深水钻井中浅层水流的预防与控制方法

Prevention and control methods for shallow water flow in deepwater drilling

张辉 高德利 刘涛 唐海雄

ZHANG Hui GAO Deli LIU Tao TANG Haixiong

中国石油大学石油工程学院，北京　102249 中海油深圳分公司，广东深圳　518067

Department of Petroleum Engineering, University of Petroleum, Beijing 102249, China CNOOC Shenzhen Branch, Shenzhen 518067, China

浅层水流是深水钻井中常见的地质灾害之一，由此所造成的经济损失是十分巨大的。如何避免和减轻可能要面对的浅层水流灾害是一个很有挑战性的课题。因此非常有必要开展相关预防与控制方法研究。介绍了诱发浅层水流的4种机理，分别为：高压砂体机理、裂缝诱导机理、流体储藏诱导机理以及高压传递机理。根据浅层砂体的特性和浅层水流诱导机理，提出了浅层水流钻前预防方法和钻井过程中浅层水流预防方法。针对已识别的浅层水流，归纳总结了控制浅层水流发生的5种方法：提高钻井液密度、使用海底分流器、使用化学钻井液、泡沫胶结固井以及使用导管穿过浅层水流层。该研究对于深水钻井中有效地预防和控制浅层水流的发生具有重要意义。

Shallow water flow（SWF）is a kind of common geological hazards in deepwater drilling, which has caused a large amount of financial loss. Deepwater hydrocarbon resource is being explored in China, and it is a very challenging issue to avoid and alleviate the potential harm of SWF. So it is essential to study on the prevention and control method for SWF. Four different mechanisms causing SWF were introduced: fracture inducing, storage inducing, geopressured sands in conductor intervals and transmission of geopressure through cement channels. According to the characteristics of geopressured sands and the mechanisms causing SWF, the corresponding precautions of SWF before drilling and in the process of drilling were proposed. Based on the identified SWF, five means for preventing SWF were summarized: increasing mud weight, using a seafloor diverter, using chemical grout, cementing with foamed slurry and driving the conductor through the SWF zone. The research plays an important role in preventing and controlling the deepwater SWF effectively.