石油与天然气地质2026，Vol.47Issue(3)：972-984,13.DOI:10.11743/ogg20260317
川中地区侏罗系凉高山组砂岩储层微观特征及其成因机理
Microscopic characteristics and genetic mechanisms of the Jurassic Lianggaoshan Formation sandstone reservoirs,central Sichuan Basin
摘要
Abstract
The study systematically characterized reservoir characteristics and highlighted primary factors controlling reservoir tightening based on cast thin-section petrography and petrophysical analysis of core samples from five wells,including well G119.The research results show that the Lianggaoshan Formation sandstones in the central Sichuan Basin exhibit fine-grained,well-sorted texture;however,lithofacies vary significantly across different systems tracts.The transgressive systems tract(TST)is characterized by quartz sandstones and lithic quartz sandstones featuring high quartz and low feldspar contents alongside unstable sedimentary lithic fragments,whereas the highstand systems tract(HST)predominantly develops lithic sandstones and feldspathic lithic sandstones.The quartz-rich sandstones of the TST is collectively controlled by the forebulge gentle slope setting,distal provenance,intense hydrodynamic winnowing,and"relay quartz supply"sourcing from the weathered horizons of the pre-existing alluvial plain.The sandstones exhibit an average porosity of 2.56%and an average permeability of 0.11×10⁻3 µm2.Intense compaction(accounting for an average loss of 83.5%of primary porosity)and early-stage pervasive calcite cementation(observed in 25%of samples)are the critical drivers of reservoir densification.Dissolution is poorly developed with a thin section porosity less than 0.5%),and this is primarily limited by the scarcity of soluble feldspar,rapid compaction rates,and insufficient organic acid supply from adjacent source rocks.By contrast,reservoirs relatively high in quality with an average porosity reaching 7.56%,are developed within distributary channel sandstones with low matrix content at the base of the TST.Excessively high quartz content increases the risks of wear to drill bit and hydraulic fracturing operations.HST sandstones,which possess higher feldspar and lithic contents than TST sandstones,offer better drillability and stimulation potential,serving as promising succession intervals for future exploration.关键词
石英含量/成因机理/砂岩储层/凉高山组/侏罗系/川中地区/四川盆地Key words
quartz content/genetic mechanism/sandstone reservoir/Lianggaoshan Formation/Jurassic/central Sichuan Basin/Sichuan Basin分类
能源科技引用本文复制引用
郑马嘉,秦春雨,辛佳艳,高武彬,侯克均,马廷虎,夏国勇,祝海华,丁修建,王明磊,张本健..川中地区侏罗系凉高山组砂岩储层微观特征及其成因机理[J].石油与天然气地质,2026,47(3):972-984,13.基金项目
国家自然科学基金项目(42202176) （42202176）
中国石油-西南石油大学创新联合体科技合作项目(2020CX050103). （2020CX050103）
