Basic features and significance of Yifeng-Dexing superimposition orogenic belt, Jiangxi Province

During the study and compilation of new generation of Jiangxi Regional Geology, the authors found a new kind of oro-genic belt type in the Yifeng-Dexing area, which is called Jinningian-Caledonian Yifeng-Dexing superimposition type orogenic belt that is spread in the semilunar tongue form. It is a concealed-semiconcealed type orogenic belt formed through N-S bidirection-al multi-periodic collision and superimposition. Based on studying and recovering the tense state, site state and phase state of the tectonic slices exposed along orogenic belts, the authors established a tectonic evolution sequence model with a three-layer structure. The model of structure includes the remnants of ophiolite of South China Sea, metamorphosed volcanic sedimentary series of forearc basin on the Yangtze continental margin in Middle-Late Proterozoic, abyssal facies sedimentary epimetamorphic rock slice of Lower Nanhua System, and Lower Nanhua System epimetamorphic rock slice of Late Qingbaikou Period-Early Paleozoic Period in Huaiyu-Guangfeng area. Yifeng-Dexing and Jingdezhen-Yiyang nappe zone on both sides of the orogenic belt is an important ore concentration area of copper, gold polymetallic resources, and the Late Paleozoic coal seam under metamorphic strata has a huge potential in search for coal.