Shatsky Rise Structure Analysis And It's Formation History Discussion

Shatsky Rise, which located in Northwest Pacific Ocean, is the main research area of Integrated Ocean Drilling Program Expedition 324. This famous giant ocean plateau, which formed during magnetic converting time, located in an ridge-ridge-ridge area. There are several theories to explain this plateau formation mechanism, among which spreading ridge reorganizations and mantle plume theories are the most well accepted. The Previous research suggests that the formation of the rise may have some relationship with ridge or plume. IODP Expedition 324 is carried out to investigate the rise in more detail and better understand the formation mechanism of this plateau. The fact that existing data can be interpreted both mechanisms suggests that this plateau is uniquetly suited for testing plume head versus ridge tectonics models.Because several, perhaps many, oceanic plateaus formed at triple junctions, Shatsky Rise probably represents a significant class of ocean plateau, if indeed it is not representative of all. So it become very important to research the formation mechanism of shatsky rise.People have do some research before,but because it is hard sample,so still short of sampling and certification. So IODP do Expedition 324 plan and want further know the formation reason of Shatsky Rise.The FMS(Formation Microscanner Service)data used in this paper was obtained from IODP expedition 324.After process and interpretation, the FMS data are explained combine with magnetic lineation, seismic and coring description. As an advanced logging technology,FMS has been used in recovery of original dip direction of structural elements, and that of sedimentary beddings for its high resolution and intuition.Interpretations of geological structures and their dip directions are discussed in this paper with the FMS information of three holes which include U1347A, U1348A and U1349A.The FMS data shows that the formation of the TAMU Massif is consistent with the seafloor spreading theory while the formation of the Ori Massif has no obvious preferred stress field, being deduced to be related to a mantle plume head.Several parts are included in this paper. First is the general geological settings of Shatsky research area followed by the theory of FMS and dip recovery. The data which include magnetic lineation, the description of core's structure and composition, units of stratum, and FMS data are exhibited. FMS processing software and processing procedure are descript as an important chapter.The conclusion is drawn based on the FMS data and the Previous research in the end.