LITHOLOGIC AND LITHOFACIES PATTERNS OF VOLCANIC RESERVOIRS IN XUSHEN GAS FIELD

Xushen-1 tested a large gas flow rate over 1 MMCMD from volcanic reservoirs in 2002 and since then exploration and development of the deep volcanic gas pools began in Daqing oil complex.The Xushen gas field has become the largest gas field discovered in the eastern onland China,with gas reserves accounting for 89.9% of the total in the study area.However,description of the volcanic reservoirs is the main bottleneck restraining exploration and development of deep gas in this area.This paper introduces a set of techniques for volcanic reservoir description,such as lithologic and lithofacies description of volcanic rocks,logging lithologic identification of volcanic rocks and seismic recognition of volcanic rock mass.These techniques provide a solid foundation for highly efficient development of the volcanic gas pools in Xushen gas field and fill the gap in comprehensive reservoir description of volcanic gas reservoirs in China.