热液流体泵吸上侵管流动力学模拟及其预测意义

地球流体相在各种地质过程中的行为和作用 ,是地球物质科学的核心课题。通过对山西义兴寨脉状金矿热液流体上侵动力学的模拟计算证明 ,构造泵吸驱动的矿液流动具有有压管流的性质 ,并探索引入柏努利方程对其流动状态进行描述。论证了地质流体因其性质和所处地质环境的不同 ,可划分为多孔介质中的渗流和较宽阔裂隙中的管流 (流动 )两种。赋存于地壳中深部或由岩浆冷却分异形成的成矿流体 ,在张剪性断裂活动中 ,主要由构造泵吸机制驱使其上侵成矿。热液在相对封闭 (未喷出地表 )的较宽阔的断裂系统中受应力驱动上侵流动 ,其性质接近于流体力学中的有压管流 ,可以用柏努利方程进行描述。推导出了描述热液管流上侵动力学特征的柏努利方程关系式 ,表明热液的流速与所处构造压力差、流体的性质 (温度和密度等 ) ,以及流动通道的结构特征有关。对义兴寨脉状金矿进行的计算结果证明 ,热液上侵流速场的空间变化与金矿化分布格局相吻合 ,流体的高流速地段指示含矿石英脉密集区 ,因此具有成矿预测意义。针对热液管流上侵过程建立的动力学总方程中 ,每一个变量都有明确的地质意义 ,并可以在矿区实际测量 ;绘制的几组理论关系曲线有助于具体分析各种地质和地球化学条件对成矿的控制作用。

DYNAMIC SIMULATION OF THE UPLIFTING PIPE FLOW OF HYDROTHERMAL FLUID BY TECTONIC PUMPING AND ITS PREDICTION SIGNIFICANCE

There are two kinds of the geologic fluid motion according to its tectonic environments and they are seepage flow in the porous media and pipe flow in the more wide fracture system The ore formation fluids from meddle deep parties of the Earth's crust or formed during magmatic cooling and differentiation uplift by the tectonic pumping mechanism of tension share fault activity This flux in fracture system drawing by tectonic stress is a pressured pipe flow, and may be described using Bernoulli's equation according to fluid mechanics It was developed a general dynamic equation for rising pipe flow of the hydrothermal fluid And from it that may be established that the rising flow velocity of hydrothermal solutions is controlled by tectonic pressure gradient, nature of fluids (temperature, density etc ) and the texture characters of flow canals Calculated results by using the general dynamic equation for Yixingzhai gold deposit demonstrate that flux velocity field distribution of hydrothermal uplifting has good identify with gold mineralization Therefore the pressured pipe flow modeling of hydrothermal fluid and its dynamic simulation have prediction significance