Characteristics of the Permian Reservoirs From Taiyuan Formation in Shenmu Gas Field

The petrographic, physical and pore throat characteristics and heterogeneity of the reservoirs from the Taiyuan Formation in the Shenmu gas field, comprehensive application mainly on core observation, cast section, scanning electronic microscope, grain-size analysis and mercury-injection curves.There are the lithic quartz-sandstone, quartz sandstone, and lithic sandstones with high compositional maturity and medium textural maturity.The reservoir has low porosity and low permeability.The average porosity is 7.8% and the average permeability is 0.64×10-3μm2.The pore space of the reservoir mainly includes the secondary dissolved pores between grains, and rock fragment-dissolution pores plays a vital role in dissolved pores.The main factors influencing the reservoir capacity include sedimentary environments and diagenesis.Sedimentary environment is the root cause of poor reservoir property, peat diagenesis and cementation are responsible for poor physical properties of the reservoirs, and dissolution led to the modification of the reservoirs.