A QUANTITATIVE MODEL OF HEAT PRODUCTION BY FAULTING AND ITS EFFECT ON THERMAL EVOLUTION OF HYDROCARBON SOURCE ROCKS

A quantitative heat-producing model of faulting was constructed proceeding from the basin stress state analysis and from the viewpoint of frictional heat production.On the basis of the model,the quantitative relationships between the heat quantity produced by fault plane friction and the fault nature,depth,tectonic stress and fluid pressure were established,and the effects of heat produced by fault plane friction on the thermal evolution of hydrocarbon source rocks were analyzed quantitatively under earthquake conditions.The results show that:the fault depth,tectonic stress,fluid pressure,fault displacement,friction coefficient on fault planes are decisive factors of heat quantity produced by faulting;the rate of fault movement has nothing to do with the cumulative heat quantity produced by fault friction,but it is a key factor of the temperatures on the fault plane;under the conditions of a high rate of fault movement(e.g.earthquake type),very high temperatures may be produced by fault friction,which can cause partial melting of rocks near fault planes but the scope and lasting time of its influence on the thermal evolution of rocks are very limited.