摘要
浙东火山岩区水热型地热资源较为丰富,但热储类型以构造裂隙型带状为主,勘探风险大。具有针对性的有利区评价方法是降低研究区地热勘探风险的有效途径。本文在系统梳理研究区地热成矿规律的基础上,提出一种基于层次分析法和综合指数法的评价体系,即将研究区网格化,对选定的评价指标进行权重赋值和专家打分,使各项指标的好坏程度相对标准化、定量化,继而对每个网格的所有因子进行加权平均,计算综合指数,评估不同区块的条件好坏。该方法从地热的“储、盖、通、源”四大属性层入手,考虑主要控矿因素和指示标志,选定了“地层岩性”“断裂的年龄”“断裂规模和性质”“大地热流值”“地震密度”“矿点类型及规模”“基岩裂隙泉流量”等7个评价指标,充分利用GIS平台的计算分析能力对研究区进行了半定量的分区评价,划分出成矿重点区、成矿远景区以及成矿不利区,为后期研究区地热勘查及政府规划提供科学可靠的依据。评价结果在宁波地区水热型地热勘查中得到应用和验证,大大降低了地热勘查的风险。
Eastern Zhejiang is rich in hydrothermal geothermal resources,but the thermal reservoir type is mainly zonal or veined controlled by regional faults,with high exploration risk and low success rate.Targeted favorable area evaluation method is an effective way to reduce the risk of geothermal exploration in the study area.On the basis of systematically combing with the geothermal metallogenic law of the study area,this study puts forward an evaluation system based on analytic hierarchy process and comprehensive index method,which the study area is gridded,and the selected evaluation indexes are assigned by weights and scored.This study makes the quality of each index relatively standardized and quantitative,and then carries on the weighted average of all the factors of each grid,calculates the comprehensive index,and evaluates the conditions of different blocks.This method starts with the four attribute layers of geothermal"reservoir","cover","communication"and"source",and considers the main ore-controlling factors and indication marks.Seven evaluation indexes such as"stratigraphic lithology","fault age","fault scale and property","geothermal heat flow value","seismic density","ore site type and scale"and"bedrock fissure spring flow"are selected.Make full use of the calculation and analytic ability of the GIS platform to make a semi-quantitative zoning evaluation of the study area,and divided into metallogenic key areas,metallogenic prospect areas and metallogenic unfavorable areas,which provides a scientific and reliable basis for geothermal exploration and government planning in the later study area.The evaluation results have been applied and verified in hydrothermal geothermal exploration in Ningbo area,which greatly reduces the risk of geothermal exploration.
作者
吕清
毛官辉
郑敏
柳永胜
彭鹏
韦毅
陈俊兵
LV Qing;MAO Guanhui;ZHENG Min;LIU Yongsheng;PENG Peng;WEI Yi;CHEN Junbing(Zhejiang Hydrogeological Engineering Geological Brigade,Ningbo,Zhejiang,315012;Zhejiang Engineering Survey and Design Institute Group Co.,Ltd.,Ningbo,Zhejiang,315012)
出处
《浙江国土资源》
2023年第S1期41-51,共11页
Zhejiang Land & Resources
关键词
水热型地热资源
控矿因素
指示标志
AHP
综合指数法
成矿有利区
Hydrothermal-type geothermal resources
ore-controlling factors
indicator
AHP
comprehensive index method
metallogenic favorable area
