梁山川上流의 段狀地形 = A Study on the Platforms-Morphology of the Upper Yang San River Area

다국어 초록 (Multilingual Abstract)

Along the upper Yangsan River banks, Platforms morphologically similar to river terraces.
The platforms which are located along the river banks in Korea are usually known as the river terraces.
But the majority of these platforms lack evidences that they have been formed by the rivers, even though they are found along the river banks, in the shape of platforms.
The purpose of this study formation of platforms-morphology and outcrops along the river sides.
The target areas of this study has following characteristics;
The slopes of this landform are changed as follows;rapid slope surface, gentle slope and platforms.
The platforms are located at the altitude of 30m∼140m, and large ones are found along the convex banks, and their slopes are 1°∼3°in gradient. The depth(thickness) of deposited materials are 5m to 7m, and become thin downward to the river.
As matrix, sands abound in the upper streams, silt and clay abound in the downstream.
The diameter of materials which are composed of deposits is along coarser in the upper stream, and becomes finer the downstream.
The roundness of rocks becomes very round toward the downstream.
The depth of weathering front becomes lower toward the downstream and it is 3m to 5m below platform surfaces.
All the baserocks are not the same level.
The deposit materials of these platforms originated from the back mountains.
Deposited materials are produced by congelifration and transported by massmovement of solifluction under periglacial environment, repetition of freeze-thaw.
The surface of gentle slope had been eroded by rainwash, especially sheet erosion.
The platforms are covered with a sliding materials.
And these materials have eroded the gentle slope and platforms at first.
The active erosion has resulted in formation of potholes, attrition of rocks and gradual lowering of the altitude of river beds in the direction of the upper stream.
These phenomena are especially conspicuous toward the headstream from the knickpoint located near Tongdo Hotel. Generally the platforms were formerly, last interglacial period, old river beds, and recently have been eroding down along the Yangsan fault line, because of lowering down of sea level.
The agency of platforms seems to be river terraces and climatic terraces. formed by river and climatic activities.

목차 (Table of Contents)

• Ⅰ. 序 論
• 1. 硏究目的
• 2. 硏究動向
• Ⅱ. 硏究方法
• Ⅲ. 硏究地域의 環境
• 1. 地質 및 地形槪觀
• 2. 段狀地의 露頭現象
• Ⅳ. 綜合考察
• Ⅴ. 結 論
• 參考文獻
• Summary