CONSIDERATIONS ON DETERMINATION OF THE DEPTH OF GEOLOGICAL PROCESSES

The method sofar adopted to determine the depth where geological processes occur is to divide the pressure by specific weight (density) of rocks. This method is correct only when the rocks are assumed to be hydrosatic. Actually,rocks from the shallow crust to the deep mantle,are not ideally hydrosatic,and the viscosity coefficient of them is known to increase gradually with depth.Also,stress measurements show that horizontal compressive stress is usually greater than vertical stress at some depth,indicating the important role of tectonic force in the stress state of rocks. It is worthy of note that Lu et al(1998)proposed a method for measuring the depth where some geological processes occurred.