苏北地区浅层油气成藏特征与勘探前景

CHARACTERISTICS OF THE FORMATION OF SHALLOW OIL AND GAS RESERVOIRS IN NORTH JIANGSU AND THEIR EXPLORATION POTENTIAL

根据油气遥感、浅层地震、化探、钻井等资料的综合勘探、研究 ,探讨了浅层油气的成藏特征和控制因素 ,评价出苏北地区浅层油气勘探的 6个浅层含油气区带。其中 ,许庄、江都—吴堡地区和泰兴—海安地区属于有利区带 ,也是近期浅层油气勘探的主要试验勘探区带。浅层油气的成藏 ,具有多来源的油气 ,储层物性好、盖层条件理想 ,为油气的成藏形成良好的储盖组合。气藏类型以岩性圈闭和低幅度构造圈闭为主 ,油气层埋藏深度一般为 5 0 0～ 10 0 0m ,一般为 80 0m左右。初步预测江苏地区浅层油气资源量可达 (397.4 4～ 14 18.5 5 )× 10 8m3 ,其中 ,江都—吴堡区带的资源量为 (177.5 4～ 5 0 3.0 4 )× 10 8m3 ;泰兴—海安区带的资源量为 (130 .6 0～ 6 0 4 .6 1)× 10 8m3 。因此 ,该区浅层油气的勘探具有良好的前景。

The oil and gas shows were often found in drilling the shallow layers (Neogene) in North Jiangsu. In recent years,through remote sensing imaging,shallow seismic exploration,geochemical exploration and drilling,the characteristics of the formation of shallow oil and gas reservoirs and their control factors were comprehensively studied and discussed,and six oil-and gas-bearing zones were evaluated for shallow oil and gas exploration in North Jiangsu,in which the Xuzhuang,Jiangdu-wubao and Taixing-Hai′an regions are the favourable zones and also the mainly experimental areas of shallow oil and gas exploration. The formation of shallow oil and gas reservoir must have a perfect source-reservoir-caprock assemblage,i.e. multiple hydrocarbon source,good petrophysical property and ideal caprocks. The gas reservoirs mainly belong in lithologic traps and low-amplitude structural traps and their burial depths are 500—1000 m,being about 800 m in general. The shallow hydrocarbon resources predicted initially for North Jiangsu might be up to 39744×106—141855×106m3;those for Jiangdu-Wubao region 17754×106—50304×106m3;and those for Taixing-Hai′an region 13060×106—60461×106m3. Therefore the shallow oil and gas reservoirs in North Jiangsu are of good exploration potential.