华北地区岩石圈热结构的研究

利用两种1°×1°平均大地热流资料,由观测资料和居里面反演得到的4种地壳岩石生热率模型,计算了华北地区(105°E-124°E,30°N-41°N)岩石圈的热结构. 定量的比较了各种模型的计算结果,选定了最佳模型. 莫霍面的温度大约在450-750℃之间变化,岩石圈底部深度在60-180 km变化,并发现大的构造断裂与热岩石圈底部的隆起相对应,MS＞6.5的地震大都发生在热岩石圈底部隆起区附近和莫霍面温度的高值区.

THERMAL STRUCTURE OF THE LITHOSPHERE IN NORTH CHINA

The thermal structure of the lithosphere in North China (105°E₁24°E, 30°N 41°N) was calculated using two kinds of average heat flow models and four heat production models which were obtained from observed heat production or from the inversion of Curie depth distribution. Analyses of the results and comparison of the depths of thermal lithosphere and the temperature of the Moho-discontinuity obtained by different models show that the 3rd heat production model is the best one. The temperature at Moho-discontinuity is about from 450℃ to 750℃ and is consistent with ones from other models in 80 percent of the whole area within the error of 15%. The depth of the thermal lithosphere bottom obtained by this model is about from 60 km to 180 km and is consistent with ones from other models in 70 percent of the whole area within the error of 15%. It is found that big fault systems are related to thinner parts of the lithosphere and the earthquakes of M S>6.5 occurred near the thinner parts of the lithosphere and the area in which the temperature of the Moho-discontinuity is higher.