Landform development in the Geumsan and Geumosan reflects the tectonic movements and weathering patterns observed on the southern coast of the Korean Peninsula. Major tectonic movements acted in three differnet directions at different periods: ① northeast-southwest, ② south-north, and ③ eastwest directions. Consequently, the tectonic movements have arranged the landform of the mountain ranges along these directions. Specific landforms from the tectonic processes varied depending on the patterns of rock weathering. For example granodiorite developed a high density of horizontal joints due to its internal gneissosity. This structural characteristic caused the formation of plate-like rock debris and the development of large-scale block stream and talus in the region. By contrast, granite, a similar rock to the Jurassic Daebo granites of the central region, primarily formed exposed rock masses with both vertical and horizontal joints. Typically, this type of rock is characterized by sandy-grained weathering materials on the surface as a result of granular disintegration, which are currently deposited and formed sandy beaches on the coast. Granite contains weathering-resistant minerals, and it is closely associated with sandy sedimentary topography (sandgravel bar, sandy beaches) due to its lithologic characteristic.