摘要
我国南海地块天然气水合物资源潜力巨大,目前已在南海北部神狐海域成功完成天然气水合物试采,取得了水合物勘探的重大突破,但其发育的地质条件、成藏因素、分布状态仍然不清,有必要进一步开展水合物形成条件及其分布的研究。笔者以南海油气勘查资料为基础,参考南海石油—天然气—天然气水合物已取得的成果,从沉积、构造、油气条件及水合物富集要素等方面,探讨南海天然气水合物成藏条件和分布规律。结果表明:①南海地块地壳厚度薄、热流值高,有利于有机质热演化;②中新生界发育三角洲、冲积扇、浊积扇、滑塌扇等沉积相类型,砂、泥呈互层状分布,可为天然气水合物提供良好成藏条件;③构造要素多样复杂,张性或张扭性断裂系统发育,可构成天然气运移通道;④发育生物气、浅层热解气、中深层热解气和油气田气等4类气源,为天然气水合物成藏提供良好的物质基础;⑤隆起与坳陷是天然气水合物富集成藏的有利部位。研究结果为天然气水合物勘探开发提供了指导,并为其他海域天然气水合物勘查提供科学依据。
In China,the South China Sea Block has great potential of natural gas hydrate resources.At present,the pilot production of natural gas hydrate has been successfully conducted in the Shenhu area,the northern part of the South China Sea,indicating a major breakthrough in hydrate exploration.However,the geological conditions,accumulation factors and hydrate distribution are still unclear,so it is necessary to further study the formation conditions and distribution of natural gas hydrate.Based on the oil and gas exploration data and the achievements of oil,gas and natural gas hydrate in the South China Sea,the accumulation conditions and distribution of natural gas hydrate in the South China Sea have been discussed in the aspects of sedimentation,structure,oil and gas conditions and hydrate enrichment factors.The results show that:①The thin crustal thickness and high heat flow value of the South China Sea Block are conducive to the thermal evolution of organic matter;②The sedimentary facies of delta,alluvial fan,turbidite fan and slump fan are developed in the meso-Cenozoic,and the sand and mud are interbedded,which provides favourable conditions for gas hydrate accumulation;③The diverse and complex structure elements such as tensional or transtensional fault system can form migration channel for natural gas hydrate;④Four types of gas resources such as biogas,shallow-layer pyrolysis gas,middle-deep pyrolysis gas and gas field gas are developed,which provide a good material basis for gas hydrate accumulation;⑤Uplifts and depressions are favorable locations for gas hydrate accumulation.The results not only provide the guidance for the natural gas hydrate exploration and development,but also provide scientific evidence for the natural gas hydrate exploration in other sea areas.
作者
康玉柱
KANG Yuzhu(Sinopec Exploration&Production Research Institute,Beijing 100083,China)
出处
《油气藏评价与开发》
CSCD
2021年第5期659-668,共10页
Petroleum Reservoir Evaluation and Development
基金
中国地质调查项目“重点地区构造体系及油气页岩气控藏条件调查”(DD20190085)。
关键词
天然气水合物
成藏条件
分布特征
南海地块
气源类型
natural gas hydrate
accumulation conditions
distribution characteristics
the South China Sea Block
type of gas source
