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Xiuyan crater, China: Impact origin confirmed

Authors:
  • Guangzhou Institute of Geochemistry Chinese Academy of Sciences

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The well-preserved 1.8-km-diameter Xiuyan crater is located in the low mountain-hill region of the northern part of Liaodong Peninsula of northern China. Recently, a 307-m-deep borehole at the centre of crater became available. After penetrating 107 m lacustrine sediments, a breccia lens about 188 m in thickness was encountered. The crater-fill breccia is deposits of rock clasts and fragments more or less shock-metamorphosed. The features of geological structure and stratigraphic configuration within the crater, shock-melted rocks, and PDFs in quartz found in the basement rocks close to the crater rim and in the crater-fill breccia provide clear evidence for an impact origin of the Xiuyan crater. KeywordsXiuyan crater-shock metamorphism-breccia-PDFs-glass
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... The rim crest and both sides of rim are mostly covered with weathering soil, eluvial and diluvial deposits up to several meters thick. A few spots with exposed basement rocks (mainly leucoleptite) emerge from the rim walls (Chen et al., 2010). The crater floor is covered with Quaternary lacustrine sediments, with organic-rich lacustrine sediments in the upper part and loose brecciated rock debris and shock breccia accumulation in the lower part. ...
... In the numerical simulation using the SEM, to ensure the accuracy of the simulation results, it is required that at least five Gauss-Lobatto-Legendre integration points be contained in each The sketch of geological profile of Luoquanli basin (Chen et al., 2010). ...
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Chapter
The Xiuyan structure is a well-preserved simple bowl-shaped crater in the northern part of the Liaodong Peninsula of northern China.
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