鲁北平原地温分布的特点及地热资源开发利用的前景

本文依据26口钻井的系统测温数据、1690个油层温度和21口自流热水井的资料,分析鲁两北平原地温场的特点和地下热水的赋存条件,提出地热田的基本模式,评述地区地下热水资源开发利用的前景。

THE CHARACTERISTICS OF THE GEOTEMPERATURE DISTRIBUTION AND THE PROSPECTS OF UTILIZATION OF GEOTHERMAL RESOURCES IN THE PLAIN OF NORTHERN SHANDONG PROVINCE

On the basis of the equilibrium temperature data measured in 26 holes, 1690 temperature measurements of oil-bearing layers, artesian flow rate and temperature logging data of 21 thermal water wells and the result of mathematical simulation of regional geothermal field, a review of the characteristics of geothermal pattern and the prospects of utilization of thermal water for the region studied are given in this paper.Main conclusions are as follows:(1)The northern plain of Shandong province geologically is a Mz + Cz basin of faulting-depression origin which developed on the Pre-Sinian and Paleozoic basement. The geothermal pattern is controlled by the structure condition. The configuration of isotherm reflects the regional tectonic trend(nearly EW, NE and NW)and rugged structure framework of the basement. The geotemperature distribution exhibits an alternating low-high-low pattern. Geo-thermal studies indicated that high temperature appears in subuplifts, whereas low temperatu-re-subdepressions. The geothermal gradient(G)of Cz sedimentary cover in subuplifts is about 4-5℃/100m and temperature at 2000m is 90-100℃; G in subdepressions is 3.2-3.5℃/100 m and temperature at 2000 m is 75-85℃. This phenomenon can be regarded as the result of redistribution of heat flow in upper-most part of the earth’s crust.(2)Jiyang Depression and Chengning Uplift are rich in low to medium thermal water resources. The total area of geothermal anomaly with grandient of higher than 4.0℃/100 m or 1.5 HFU amounts to 5900 km2. The buried depth of the main thermal water reservoir is usually about 1000-2000 m, The good condition of exploitation of thermal water is favorable for direct use of these resources for spaceheating, bathing, greenhouse etc..