摘要
By analyzing the forming conditions, phase control features and vertical development of this kind of mixed layer, and considering the developed features of fractured system, plain through-going of sedimentary facies and abrupt contact of lithology, the sedimentary body of the study area is obviously controlled by tectonic descent, intensity of source supply and volcanic eruption event. The gully-valley sedimentary system of volcanic and clastic rock is formed with the effect of 3 major controlling factors. Four sedimentary packing patterns of waterway type, dereliction type, intaking type and centre type in the isochronic framework develop in the gully-valley sedimentary system.