Drilling hazard assessment for hydrate bearing sediments including drilling through the bottom-simulating reflectors
Drilling hazard assessment for hydrate bearing sediments including drilling through the bottom-simulating reflectors
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DOI：
10.1016/j.marpetgeo.2014.08.007
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发表时间：
2014-12
影响因子：
4.2
通讯作者：
S. Wegner;K. J. Campbell
中科院分区：
文献类型：
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作者：
S. Wegner;K. J. Campbell
为了实现NGHP Expedition 01项目的科学目标，作为初步步骤，有必要检查现有的海洋二维地震数据，这些数据涵盖了当时拟议的潜在钻井地质灾害调查钻井地点。对位于北方印度洋近海地区的19个潜在钻井地点进行了调查：克里希纳-戈达瓦里盆地、喀拉拉-康坎盆地、马哈纳迪盆地和安达曼群岛。NGHP Expedition 01工作人员确定了每个现场需要调查的几个潜在钻井危险，包括但不限于海底斜坡和故障条件、复杂海底地形和异常振幅响应、浅层天然气水合物、浅层游离气、浅层水流和断层/裂缝等常见钻井危险。根据每个地点的具体计划深度，从海底开始，延伸到海底以下350-700米的深度范围内，对具体的拟议钻探地点进行了调查。这些调查的结果是，一些地点被解释为没有潜在的钻井地质灾害，而其他地点被确定为有可能发生足以重新考虑的特定地质灾害。这些重新考虑包括将特定地点移动到更有利的位置，这些位置被解释为相对不容易或不太容易受到特定已识别地质灾害的影响，和/或减少计划的钻探深度，或至少暂时从考虑中删除潜在地点。这项工作有助于NGHP Expedition 01的有利结果，因为据报道没有遇到钻井地质灾害。
To achieve the scientific goals of the NGHP Expedition 01 project, it was necessary as a preliminary step to examine the available marine 2-D seismic data covering then-proposed investigation drilling sites for potential drilling geohazards. A total of 19 potential drilling sites, located in offshore areas of the northern Indian Ocean: the Krishna–Godavari Basin, the Kerala–Konkan Basin, the Mahanadi Basin, and the Andaman Islands, were investigated. The NGHP Expedition 01 staff identified several potential drilling hazards to be investigated at each site, including, but not limited to, the common drilling hazards of seafloor slopes and failure conditions, complex seafloor topography and anomalous amplitude response, shallow gas hydrates, shallow free gas, shallow water-flow, and faults/fractures. Specific proposed drilling sites were investigated over a depth range beginning at the seafloor and extending to 350–700 m below the seafloor, depending upon the specific planned depth at each site. These investigations resulted in some sites being interpreted to be clear of potential drilling geohazards, while other sites were determined to have potentials for specific geohazards significant enough for reconsideration. These reconsiderations consisted of moving specific sites to more favorable locations interpreted to be relatively unsusceptible or less susceptible to a specific identified geohazard, and/or reducing the planned depth of drilling, or removing a potential site at least temporarily from consideration. This work contributed to favorable results from the NGHP Expedition 01 in that no drilling geohazards were reportedly encountered.