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.