The geologic boundary between the northern part of the Socotra Basin and the Fukien-Reinan Massif, offshore Korea: Implementations in marine magnetics

Abstract

A detailed marine magnetic survey of the region southwest of Jeju Island, offshore Korea, reveals the boundary between the northern part of the Socotra Basin (SB) and the Fukien-Reinan Massif (FRM). To delineate the boundary and highlight its origin, several interpretation methods have been applied. Low and band pass filtering; upward-continuation filtering; horizontal gradient (HG) transformation and 2½D methods delineate the boundary in the subsurface basement. Analysis of the magnetic amplitudes through three selected profiles provides a good correlation between the applied methods and exposes the magnetic sources on and around the boundary. The modeling of magnetic anomalies northwest of the Socotra Basin revealed the edge lines between the adjacent subsurface geological units. Among the applied methods, the results of the horizontal gradient method were prominent in clarifying distinctly the location of this important boundary. These results are shown in addition to the results of other interpretation tools that the boundary is located in the shallow section of the northwestern part of the SB. Based on these results, FRM is probably sandwiched between two identified boundaries in the northwestern portion of the northern part of the SB. These results are consistent with earlier recent studies over the same area, and will lead to a better understanding of the geology of this neglected region and the East China Sea Shelf Basin in general.