地热异常与地震活动关系的综合分析

根据地球内部热状况及震源热力学理论,分析了全球地热带与地震活动带之间的密切关系。指出我国1966年—1988年强震(Ms≥7.0)多发生在地热异常区的边缘(两端和两侧)及两个相近热区之间的地热梯度带。认为区域热流动态的分布特征是地震危险区的重要判别指标之一,与构造活动断裂有关的深井,温泉的温度变化可能是地热异常显示的灵敏“窗口”。     

MTS studies on the upper mantle conductivity in China

Based on the data from more than 200 MTS sites distributed within different areas of the Chinese continent, general characteristics of upper mantle conductivity have been described. At least two conductive layers have been found in the upper mantle of some areas. The first is thin with a resistivity of a modicum to few tens m; the second one is thicker with a resistivity of one to m. Nearly 300 heat-flow values indicate that there exists an exponential correspondent relationship between a depth of the upper mantle conductive layer with a thickness and an average value of heat flow. Based on the above results, the top depth map of this upper mantle conductive layer has been outlined for parts of the Chinese continent. This conductive layer is basically consistent with the low velocity zone in the upper mantle, and Cenozoic tectonism and current seismicity are significantly related to the variation of depth of the conductive layer in the upper mantle. The possible origins of the conductive layers in the upper mantle have been discussed here.     

冻土导热系数热流计法模拟试验及成果分析

导热系数表征物体内部较热部分向较冷部分传递热量的能力,冻土导热系数是冻土区天然温度场变化研究和土木建筑热工计算中的重要指标.介绍了冻土导热系数热流计法测试的仪器设备和试验方法,对取自大兴安岭多年冻土带的5种典型扰动土料,分别进行冻融两种状态下热流计法模拟试验.通过回归分析,得到估计这5种冻土导热系数的经验公式,同时分析...     

Surface temperature history determination from borehole measurements

All methods proposed to date for the determination of surface temperature history from temperature profiles measured in boreholes are based on the assumption that the borehole is a hole in a semiinfinite homogeneous earth of constant diffusivity , and more or less ignore the fact that the mathematical formulation for this problem is improperly posed. This assumption, which frequently represents a gross oversimplification of the situation, was originally introduced as a computational expedient. We propose a computational procedure which is independent of this assumption and takes the improperly posed nature of the problem into account. The essence of the method is: (a) determine the set of borehole profiles corresponding to a given set of linearly independent surface temperature history functions, and then (b) take the coefficients of the least-squares fit of these borehole profiles to the given borehole data as the coefficients in the linear combination of surface temperature history functions which defines the required approximation to the surface temperature history. An analogous procedure can be used to determine the lower boundary condition for the heat-flow problem if the surface-temperature history is assumed to be known. Results of numerical experimentation are used to indicate the extent to which the method is viable in practice.     

岩石圈下层塑性流动网带的剪切热效应

基于“网状塑性流动”大陆动力学模型和中国大陆大地热流的分布特征,文中针对网带黏性剪切热效应的平衡态,通过热力学能量方程的求解,导出网带温度异常方程等关系式,并通过与网带热流正异常的拟合分析,确定了相关的参数值。研究表明,塑性流动网带黏性剪切热的产生为温度的正异常提供了热源,并通过热传导扩展网带的影响范围,形成相应的热异常网带。作为对中东亚塑性流动网络系统平均状况的估计,网带的热异常宽度与地震带所显示的网带视宽度一致,约为65km;剪切网带的宽度为44km,约为网带热异常宽度的23;网带中线处的温度正异常约为210K,剪切网带边界处的温度正异常约为67K,至热异常带边缘处降低为零,其起伏形态与网带大地热流正异常“凸峰”相一致。文中为岩石圈下层塑性流动网络的存在及其对大地热流正异常分布的控制提供了理论依据     

Quantitative Expression of Heat Flow versus Tectonic Deformation in the China Continent： The Effects of Plastic-Flow Network and Stable Block

1 Introduction It has been understood in the study of terrestrial heat flow that the distribution of heat flow in the interior of continent is influenced by a large number of factors, involving heat sources (e.g. mantle heat flow, heat production of radioactive elements in the crust, magmatic activity, and heat production of tectonic deformation), heat transfercondition (e.g. thermal conductivity and thickness of media), groundwater circulation, etc. On the background of these factors it is pa…     

双探针型海底热流计数据解算模型选取

选取适合于双探针型海底热流计数据解算的简化模型,是双探针型海底热流计结构优化的理论基础,对提高海底热流数据解算精度具有重要意义。本文基于脉冲式双探针海底工作的有限元数值模型,对双探针的脉冲加热时间、体生热率、热物性、长度及半径等因素在双探针脉冲法的3个线热源简化模型中所引起的模型误差作了详细的分析和讨论,并以模型误差最小为原则选取简化模型。结果表明：1）脉冲加热有限长线热源（PFLS: pulsed finite line source）模型是双探针脉冲法中较为实用的简化模型,它可消除加热时间和探针长度对介质热物性参数求解的影响;2）在PFLS模型下,探针热导率对待测介质热物性测量的影响可以忽略;而探针间距越大、半径越小及其体积比热容与待测介质越接近,则所求介质热物性的模型误差就越小;在保证温度传感器能有效记录到温度变化的前提下,探针脉冲功率的大小基本不影响介质热物性求解的模型误差。