Abstract: The study area（western Hubei—eastern Chongqing）was a transitional zone between steep detachment fold belt
in eastern Sichuan and block-basement fault-fold belt in western Hunan—Hubei. There the deformation is relatively weak，
and oil & gas geological preservation condition was better than surrounding areas. Based on the well drilling and field data，
employing the petrology，thin section，SEM and organic geochemical analysis，we studied the characteristics of the macro and
micro Silurian reservoir rocks and their oil & gas prospection. The results show that：the main lithology of Longmaxi Formation
was black carboniferous shale，deep gray（gray）shale and silty mudstone. The micro-reservoir spaces were highly developed
including intergranular dissolution pores of clay minerals，dissolution pores in feldspar and quartz，microfratures and so on.
Source rocks with high quality were developed east to the belt of Well Jianshen 1 and Lengshuixi. And the microporosity and
microfractures were very rich in Silurian. The Silurian Hanjiadian Formation gas reservoir belonged to tight gas. Based on
the Well Jianshen 1 gas reservoir characteristics and the existing drilling analysis data，we conclude that Shizhu composite
anticline，Lichuan and Huaguoping composite syncline are fully equipped with tight gas and shale gas exploration potential.

Key words: Silurian, characteristics of reservoir rocks, unconventional gas reservoir, western Hubei—eastern Chongqing