Fracture Recognition Effect Analysis Of Different Acoustic And Electric Image Logging In Tight Sandstone Reservoir

The reservoirs of Bashijiqike Formation in Keshen area Kuqa Depression are characteristic of typical poor poor physical property which belong to fractured tight sandstone reservoirs,so that reservoirs fracture development characteristics directly impact oil and gas production capability.Fracture development influence factors and effectivity evaluation are important basis of reservoirs evaluation and exploration deployment.Furthermore,analysis of different acoustic-electric imaging logging fractures recognition results,selecting out suitable imaging logging method in the study area,providing the basis for the late tight sandstone reservoir imaging logging series selection.This study made deeply research and developed the experiment of fracture response of acoustic electric imaging logging,built up ‘Interactive changing window length fine imaging logging interpretation method' of different acoustical and electrical imaging well logging under ‘Core-scale logging',evaluated and contrasted the characteristic of fracture of Bashijiqike Formation in Keshen gas field,and determined the fracture acoustic-electric imaging logging response limit.The results indicate that the smaller the width of fracture,the harder it is to recognize the fracture using imaging logging;the response size to the geological body of the acoustical imaging logging is greater than the real,so that FMI is better than acoustical image logging(CBIL)to recognize geological body.FMI-HD image logging data of water base mud is better used to recognize fracture than of oil base mud;EI and FMI-HD image of oil base mud effect is not good,so that it is less reliable to recognize fracture;Borehole coverage rate of acoustical image logging(CBIL)is higher than the electric image logging which can reach to 100%.Quantitative imaging logging fracture parameters calculated show that fracture porosity contribution to the total porosity of the reservoirs is very small,while the fracture permeability makes permeability of total reservoir increased by 1 to 3 orders of magnitude.Current stress analysis of the study area by imaging logging,and evaluation of the relationship to current stress and deliverability,the results showed that direction to current stress and fracture orientation angle size is a key factor in fractured tight sandstone reservoir level of influence.