| 摘要: |
| 灾害地质学(hazard geology)是研究对海底工程,特别是海洋石油工程能够产生直接危害,或具有潜在性危害的地质因素的特征及分布规律的科学。在过去几十年的海上石油开发中,由于事先未能对灾害性地质进行详细调查而造成重大损失的事件不乏其例。1973年3月,墨西哥湾一钻井平台,因浅层天然气喷发引起火灾,数千万美元的仪器设备毁于一旦。1977年南海莺歌海盆地作业的一架自升式钻井平台,在水深75m处插桩时,由于埋藏古河道的影响,地层分布不连续，两只柱腿插在古河岸上,至海底以下3m即稳定,另一只桩腿落入古河床,插入21m尚不稳定,致使钻井平台倾斜,后被迫移位才免遭于害。灾害性地质问题的研究已成为海洋石油和天然气开发成败的关键问题之一,因而引起了国内外有关部门的极大重视。1985-1987年,中国科学院海洋研究所受南海西部石油公司的委托,对珠江口以西至北部湾东部的广大海域,进行了大规模的灾害性地质、工程地质的普查及井位调査。调查中先后使用了“科学一号”科学考察船和“南海502”、“南海503”等工程物探及工程地质调查船,在海上进行了七千余公里的综合性工程物探测量,为研究调查区灾害性地质问题积累了丰富的资料。 |
| 关键词: 南海西部、灾害性地质 |
| DOI： |
| 分类号: |
| 基金项目:中国科学院海洋研究所调查研究报告第1697号 |
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| STUDY ON HAZARD GEOLOGY IN WEST PART OF THE NORTHERN SOUTH CHINA SEA |
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Li Fan
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Institute of Oceanology, Academia Sinica
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| Abstract: |
| During 1985-1988, characteristics, distributions, genesis and correlation between some geohazards factors were investigated in west part of the northern South China Sea. There are various geohazards factors or unstable factors on sea floor in west part of the northern South China Sea, such as submarine active sand dune, tidal current sand ridge, pockmark, submarine steep-slope and scarp, continental shelf marginal valley, mud flow, submarine erosion and erosional residue hill, buried paleo-channel, buried paleo-lake, buried paleo-delta,marsh-gas and shallow high pressure gas, slump fault and active fault, submarine landslide. According to their locations and hazardous effect, geohazards factors can be divided into two categories:sea floor geohazards and underground geohazards. The former is of geomorphological and geologioal nature, endangering submarine constructions on sea floor. The latter is exclusively of geological nature. Based on the latency and dangerous degree of hazards, each category of geohazards factors could be divided into three types: immediate hazard factors, latent hazard factors and constraint hazard factors. The investigated area can also be divided into various geohazard zones as follows: immediate sea floor hazard zone, latent sea floor hazard zone, immediate sea floor constraint hazard zone, sea floor basically no hazard zone, immediate underground hazard zone, latent underground hazard zone, underground constraint hazard zone and basically no hazard zone. |
| Key words: HAZARD GEOLOGY,WEST PART OF THE NORTHERN SOUTH CHINA SEA |
