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红水河流域岩溶浸没内涝灾害形成的地学因素分析 被引量:7
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作者 郭纯青 李文兴 《中国岩溶》 CAS CSCD 1999年第3期228-233,共6页
红水河流域由于多年人类活动和水能资源开发所产生的岩溶浸没—内涝灾害,在局部范围内比较严重,必须引起高度重视! 据红水河梯级开发与规划电站的修建情况,对红水河干流岩溶区内已发生的浸没—内涝灾害成因,进行了综合分析。
关键词 红水河流域 岩溶浸没 内涝灾害 地学因素
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洞庭湖区洪涝灾害的地学因素与人为因素 被引量:4
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作者 贺建林 《灾害学》 CSCD 2000年第4期43-48,共6页
从地学因素与人为因素两个方面分析了近 10年来洞庭湖区的洪涝灾害。
关键词 洪水 水灾 地学因素 人为因素 洞庭湖区
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四川盆地低产土壤的地学因素
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作者 徐亚莉 《西南大学学报(自然科学版)》 CAS CSCD 1993年第3期22-26,共5页
本文根据地学观点阐明四川盆地低产土壤分布规律、形成原因与地质、地貌、水文等因素的关系,并提出治理地学障碍因子的措施。
关键词 低产土壤 地质环境 地形 水文地质条件 四川盆地/地学因素
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Genesis of Qujiashan manganese deposit, Shaanxi Province: constraints from geological, geochemical, and carbon and oxygen isotopic evidences 被引量:3
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作者 WANG Zi-yong HAN Run-sheng +2 位作者 REN Tao WU Yong-tao LI Hu-jie 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第12期3516-3533,共18页
The Qujiashan manganese deposit is located in the Longmen-Daba fold belt along the northern margin of the Yangtze Block. The layered ore bodies are distributed within the purple-red calcareous shale. Qujiashan is a hi... The Qujiashan manganese deposit is located in the Longmen-Daba fold belt along the northern margin of the Yangtze Block. The layered ore bodies are distributed within the purple-red calcareous shale. Qujiashan is a high-grade w(MnO)=8.92% to 18.76%) manganese deposit with low-phosphorus w(P2O5)=0.08% to 0.16%) content. It also has a low total REEs contents(with an average of 101.3×10-6), and has inconspicuous Ce(0.81 to 1.29) and Eu(1.00 to 1.25) anomalies. lg(Ce/Ce*) values are from-0.02 to 0.11. The ores have high SiO2/Al2O3 and Al/(Al + Fe + Mn) ratios. In figures of Fe–Mn–[(Ni+Cu+Co)×10] and lgU–lgTh, all samples show that hydrothermal exhalative fluids played an important role during mineralisation. The δ13CPDB and δ18OSMOW values of eight ore samples are from-20.7‰ to-8.2‰(with an average of-12.4‰) and from 14.3‰ to 18.7‰(with an average of 17.0‰), respectively. These carbon and oxygen isotopic features indicate that hydrothermal fluids derived from deep earth are participation in the metallogenic process, which is also supported by high paleo-seawater temperatures varying from 47.08 to 73.98 °C. Therefore, the geological and geochemical evidences show that the Qujiashan deposit formed from submarine exhalative hydrothermal sedimentation. 展开更多
关键词 manganese deposit element geochemistry carbon and oxygen isotopes GENESIS Qujiashan manganese deposit
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