【摘要】 浅水流(Shallow Water Flow,SWF)是深水环境海底浅部地层中超压的砂体流动,是对深水钻井最具破坏力的一种地质灾害,严重制约深水油气开发.为有效预测和防治浅水流,需要对浅水流地球物理特性进行研究,并在研究区内加以识别.本文借鉴国外主要深水盆地对浅水流问题的研究经验,对南海北部深水盆地潜在浅水流区域采取以属性判定、超压分析为主,振幅识别为辅的方法进行预测.精细层序地层学解释发现,南海北部深水盆地存在上新世以来的古珠江深水水道沉积体系和第四纪水道,这些水道砂体疏松未固结、孔隙度大、有效应力低、几乎表现出流体特性.基于遗传算法的混合反演方法发现,研究区存在典型的AVO响应,横波速度极低,低频特征明显,振幅强度弱,连续性较好,存在极性反转,高泊白松比和高纵横波速度比.研究结果表明,南海北部陆坡具备浅水流发生的潜在条件,深水水道发育区为潜在的浅水流危险区,浅水流具有独特的地震响应特征,泊松比高达0.49,纵横波速度比约为3.5～9或更高,SWF层位对地震属性的敏感度V_P/V_S>AVO响应>泊松比.更多还原

【Abstract】 With the development of deepwater drilling, deepwater geohazards have become a challenge.Shallow water flow (SWF) is one type of the most serious geohazards in deepwater drilling.SWF hazards are only met in deepwater regions and SWF sands have the properties of low density, low velocity and high V_P/V_S.Based on the theory of Sequence Stratigraphy, the deepwater channel depositional system was identified in Baiyun depression, Pearl River Basin. With the result of AVA inversion, fullwave inversion and poststack inversion, the region with low density, low velocity and high V_P/V_S(>9) value were refined in which the SWF may happen.更多还原