海上气田生产后期深层挖潜砂体预测——以西湖凹陷X气田为例

西湖凹陷X气田是东海最早开发投产的油气田之一,已进入生产后期,油气产量较低,难以维持气田生产经济性。其主力产层主要分布在花港组,经过十多年的开发调整,花港组储量动用程度高,为缓解气田严峻的生产形势,其挖潜方向转向深层,由于该区深层平湖组钻井资料较少,加上埋深较大,目前研究和探明程度总体偏低,制约了该气田的下步挖潜部署。采用地震属性分析、反演解释等技术,结合测井、录井、岩心等资料,对研究区平湖组P1、P2、P3共3个重点含气层段砂体进行精细解剖,结果表明:平湖组砂体累计厚度较大,横向上连片性好;纵向上P2砂体厚度明显较P1、P3大,反映P2分支河道砂体更为发育。最后结合预测结果划出研究区内具有两个相对砂体富集区带,对该气田后期挖潜和井位部署具有重要指导意义。

Prediction of deep dredging potential sand body in late production period of offshore gas field: a case study of X gas field in Xihu sag

X gas field in Xihu sag is one of the earliest oil gas fields to be developed and put into production in the East China Sea. It has entered the later stage of production and the oil gas output is low, which makes it difficult to maintain the economical production of the gas field. After more than ten years of development and adjustment, the reserves of Huagang Formation are highly utilized. In order to alleviate the severe production situation of the gas field, the exploration turns to the deep layer. Due to the lack of drilling data and depth of strata of deep Pinghu Formation, the degree of research and exploration is generally low, which restricts the next step of potential exploitation and deployment of the gas field. This paper uses seismic attribute analysis, inversion interpretation and other techniques, combined with logging, core and other data, the sand bodies of the three key gas-bearing intervals (P1, P2 and P3) are elaborately dissected. The result shows that the accumulated thickness of sandbodies in Pinghu Formation is large, with good lateral continuous. Longitudinally, the thickness of P2 sand body is obviously larger than that of P1 and P3, which reflects that P2 channel sand body is more developed. Finally, combining with the prediction results, two sand enrichment zones are identified, which has important guiding significance for the exploitation and well deployment in the later stage of the gas field.