库车前陆盆地大地热流分布特征

Terrestrial heat flow distribution in Kuqa foreland basin, Tarim, NW China

采集45块岩心样品进行热导率测试,在分析库车前陆盆地的地热场的基础上,通过温度和孔隙度的校正,获得原地热导率和地层热导率柱。根据热传导定理和热阻法计算热流值,获得了库车前陆盆地的52个大地热流值数据及其分布特征。库车前陆盆地整体属于低热流冷盆,各构造单元的大地热流值为40～50mW/m2,低于我国其他大、中型沉积盆地。山前带的热流值相对较高,如依奇克里克、大宛齐、克拉等构造分区的热流值均在45mW/m2以上,是冷盆中的高热流带,也是天然气高产出带;中央坳陷部位的热流值较低(小于45mW/m2);前缘隆起部位热流值较高,如塔北的提尔根;南部的热流值东高西低,如牙哈等地区的热流值均高于45mW/m2,而西部的羊塔克、英买地区的热流值低于40mW/m2。新生代,印度板块与欧亚板块碰撞的远距离效应使塔里木盆地和天山之间发生了强烈的盆山耦合过程,盆地边缘岩石圈挠曲和快速沉降,决定了盆地现今大地热流的分布特征。

Forty-five samples taken from 53 wells in the Kuqa foreland basin, north Tarim Basin, were selected for thermal conductivity measurement in laboratory, and the original thermal conductivity and formation thermal conductivity column were obtained based on the correction of temperature and porosity. Fifty-two heat flow values and their distribution were calculated based on the heat conduction theory and thermal resistance method. The Kuqa foreland basin is a low-heat-flow cold basin, the heat flow values of the tectonic units in the basin are 40-50 mW/m^2 , which are lower than that in other Chinese middle and large sized basins. The mountain front belt, including Yiqikelike, Dawanqi and Kela areas, has relatively high heat flow values and is the high heat also a high gas production zone. flow belt in the cold basin and In the south area, the heat flow decreases gradually from east to west. The heat flow distribution is determined by the lithosphere flexuring and fast subsiding during the Cenozoic tectonic evolution when intensive basin-mountain coupling occurred between Tarim Basin and Tianshan because of the far distance collision of the India and Eurasian Plates.