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The Lwandle Plate is one of three tectonic microplates, along with the Rovuma Plate and Victoria Plate, that make up the African Plate with the Somali Plate and the Nubian Plate. Its discovery is very recent, so the velocity of the plate is neither well known nor well understood. Many experiments are ongoing to quantify this. The Lwandle Plate lies between 30°E and 50°E, sharing a boundary with the Nubia, Somali and Antarctic Plates. The Lwandle Plate is largely oceanic, lying off the southeast coast of Africa. It is currently believed that the southern part of Madagascar forms part of the Lwandlean Plate, with one of the plate boundaries cutting through the island.〔〔〔 == Discovery of the Lwandle Plate == For many years it was widely accepted that rifting in the East African Rift system, 22–25 million years ago, resulted in the splitting of the African Plate into 2 smaller plates – the Somali Plate and the Nubian Plate. However, most recently, through the application of GPS technology and integration of earthquake data, it was discovered that the rift created three additional “micro-plates” plates – the Lwandle Plate, Victoria Plate, and Rovuma Plate.〔 Earthquakes occur most often at plate boundaries and have been used as a guide to predict the locations of multiple plate boundaries. “Lwandle’s” existence was postulated after studying earthquake data in areas that were once assumed to be the interiors of the Nubian and Somali plates. By including the Lwandlean Plate in their calculation, researchers were able to more accurately solve for the intersection between the East African Rift and the Southwest Indian Ridge. GPS technology and data was also introduced in an effort to show with certainty the difference between the Somali Plate and the Nubian Plate. Using the GPS data, researchers could measure the velocity of tectonic plates from their interiors. The existence of the Lwandle Plate was first quantified using the Lwandle-Antarctica-Nubia plate circuit closure constrained by spreading rates and transform azimuths along the Southwest Indian Ridge. Mathematical plate circuit closure is attained while including the existence of Lwandle; using plate circuit closure, plate velocities can be calculated from the velocities of other plates. In 2008, the entire East African Rift System was successfully "quantified" through the integration of the GPS and earthquake data with the spreading rate and transform azimuth constraints. There have been very few studies that directly study the Lwandlean Plate. Previous studies about Lwandle have primarily been focused on attempting to quantify the mechanics of the African Rift System.〔〔 For this reason, the presumed evolution and formation of the micro-plates are not well known. 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「Lwandle Plate」の詳細全文を読む スポンサード リンク
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