摘要
大地热流是揭示一个地区的温度空间展布、地热资源形成和赋存条件的综合性评价指标。川东地区大地热流的研究十分薄弱,制约着对该地区地热资源潜力及展布的认识。本文首先利用4口钻井178个系统稳态测温数据和25口钻井76个试油温度数据,计算得到了川东地区的地温梯度和大地热流,再利用一维稳态热传导方程计算得到川东地区下二叠统栖霞—茅口组热储的地温,最后明确栖霞—茅口组发育的地热资源类型及潜力。结果表明:川东地区地温梯度在16.0~21.3°C/km之间,平均为(18.3±1.59)°C/km;大地热流值在44.3~67.7 mW/m^(2)之间,平均为(55.5±6.0)mW/m^(2),具有构造稳定区的低温型地温场特征。栖霞—茅口组是川东地区最重要的热储,主要发育中-低温型地热资源,其中,低温型地热资源主要发育在西南构造分区;中温型地热资源主要发育在东南构造分区、东北构造分区及西北构造分区。结合热储特征,可以得出川东地区栖霞—茅口组具有形成丰富地热资源的热储和地温条件。该成果可为川东地区的地热资源勘探评价提供重要的地热信息。
Terrestrial heat flow is a comprehensive index that reveals the spatial distribution of temperature and the formation and occurrence conditions of geothermal resources in a region.The terrestrial heat flow in the Eastern Sichuan Basin has not been extensively studied,which restricts the understanding of the potential and distribution of geothermal resources in this area.In this study,the geothermal gradient and terrestrial heat flow in the Eastern Sichuan Basin are calculated using steady-state temperature measurement data of 178 systems in 4 wells and 76 formation-testing temperature data in 25 wells.Thereafter,the geotemperature of the Lower Permian Qixia–Maokou Formation thermal reservoir in the Eastern Sichuan Basin is calculated using the one-dimensional steady-state heat conduction equation.Finally,the types and potential of geothermal resources developed in the Qixia–Maokou Formation are obtained.The results show that the geothermal gradient in Eastern Sichuan Basin ranges from 16.0 to 21.3°C/km,with an average value of(18.3±1.59)°C/km,and the terrestrial heat flow ranges from 44.3 to 67.7 mW/m^(2),with an average value of(55.5±6.0)mW/m^(2),which has the characteristics of a low-temperature geothermal field in the tectonic stable area.The Qixia-Maokou Formation is the most important thermal reservoirs in Eastern Sichuan Basin.It mainly develops medium-low temperature geothermal resources.Among them,low-temperature geothermal resources are mainly developed in the southwest structural zone,while medium-temperature geothermal resources are mainly distributed in the southeast,northeast,and northwest structural zones.Combined with the characteristics of thermal reservoirs,it can be concluded that the Qixia-Maokou Formation has the thermal reservoir and geothermal temperature conditions necessary to form rich geothermal resources.The results may provide important geothermal information for the exploration and evaluation of geothermal resources in this area.
作者
兰镭
左银辉
冯仁朋
蔡家兰
杨梅华
徐文礼
徐姁
LAN Lei;ZUO Yin-hui;FENG Ren-peng;CAI Jia-lan;YANG Mei-hua;XU Wen-li;XU Xu(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu,Sichuan 610059;Chongqing Gas Mine,Southwest Oil&Gas Field Company of PetroChina,Chongqing 400707)
出处
《地球学报》
CAS
CSCD
北大核心
2023年第1期169-179,共11页
Acta Geoscientica Sinica
基金
成都理工大学珠峰科学研究计划(编号:80000-2021ZF11415)
国家自然科学基金项目(编号:41972109)联合资助。
关键词
川东地区
地温梯度
大地热流
热储
地热资源
Eastern Sichuan Basin
geothermal gradient
terrestrial heat flow
thermal reservoir
geothermal resource