2012年7月21日的一场强降雨使北京经历了一次严峻考验。气象台专家表示,此次暴雨覆盖华北地区北京雨势最大,是因为正好处于冷暖空......

Geochemical characteristics of the Neoproterozoic basic dykes widely exposed in the Wudang block of South Qinling show t......

Caledonian gold deposits are widely distributed in South China. They are developed in both South China Caledonian fold b......