地球深部流体演化与矿石成因

文中重点讨论含矿NaClH2 O溶液在从高温、高压向低温、低压条件改变时性质变化对矿石形成过程的影响。通过对含矿NaClH2 O溶液的实验观测获得对地球深部流体性质的新认识。地球深部的NaClH2 O流体大多处于超临界态流体 ,在上升过程中经减压降温后 ,通过临界态 ,进入低于临界态的热液状态。流体在这一跨越临界态的转变过程中造成了大多数矿石的沉淀。自然界里的许多矿石是在开放流动体系和在非平衡的化学动力学过程中形成的。开放流动体系矿物与水的反应动力学实验 ,证明一些矿石可能形成于流动热液。跨越临界态这一转变过程中的矿物水反应动力学实验结果表明了反应速率的大涨落。地球深部流体在上升过程中的性质演化、流动体系和非均相反应动力学是现代矿石成因研究的 3个关键问题

THE EVOLUTION OF DEEP EARTH FLUIDS AND ORE GENESIS

This paper focuses on the effects of the variation of the properties of ore\|forming NaCl\|H 2O fluids on the ore formation due to the changes of conditions from high temperatures and high pressures to low temperatures and low pressures.The experimental study of the ore\|forming NaCl\|H 2O fluids obtained a new message about the properties of deep earth fluids,by using hydrothermal diamond anvil cell.The deep earth fluids,even being of different salinities,may behave in a supercritical state.While the fluids rose up and temperatures and pressures decreased,they passed through the critical state and became hydrothermal solution below the critical state.The transition processes of the fluids crossing the critical state caused the ore precipitation.The ores always formed in an open system and in flowing fluids in nature,and also occurred in non\|equilibrium kinetic processes.The kinetic experiments of the mineral\|water interactions in an open system and in flowing fluids have provided evidences that the ore formation occurred in flowing fluids.The experiments that the fluids reacted with minerals during crossing the critical state,indicate that the reaction rates experience a large fluctuation.Therefore,the variations of the property of the deep earth fluids during rising up, the fluid flow systems and the reaction kinetics of water/rock interaction are the three key problems for the ore genesis.