成都理工大学学报（自然科学版）2026，Vol.53Issue(2)：352-366,15.DOI:10.12474/cdlgzrkx.2024070901
鄂尔多斯盆地定北上古生界致密砂岩储层脆性特征及影响机理
Brittleness characteristics and influencing factors of Upper Paleozoic tight sandstone reservoirs in the Dingbei area of Ordos Basin
摘要
Abstract
The brittleness of the Upper Paleozoic tight sandstone reservoirs in the Dingbei area and the corresponding impact factors are of great practical significance when selecting the"sweet spot"between project development and exploration risk assessment.Based on X-ray diffraction measurements,scanning electron microscopy,rock mechanics experiments,and core thin section and physical data,the mineral components and mechanical brittleness characteristics of the tight sandstone reservoirs in the study area were analysed and evaluated,with the aim of identifying the main controlling factors of the brittleness and its influencing mechanism(s).This study shows that the brittleness of tight sandstone reservoirs in the Upper Paleozoic Tai-2 member of the Shanxi Formation and the He-1 member in the Dingbei area is mainly affected by the mineral components and structure of the rocks.Among them,the quartz and clay mineral contents have the largest influence on the brittleness of the rocks.When the contents of these mineral components are similar,the particle-supported structure formed by coarse-grained sandstone has a relatively high brittleness,and the mechanical properties of the mineral structure are mainly affected by modification via diagenetic action.In the study area,the tight sandstone reservoirs of the Tai-2 section as a whole show the lithogenic evolution mode of"strong compaction-strong dissolution-strong cementation,"where the mineral structure is closely connected,and the brittleness is relatively good.The distribution of brittleness is mainly affected by the depositional environment,whereby the coarse-grained sandstone is more developed and has higher quartz content in diversion channels resulting from stronger hydrodynamic conditions,implying they are high-quality mechanically brittle reservoirs.These research results have important reference significance for deepening our understanding of brittleness of tight sandstone reservoirs and evaluating"sweet spot"from engineering perspective.关键词
致密砂岩/岩石力学/脆性/成岩作用/影响机理Key words
tight sandstone/rock mechanics/brittleness/diagenesis/influence mechanism分类
天文与地球科学引用本文复制引用
沈杰,徐浩,李国峰,万洋,邓虎成,何建华,刘岩,邓乃尔..鄂尔多斯盆地定北上古生界致密砂岩储层脆性特征及影响机理[J].成都理工大学学报（自然科学版）,2026,53(2):352-366,15.基金项目
国家科技重大专项(2025ZD1403903-02) （2025ZD1403903-02）
国家自然科学基金(4247020708,42202189). （4247020708,42202189）
