江汉盆地钻井地温测量和大地热流分布

盆地的稳态温度是分析地温场和大地热流的基础,是盆地构造热演化的必要前提。本文根据最新获得的9口钻井的稳态温度数据和124块岩石热导率,结合已有资料对江汉盆地地温梯度和大地热流进行了系统分析。结果显示江汉盆地热流41.9～60.9 mW/m~2,平均52.3mW/m~2,盆地总体表现为较低的大地热流,反映了中新生代以来构造活动逐渐减弱,盆地不断冷却的结果;从盆地内热流分布看,热流分布南高北低,反映了江汉盆地构造活动的不均一性。

Borehole temperature logging and terrestrial heat flow distribution in Jianghan Basin

Based on the newly obtained borehole steadY temperature data from 9 holes together with thermal conductivities of 124 core samples,we analyze the distribution of geotemperature and terrestrial heat flow in Jianghan Basin.The present temperature gradients vary from 28.36 to 39.32 ℃/km,lower temperature gradients is observed in the Cenozoic Basin margin and higher gradients are obtained in the Cenozoic Basin.The determined thermal conductivity values vary 41.9 to 60.9 mW/m~2,with a average of 52.3 mW/m~2.It shows that the influence of tectonothermal event before Cenozoic in Jianghan Basin has faded away,and the basin has cooled down.