Abstract:

The volcanic rocks of the Lower Es3 in Oulituozi region are mainly volcaniclastic rock,basalt and trachyte.The volcanic rock diagenesis and reservoir space evelution are studied.It is considered that,different deposition stages have different paleo geothermal gradients,and different diagenetic stages correspond to different depths.Thick volcanic rocks from Sha-1 mumber to present are in the early diagenetic B-stage;the reservoir spaces are generally fissure-primary porosity and fissure compound porosity,and are poorly preserved;the volcanic rocks in the lower part are mainly well-developed fissure-secondarfy porosity.

Key words: Oulituozi, volcanic rock, diagenesis, pore evolution