海洋灾害地质风险评价在辽东湾浅海油气开发区的应用

基于在辽东湾浅海油田多年调查获取的地质地球物理资料,构建以油气开发区潜在灾害地质类型为基础的灾害地质风险评价指标体系,确定潮流冲刷槽、浅滩、埋藏古河道、易液化砂层、软弱地层和浅层气等6个评价指标,利用层次分析法(AHP)确定各指标的权重值,采用模糊数学评判法对海区灾害地质风险性作定量评价。评价结果划为5级风险区(风险高、较高、中等、较低和低),其中,潮流冲刷槽为本区的高风险区,地势平缓的潮滩为低风险区。评价结果与区内已建海洋工程的评价分析相互印证,对海上工程建设具有实际应用价值。

APPLICATION OF GEOHAZARD RISK ASSESSMENT IN THE SHALLOW-SEA OIL-GAS DEVELOPMENT AREA OF LIAODONG BAY

Based on sufficient geological and geophysical data in the shallow water oil-gas development area of the Liaodong Bay, a geohazard risk assessment index system was established according to the local potential geohazard types. Tidal scour trough, shoal, buried paleo-channel, liquefaction sand layer, soft layer and shallow gas were identified as 6 indicators. Weight values were determined using analytic hierarchy process(AHP). Then a fuzzy comprehensive evaluation model was established to quantitatively assess the geohazard risk of the study area. According to the results, the study area was divided into five regions on risk-level. The distribution area of tidal scour trough has the highest risk and the flat shoal is the lowest. The results are consistent with the geohazard assessment made by some construction projects in the study area and will be beneficial to the offshore engineering in the future.