塔北志留系浅变质低孔隙度裂缝性砂岩储层测井评价

Log Evaluation of Epimetamorphic Sandstone Reservoirs with Low-porosity and Fractures in Silurian in North Tarim Basin

针对塔里木盆地塔北地区志留系海相浅变质裂缝性砂岩油藏,系统分析、总结了砂岩储层低孔隙度低渗透率的成因以及裂缝对储层渗流能力的影响;指出对致密裂缝性砂岩储层,微电阻率成像测井资料的采集应当作为必测资料,建立了一套基于微电阻率成像测井资料为主体,结合常规测井资料的低孔隙度裂缝性砂岩油藏有效储层测井评价方法与评价标准;借鉴碳酸盐岩储层评价方法的经验,结合储层中裂缝的发育程度与产层的有效下限,给出了该区砂岩储层精确的基质孔隙度下限标准值。由此,提高了塔北志留系储层测井评价精度。

To evaluate the epimetamorphic marine sandstone oil reservoirs with fractures in Silurian, north Tarim Basin, systematically analyzed and summarized are the origin of sandstone reservoirs with low-porosity and low-permeability and influence of fractures on seepage ability; Micro- resistivity imaging log data acquisition is a must for compacted and fractured sandstone reservoir. Established are a suit of valid log evaluation methods and criterions of sandstone oil reservoirs with low-porosity and fractures based on the microresistivity imaging log data and conventional log data; Pointed out is correlation between the growth degree of fractures and valid minimum of producing layers according to experience of evaluating carbonate reservoir; Given is the accurate low limited standard value for matrix porosity in the Silurian sandstone reservoir. Therefor log evaluation accuracy of reservoirs in Silurian of north Tarim Basin with the above methods.