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Paleo Kathmandu Lake is the former lake (or lakes) which lied where Kathmandu Valley is today. Similar to the situation of Mexico City and Pokhara Valley, the valley where the lake once stood is densely populated, and highly vulnerable to both nearby and even distant earthquakes due to liquefaction and amplification of waves because of unsettled clay soil, specifically here called ''kalimata''. The valley has the world's worst quake risk.〔http://www.myrepublica.com/portal/index.php?action=news_details&news_id=67731〕 ==Geology== The valley is filled by thick lacustrine and fluvial deposits, more than 550 m thick, which is Pliocene to Pleistocene in age. The valley has a maximum 500 – 550 meter thickness of unconsolidated sediment in the central part. The quaternary sedimentary history is consistent with two major sedimentary stages. The lower fluviatile stage consisting of 200–250 m thick granular sediment is overlain by lacustrine sedimentary stage of 200-300m section of clay sediment. This sedimentary scenario existing in central part of the basin transitions into fluviatile facies in the northern part of the valley. Southern part is characterized by fluviatile and proximal lacustrine deposit.〔http://www.iitk.ac.in/nicee/wcee/article/2106.pdf〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Paleo Kathmandu Lake」の詳細全文を読む スポンサード リンク
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