Geochemistry of Rare Earth Elements of Mesozoic-Cenozoic Sandstones in North Margin of Dabie Mountai

• 作 者: 李双应 李任伟 岳书仓 刘因 王道轩 孟庆任 金福全
• 机 构: Department of Natural Resources and Environmental Science, Hefei University of Technology, Hefei 230
• 出 处: Journal of Rare Earths
• 发表日期: 2004年04期

Based on the study of REE in Mesozoic-Cenozoic sandstones, the paper indicates that Jurassic Fanghushan and Yuantongshan Formations and Lower Cretaceous Zhougongshan Formation have ∑REE of 157 μg·g~(-1), δ_(Eu) of 0.69 and (La/Yb)_N of 11.1, which are similar to the Foziling and Luzhenguan Groups, and it implies that the latter may be the source rocks of the former. The Sanjianpu and Heishidu Formations have high REE concentrations (∑REE=264.8 μg·g~(-1), 328.2 μg·g~(-1) respectively), high Eu anomaly (δ_(Eu)=0.57, 0.67 respectively) and lower Eu/Sm ratios (0.18～0.19), which differs from existent metamorphic rocks in the Dabie Mountains, so where their source rocks came from remains to be studied. The REE features of the Zhengyangguan Formation can be comparable to the Dabie complex and Luzhenguan Group, which shows that the Dabie complex had suffered unroofing in Neocene and constituted the source rocks. Mesozoic sandstones in Huainan area have lower REE concentrations (∑REE=80.9 μg·g~(-1)), high Eu anomaly (δ_(Eu)=0.66) and (La/Yb)_N of 5.7, and it indicates that their source rocks may not come from the Dabie Mountains.

Based on the study of REE in Mesozoic-Cenozoic sandstones, the paper indicates that Jurassic Fanghushan and Yuantongshan Formations and Lower Cretaceous Zhougongshan Formation have ΣREE of 157 μg · g -1, δ Eu (Eu) of 0.69 and (La / Yb) _N of 11.1, which are similar to the Foziling and Luzhenguan Groups, and it implies that the latter may be the source rocks of the former. The Sanjianpu and Heishidu Formations have high REE concentrations (ΣREE = 264.8 μg · g ~ ( (328.2 μg · g -1), high Eu anomaly (δ Eu (Eu) = 0.57, 0.67 respectively) and lower Eu / Sm ratios (0.18 ~ 0.19), which were derived from existent metamorphic rocks in the The REE features of the Zhengyangguan Formation can be comparable to the Dabie complex and Luzhenguan Group, which shows that the Dabie complex had been unroofing in Neocene and composed the source rocks. Mesozoic sandstones in Huainan area have lower REE concentrations ( ΣREE = 80.9 μg · g -1, high Eu anomaly δ_ (Eu) = 0.66) and (La / Yb) _N of 5.7, and it indicates that their source rocks may not come from the Dabie Mountains.