Subaerially exposed Holocene coral reef, Enriquillo Valley, Dominican Republic
Subaerially exposed Holocene coral reef, Enriquillo Valley, Dominican Republic
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多米尼加共和国恩里基略谷地下裸露的全新世珊瑚礁
DOI：
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发表时间：
1984
期刊：
影响因子：
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通讯作者：
R. Kulstad
中科院分区：
文献类型：
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作者：
P. Mann;F. Taylor;K. Burke;R. Kulstad
一处保存极为完好的全新世边缘珊瑚礁位于多米尼加共和国恩里基洛山谷中央边缘，平均海拔低于海平面5米。珊瑚礁记录了最新一次从东部进入85公里长、12公里宽的构造凹陷的海洋入侵，似乎代表了一种独特的保存。暴露在侵蚀沟壑中的珊瑚礁的极佳横截面揭示了现代加勒比海珊瑚礁的典型组成和分带，这些珊瑚礁存在于近海低能量环境中。放射性碳年龄测定(2)表明，生物礁的生长与上一次冰期(5930±100年至4760±90年)后海平面的上升相一致。三角洲沉积和活动断层崖上可能的垂直运动堵塞了山谷的东口，形成了拉戈恩里基洛湖，然后在干旱的气候下通过蒸发迅速降低了水位，在海平面以下40米处形成了盐湖∼。对山谷边缘岩石的地层学研究和盆地中心钻孔的数据表明，早在后中新世就有类似于这里描述的海洋入侵。
An extremely well-preserved Holocene fringing coral reef occurs at an average elevation of 5 m below sea level around the margins of the central Enriquillo Valley, Dominican Republic. The reef records the latest marine incursion from the east into an 85-km-long, 12-km-wide tectonic depression and appears to represent a unique preservation. Excellent cross sections of the reef exposed in erosional gullies reveal a composition and zonation typical of modern Caribbean reefs that are found in offshore low-energy environments. Radiocarbon age determinations (2) indicate that reef growth coincided with sea-level rise following the last ice age (5,930 ± 100 to 4,760 ± 90 yr B.P.). Deltaic deposition and possible vertical movements on active fault scarps dammed the eastern mouth of the valley and created Lago Enriquillo, the level of which was then rapidly lowered by evaporation in an arid climate to produce a saline lake ∼40 m below sea level. Stratigraphic studies of rocks along the valley edge and data from drill holes in the basin center indicate that there were earlier post-Miocene marine incursions similar to that described here.