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Cambodia is a country in mainland South-east Asia, bordering Thailand, Laos, Vietnam, the Gulf of Thailand and covers a total area of . The country is situated in its entirety inside the tropical Indomalayan ecozone and the Indochina Time zone (ICT). Cambodia's main geographical features are the low lying Central Plain that includes the Tonlé Sap basin, the lower Mekong River flood-plains and the Bassac River plain surrounded by mountain ranges to the north, east, in the south-west and south. The central lowlands extend into Vietnam to the south-east. The south and south-west of the country constitute a long coast at the Gulf of Thailand, characterized by sizable mangrove marshes, peninsulas, sandy beaches and headlands and bays. Cambodia's territorial waters account for over 50 islands. The highest peak is Phnom Aural, sitting above sea level.〔 〕 The landmass is bisected by the Mekong river, which at is the longest river in Cambodia. After extensive rapids, turbulent sections and cataracts in Laos, the river enters the country at Stung Treng province, is predominantly calm and navigable during the entire year as it widens considerably in the lowlands. The Mekong's waters disperse into the surrounding wetlands of central Cambodia and strongly affect the seasonal nature of the Tonlé Sap lake. Two third of the country's population live in the lowlands, where the rich sediment deposited during the Mekong's annual flooding makes the agricultural lands highly fertile. As deforestation and over-exploitation affected Cambodia only in recent decades, forests, low mountain ranges and local eco-regions still retain much of their natural potential and although still home to the largest areas of contiguous and intact forests in mainland Southeast Asia, multiple serious environmental issues persist and accumulate, which are closely related to rapid population growth, uncontrolled globalization and inconsequent administration. The majority of the country lies within the Tropical savanna climate zone, as the coastal areas in the South and West receive noticeably more and steady rain before and during the wet season. These areas constitute the easternmost fringes of the south-west monsoon, determined to be inside the Tropical monsoon climate. Countrywide there are two seasons of relatively equal length, defined by varying precipitation as temperatures and humidity are generally high and steady throughout the entire year. ==Geological development== Southeast Asia consists of allochthonous continental blocks from Gondwanaland. These include the South China, Indochina, Sibumasu, and West Burma blocks, which amalgamated to form the Southeast Asian continent during the Paleozoic and Mesozoic periods. The current geological structure of South China and South-East Asia is determined to be the response to the "Indo-sinian" collision in South-East Asia during the Carboniferous. The Indo-Sinian orogeny was followed by extension of the Indo-Chinese block, the formation of rift basins and thermal subsidence during the early Triassic. The Indochina continental block, which is separated from the South China Block by the Jinshajiang-Ailaoshan Suture zone, is an amalgamation of the Viet-Lao, Khorat-Kontum, Uttaradit (UTD), and Chiang Mai-West Kachin terranes, all of which are separated by suture zones or ductile shear zones. The Khorat-Kontum terrane, which includes western Laos, Cambodia and southern Vietnam, consists of the Kontum metamorphic complex, Paleozoic shallow marine deposits, upper Permian arc volcanic rocks and Mesozoic terrigenous sedimentary rocks. The central plains consist mainly of Quaternary sands, loam and clay, as most of the northern mountain regions and the coastal region are largely composed of Cretaceous granite, Triassic stones and Jurassic sandstone formations. 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「Geography of Cambodia」の詳細全文を読む スポンサード リンク
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