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江苏省长江流域丘陵山区面积约9000平方公里,分岗地和丘陵两大地貌类型。岗地地势波状起伏,顶部相对平坦,一般地面高程10～60米(吴淞零点,下同),相对高度自数米至十余米不等。由第四系下蜀黄土组成的土质岗地分布较广,主要分布在镇江、南京、扬州市一带,堆积深厚,一般达10米以上。长期以来,由于不断受坡地径流的切割,形成纵横交错的冲沟,宽度自数十米至数百米不等,谷坡坡度一般5°～8°,最大可达15°。目前绝大部分的岗地地貌已形成岗、
Jiangsu Province, the Yangtze River valley hilly area of about 9000 square kilometers, sub-post and hilly two landform types. Topography of wavy ups and downs, the top is relatively flat, the general elevation of 10 to 60 meters (Wusong zero, the same below), the relative height from a few meters to more than ten meters. The Quaternary Xiashu loess is composed of a wide range of soil mounds, mainly distributed in Zhenjiang, Nanjing, Yangzhou area, the accumulation of deep, generally up to 10 meters above. For a long time, due to continuous cutting by slope runoff, criss-crossing gully was formed with the width varying from tens to hundreds of meters. The valley slope was generally 5 ° -8 ° and the maximum was 15 °. At present, the vast majority of posts and landforms have formed posts,