The Relationship between Diagenetic Evolution and Hydrocarbon Charge in Deep Tight Reservoirs: A Case Study from Kepingtage Formation of S9 Well Block in Tarim Basin

The Silurian Kepingtage Formation of Tarim Basin is an important deep clastic reservoir. Exploration practice shows that the reservoirs are generally characterized by extremely low porosity and permeability, exhibiting strong mineral composition physical property heterogeneities. study heterogeneity its effect on oil charge great significance to understanding migration accumulation in such thus crucial exploration. Therefore, based identification quantitative statistics thin sections, SEM, homogenization temperature measurements, this was designed examine relationship between diagenetic evolution emplacement S9 Block Basin. control differential diagenesis process discussed. It found sandstones with fine grain size high content ductile grains (>20%) have experienced mechanical compaction, decreases rapidly early stage burial. densification has been completed before first period so no In contrast, relatively coarse better permeability properties, which oil-bearing. This kind sandstone two periods charge. Apart from moderate multiple events were also observed, including quartz cementation, calcite dissolution. Before charge, dominated chlorite dissolution, reservoir still high. seems time late long. With growth types authigenic minerals as quartz, calcite, illite after or sometimes synchronously occurred gradually decreases.