太湖地区,包括江苏省南部茅山以东,宜溧山地以北,浙江省的杭嘉湖平原及上海市的部分地区。在地质构造上,太湖地区处于江南古陆的东北端,中生代末期,由于强烈的构造运动,产生了上海、阳澄湖、太湖、常州几个断陷盆地。新生代以来,由于该区断续的下沉,在几个盆地内填满了第三纪、第四纪的沉积物。今日的太湖即位于古太湖构造盆地里。它是发育于冲积平原上的宽浅型构造湖。晚更新世玉木冰期,气候寒冷,海面下降,在太湖平原上沉积了一层黄褐色、棕黄色、暗绿色粉砂质亚粘土(即下蜀粘土),在区内形成由西南向东北倾斜的地面。根据太湖地区全新世以来的沉积物、动植物化石(亚化石)、泥炭层、古文化遗址,特别是气候变化等分析,全新世的古地理环境演变可分为:早全新世(距今10,000～7500年),中伞新世(距今7500～2500年),晚全新世(距今2500～现在)。

Based on sediments,fossils,cultural remains and peat layer,three phrases of the palaeogeographyic change of tbe Tai Hu region can be distinguished:early Holocene (about 10000 B.P-7500 B.P),middle Holocene (7500 B. P-2500 B.P),late Holocene (2500 B.P to present). In the early Holocene when the climate was cold and dry,yellow,grey silt-clay and subclay had been covered on the depressions and plains in the region,the vegetation consistes of deciducous broad-leaved and coniferous mixedforests and steppes. In the middle Holocene when the climate became hot and humid,and the sea level rose to present sea level,the Tai Hu Lake formed.Lacustrine deposit of grey clay and peat were found widely in the region.In Neolithic age man started to settle on the hills of this region.In that time,the vegetation mainly consisted of evergreen broad leaved forests. In the late Holocene when the climate turned to warm and moist,the Tai Hu Lake was expanded,with Yangcheng Hu,Cheng Hu and Dianshan Hu being formed one after another.A alluvial-lacustrine plain with a dense network of river and lake took shape in this region,The vegetation mainly consisted of coniferous mixed forest and hydrophyte such as Potamogetom Sp., Sphagnum Sp.widely grew.