Types, Characteristics, Causes and Control of Hydrocarbon of the Conduit Facies in the Volcanic Development Zone

Summary The volcanic reservoir exploration has become a focus. The conduit facies is an important part of volcanic structure. Combining 3D seismic data，drilling data，and field outcrops，we make comprehensive analysis of the conduit facies. There are two kind of conduit facies including the volcanic conduit and hydrothermal channel in the volcanic rock development zone. Though they are shown as the inverted cones，there are some differences in lithofacies and seismic facies. The volcanic conduit is mostly magmatic filling，and associated with a larger scale of high amplitude effusive facies. The volcanic conduit is characterized by “two strong and one weak” seismic features. The hydrothermal channel is filled with the surrounding rock debris. Its amplitude features is “one strong and one weak”. The volcanic conduit is formed by magma intrusion. The hydrothermal channel formation is controlled by the fluidization and disaggregation of rock at depth as a consequence of intrusive magma activity. The volcano conduit is beneficial to the development of cap rock，while the hydrothermal channel is beneficial to reservoir development. Based on the different hydrocarbon significance，the favorable exploration zone in the research area is pointed out.