摘要
为了更好地分析地热资源的分布特征和富集规律,评价资源潜力,优选有利勘探开发目标,需要探索并形成一套满足各勘查阶段不同目的的分析思路和方法。借鉴油气地质分级分析与评价的经验,尝试性地提出了一套从全球构造到地热藏的地热单元分类分级评价的思路。以不同级次的构造单元为基础,根据勘查阶段与资料翔实程度,结合构造发育、地层结构、地热显示及地热资源分布的特点,将地热单元由大到小划分为地热域、地热区、地热带、地热系统和地热藏等5个级别。地热域是最大的地热单元,与全球范围内板块尺度的构造单元相对应,可进一步分为板缘地热域和板内地热域两种类型。地热区是地热域中的次级地热单元,主要的划分依据为区域构造特征,包括岩石圈结构、热体制等。地热带是地热区内根据地热显示强度和富集情况,结合造山带与盆地构造发育情况划分的三级地热单元。地热系统是相对独立的热能生成、运移、聚集和保持的自然系统,是地热资源勘探开发研究的重点。地热藏是一个相对完整且封闭的地热储盖组合,是商业性开发利用的具体对象。地热单元由大到小逐步细分,是地热资源认知过程中逐步聚焦的过程。不同层级的地热单元的地质认识与资源潜力的评价结果,对地热资源勘查与开发利用具有相应的指导作用。文中以西藏羊八井地热田为例,分别论述了其所属不同级次的地热单元类型。
In order to better analyze geothermal distribution pattern and enrichment rules, and evaluate geothermal resource potential for selecting favorable target areas of exploration and production, a set of strategies and analytical methods designed for each stage of geothermal exploration and production is greatly needed. Here, drawing on the experience of ranking and evaluating petroleum ＆ natural gas, a preliminary system of geothermal classification and ranking evaluation, from global tectonics to geothermal reservoir, is proposed tentatively. Based on the classification of ranks in tectonic unit, the geothermal unit can be divided into 5 ranks in descending order, namely realm, region, belt, system and reservoir according to exploration stage and accessible data, as well as tectonic activity, strata assemblage, geothermal manifestation and distribution. In this system, the geothermal realm is the largest unit, corresponding to global tectonic unit and can be subdivided into two types., the plate-boundary and plate-interior. Next, the geothermal region is the secondary unit in a geothermal realm distinguished by regional tectonics and structural geology, for instance lithospheric structure or thermal mechanism. Thirdly, the geothermal belt is the third level of the unit, partitioned by geothermal intensity ＆ enrichment manifestation and associated with structural geology development in orogen and basiru The geothermal system, the forth rank, is a relatively independent natural system involving geothermal generation, migration, accumulation and preservation, it is a key research area in geothermal exploration. And finally, the geothermal reservoir represents a suite of geothermal reservoirs and eaprocks in an intact and closed environment, it is the basic geological unit for commercial development and utilization. Division of geothermal unit in descending order represents a focusing process in geothermal resource cognition, in which evaluation assessment in geological and resource potentials of each rank guides each stage of geothermal exploration and production accordingly. In this paper, the Yangbajain geothermal field in Tibet, China was taken as a case study to illustrate the types of geothermal units in different ranks as classified according to the proposed system.
出处
《地学前缘》
EI
CAS
CSCD
北大核心
2017年第3期168-179,共12页
Earth Science Frontiers
基金
中国石油化工股份有限公司科技部项目(P13071)
国家自然科学基金联合基金项目(U1663209)
关键词
地热资源
地热单元
地热域-区-带-系统-藏
分级分类评价
羊八井地热田
geothermal resource
geothermal unit
geothermal realm-region-belt-system-reservoir
ranking and classification evaluation
Yangbajain geothermal field
