The Distribution Of Volcanics And The Coupling Relationship With Deep Crust-mantle Structures In Songliao Basin

According to the deep reflect seismic data in north Songliao basin, Combine with crust structures and tectonic environment in the area, and abyssal structural mechanism, On the basis of characteristics of Crust-mantle, Analysis of relationship between crust-mantle reacte with magmatic activity.Volcanics not only is the deep earth material of ejecting earth Surface through crust ,but also is the direct evidence of crust-mantle reaction,Volcanic activities can reflect the history of formation and evolution of the basin . According to the previous people research about the age of volcanics and the contents of SiO2,Thus the author concluded that magma is from melting of crust and mantle,then magma change into native basalt by upper mantle, rise and invade into crust, because of invasion of high temperature basalt, lead to part of crust start melting, and become magmatic, at the same time magma mix and separate with basalt, Finally become neutral magma and rock. In songliao basin, Mesozoic volcanic deep activity process express early stage of magma activity in late Triassic and Middle Jurassic, mantle rise and gather into the bottom of the lithosphere and Moho uplift, Lithosphere start happening hot thinning. From Late Triassic to Early Cretaceous, because of mantle uplift, Subducted Oceanic crust and mixed ocean sediments lead to magma rise, Molten material spike along the Crustal weak zone or Previous Fracture diapir, and become Volcanic eruption on the surface. So volcanic in this area is the complex superimposed of thrust, rift and mantle uplift, at the same time and results exhibited characteristic of north-south compress in structure environment, east- west thrust, crust uplift and mantle thin, and wide volcanic range.Because composition and structure of volcanics are different from other rocks, volcanic showing specificity in response to the well logging and seismic. This article use the special nature of volcanic rocks to identify volcanic by various ways.In this area volcanic Widely distributed in Huoshiling and yingcheng, distribution of the volcanic obviously under control by Basement fault, Long-term activities of these faults provided a channel for the magma eruption, so volcanics generally distributed along the faults, Volcanic mainly distributed in the Low-lying in the west rift in huoshiling, Volcanic distributed more widely in yingcheng, in first and third section in yingcheng are all distribute.