华北地台岩石放射性元素与现代大陆岩石圈热结构和温度分布

在华北地台1.4×106km2的范围内系统采集了12193个岩石样，组合成1207件分析样，对放射性产热元素K，Th，U进行了测试，同时由国家一级岩石地球化学标准物质监控分析质量．根据岩石中K，Th，U的含量和地壳各结构层的岩石组成，计算了地壳各壳层放射性产热元素的含量，系统研究了华北地台岩石与各时代地层的平均热产生率及其变化，并建立了华北地台现代大陆岩石圈的热结构和温度分布．应用一维稳志热传导模型，求得了华北地台岩石圈的深度-平均地温分布曲线．地表热流密度分布和岩石圈深度-地温分布曲线研究表明，现今华北地台壳内熔融作用不明显。与世界上其他大的稳定克拉通区相比，华北地台地壳活动性较大，具有准地台的特点．

RADIOACTIVE ELEMENTS OF ROCKS IN NORTH CHINA PLATFORM AND THE THERMAL STRUCTURE AND TEMPERATURE DISTRIBUTION OF THE MODERN CONTINENTAL LITHOSPHERE

In a total area of 1.4 ×106 km2 in North China Platform （NCP）, 12193 rock samples were systematically collected and combined into 1207 composite samples.Heat-producing elements K. Th and U were analyzed by XRF or using national primary geochemical certified reference materials of rocks for data quality monitoring. Based on the contents of K. Th and U in rocks and rock composition of the crustal layers, the contents of K. Th and U in crustal layers are calculated. The heat production of rocks and the strata of various ages in NCP are studied. The thermal structure and temperature distribution of modern continental lithosphere in NCP has been established. With the one-dimensional steady-state thermal conduction model,the depth-temperature distribution curve of the current continental lithosphere in NCP is given .In this study the authors indicate that the crustal melting of the current continental lithosphere in NCP is not obvious from surface heat flow and depth-temperature curve. Compared with other great stable craton regions, there is greater crustal activity of NCP which has paraplatformal characteristics.