pore-throat network; and reservoir quality of tight gas sandstone reservoirs: A case study of the upper Paleozoic sequence in the northern Tianhuan depression in the Ordos Basin; China
	Zhu S.; Zhu X.; Jia Y.; Cui H.; Wang W.
发表日期	2020
ISSN	0149-1423
起始页码	2297
结束页码	2324
卷号	104 期号:11
英文摘要	The Sulige gas field in the Ordos Basin is the largest gas field in China. The studied area, the northern Tianhuan depression, is located west of the gas field and is considered as a potential gas-producing area. The complex diagenetic alteration history and its effects on the pore-throat network and reservoir quality of the tight gas sandstones are explained. The upper Paleozoic first member of the Shanxi Formation and eighth member of the Shihezi Formation tight gas reservoir rocks are composed of coarse- to medium-grained sandstones and are dominated by sublitharenites. The most important diagenetic factor for porosity reduction was compaction, followed by cementation. Diagenetic mineral phases include quartz overgrowth, calcite cement and replacement, and kaolinite cement and replacement, with minor heulandite and chlorite. Pressure dissolution of quartz grains and quartzite fragments is the main source of silica for the early and late quartz overgrowth cementation (formed mainly from 120°C to 140°C). The hydrolysis and alteration of volcanic material and mica flakes released some silicon, calcium, and aluminum ions. Calcium and carbon in calcite cements could be derived from surrounding mudstones. Calcite replaced the quartz overgrowths. The formation of kaolinite, as cement and replacements, was controlled by the interactions of silica, aluminum, pH, and temperature (140°C). Because of deformation of detrital components (mica flakes and ductile rock fragments) and diagenetic replacement, clear negative correlations between reservoir quality and contents of the diagenetic minerals are lacking. A complex and isolated pore-throat network was created by strong diagenetic transformation. Based on analysis of thin sections, three-dimensional x-ray micro-computed tomography, and constant-rate mercury injection data, the samples with relatively good reservoir quality (porosity >10% and permeability >0.5 md) are characterized by dissolution pores and primary intergranular pores and commonly contain more and larger pore throats both in volume (counts >1800 and size >0.02 per unit volume) and diameter (>1.20 mm) than the samples with poor reservoir quality. The intercrystalline pores of kaolinite are very widespread and considered favorable for oil and gas accumulation because some asphalt was found within these pores. This study may be used, by analogy, to better understand diagenetic factors controlling the formation of tight gas sandstone reservoirs and predict the development of pore-throat systems. Copyright © 2020. The American Association of Petroleum Geologists. All rights reserved.
英文关键词	Aluminum; Calcite; Calcium; Cementing (shafts); Cements; Complex networks; Computerized tomography; Dissolution; Gases; Kaolinite; Metamorphic rocks; Mica; Petroleum reservoir engineering; Petroleum reservoirs; Porosity; Quality control; Quartz; Sandstone; Textures; Zeolites; Diagenetic alteration; Diagenetic transformation; Intercrystalline pores; Medium-grained sandstones; Oil and gas accumulation; Pressure dissolution; Tight gas sandstone reservoirs; X ray micro-computed tomography; Tight gas; asphalt; cementation; deformation mechanism; detrital deposit; diagenesis; mudstone; Paleozoic; pore space; reservoir; sandstone; sedimentary sequence; China; Nei Monggol; Ordos Basin; Shanxi; Shihezi; Sulige Gas Field; Xinjiang Uygur
语种	英语
来源期刊	AAPG Bulletin
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/168683
作者单位	State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing, China; College of Geosciences, China University of Petroleum, Beijing, China; College of Geosciences, China University of Petroleum (Beijing), Beijing, China
推荐引用方式 GB/T 7714	Zhu S.,Zhu X.,Jia Y.,et al. Diagenetic alteration; pore-throat network; and reservoir quality of tight gas sandstone reservoirs: A case study of the upper Paleozoic sequence in the northern Tianhuan depression in the Ordos Basin; China[J],2020,104(11).
APA	Zhu S.,Zhu X.,Jia Y.,Cui H.,&Wang W..(2020).Diagenetic alteration; pore-throat network; and reservoir quality of tight gas sandstone reservoirs: A case study of the upper Paleozoic sequence in the northern Tianhuan depression in the Ordos Basin; China.AAPG Bulletin,104(11).
MLA	Zhu S.,et al."Diagenetic alteration; pore-throat network; and reservoir quality of tight gas sandstone reservoirs: A case study of the upper Paleozoic sequence in the northern Tianhuan depression in the Ordos Basin; China".AAPG Bulletin 104.11(2020).