Deep Structure and Ore-forming in Lujiang-Zongyang OreConcentrated Area
庐江-枞阳矿集区深部结构与成矿

In order to explore the deep structure and crustal frame of Lujiang-Zongyang iron and sulfur ore con-centrated area and volcanic basin in middle-lower Yangtze valley metallogenic belt during Cretaceous, and discuss deep metallogenic control conditions. We finished deep reflection seismic profile through volcanic basin (recorded 30 s) and shallow high resolution reflection seismic profile in Luohe iron diggings and discovered whole fine crustal structure, surveyed regional structure and stress field characteristics simultaneously, and obtained latest Cognition. It was confirmed that the ear-shape Luzong basin was a dissymmetrical basin along Luohe fault with north-east strike direction and eliminated the judgment that another half basin was buried, below red layer, west side of Luohe fault. The Luohe fault was a deep fault which cut through MOHO, the dip was south-east, and it also was the surging and eruption channel of magma and mantle fluid; we also identified multi-layer interfaces, the thickness of the volcanic rocks and sandstones was ca. 4-5 km (the thickness of volcanic rocks was ca. 3 km), the depth of deformation bottom layer from Triassic to Sinian was ca. 18-20 km, the metamorphic basement formed middle and lower crust, the dip of MOHO surface was north-west, depth was ca. 33-31 km; the deep occurrence of Tanlu fault was steep and cut through MOHO, width was ca. 10 km.