Geomorphic and geochemical evidence for the source of sand in the Algodones dunes, Colorado Desert, southeastern California
Geomorphic and geochemical evidence for the source of sand in the Algodones dunes, Colorado Desert, southeastern California
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DOI：
10.1007/978-94-009-0067-7_3
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发表时间：
1995
期刊：
影响因子：
2.9
通讯作者：
D. Muhs;C. Bush;Scott D. Cowherd;S. Mahan
中科院分区：
文献类型：
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作者：
D. Muhs;C. Bush;Scott D. Cowherd;S. Mahan
加州东南部的阿尔戈多内斯沙丘是美国最大的活动沙丘之一。Algodones沙丘的沙源是有争议的，在邻近的东梅萨地区稳定风成沙的来源还没有调查过。我们使用矿物成分和微量元素浓度，以确定这些活跃和稳定的沙丘最有可能的沙源。结果表明，冲积层来自圣贝纳迪诺山，进入索尔顿槽西北部的沙丘领域，冲积层来自巧克力山，这是立即沉积到东北部的沙丘，并没有出现显着的沉积物来源的Algodones和东梅萨沙丘。阿尔戈多内斯沙丘的活跃风成沙和东梅萨稳定风成沙可能都来自于古卡惠拉湖的沉积物，卡惠拉湖以前占据了索尔顿海槽的一部分，并在现在发现沙丘区的西部和西北部留下了桑迪海岸线沉积物。反过来，卡惠拉湖沉积物显然来自于科罗拉多河，当这条河改变了它的路线，流入索尔顿槽，而不是加州湾。
The Algodones dunes of southeastern California comprise one of the largest active dune fields in the United States. The source of sand of the Algodones dunes is controversial, and the source of stabilized aeolian sand in the adjacent East Mesa area has not been investigated at all. We used mineralogical compositions and trace element concentrations to ascertain the most likely source of sand for these active and stabilized dunes. Results indicate that alluvium derived from the San Bernardino Mountains, which enters the Salton trough to the northwest of the dune fields, and alluvium derived from the Chocolate Mountains, which is deposited immediately to the northeast of the dunes, do not appear to be significant sources of sediment for the Algodones and East Mesa dunes. Both active aeolian sand from the Algodones dunes and stabilized aeolian sand on East Mesa are probably derived from sediments of ancient Lake Cahuilla, which formerly occupied part of the Salton Trough and left sandy shoreline sediments to the west and northwest of where the dune fields are now found. Lake Cahuilla sediments, in turn, were apparently derived from the Colorado River, when the river shifted its course and emptied into the Salton Trough, rather than the Gulf of California.