摘要
以青海省天峻县木里地区天然气水合物发现区为研究对象,以天然气水合物发现井作为正演模型,采用250 m×500 m、100 m×100 m两种调查尺度,对陆地冻土区天然气水合物微生物地球化学烃检测技术的适用性进行了研究。结果显示:研究区有显著的微生物异常,指示下伏地层存在烃类富集;稀网格微生物调查查明烃类富集的有利区,而密网格调查很好地识别了天然气水合物分布的非均质性,与水合物钻探井所揭示的横向上天然气水合物分布不连续的特征一致。土壤吸附气的地球化学检测和分析,揭示研究区天然气水合物的气源十分复杂,主要为热成因的煤层气和油型气。研究结果为探索天然气水合物富集规律和勘探方向提供依据和参考。微生物地球化学勘查结果精细地刻画了冻土区天然气水合物分布规律及气源特征,结合地质学、地球物理、地球化学进行综合分析,为陆地天然气水合物的识别提供新的研究方法,同时降低天然气水合物的勘探风险,提高勘探的成功率。
The gas hydrate-discovering area in Muli of Tianjun, Qinghai Province was chosen as the research area, and the gas hydrate-discovering well was chosen as the analog model in this test to study the applicability of the microbial geochemical exploration （MGCE） method in gas hydrate exploration. Two different sampling grids of 250 m × 500 m and 100 m × 100 m were used in this study. The results showed that the research area had significant microbial anomaly, indicating the presence of hydrocarbon enrichment. The sparse grid study showed a favorable area of hydrocarbon enrichment, and the tight grid investigation showed the detail distribution of gas hydrate. This result verified the previous research result. The source of gas hydrates in the research area were also studied using geochemical method, and the results showed a very complex source, mainly thermogenic coal- bed gas and oil-formed gas. This microbial geochemical exploration result can describe the detailed characteristics of the gas hydrate distribution and gas sources. Using geomicrobial, geochemical, geology and geophysical analysis （ ‘ 4G＇ ） , it can provide a new research method for the identification of gas hydrates in permafrost, and reduce the exploration risk and improve the success rate of exploration.
出处
《现代地质》
CAS
CSCD
北大核心
2015年第5期1157-1163,共7页
Geoscience
基金
国家高新技术研究发展计划(2012AA061401)
神华青海能源开发有限责任公司项目"青海省天峻县聚乎更煤矿区三露天天然气水合物调查评价"项目(SHQHNY201307001)
