| The Tan-Lu fault zone experienced the strike-slip movement from the latest late Jurassic to the early Cretaceous, the extensional movement from the late Cretaceous to Paleogene, and post-Eogene compressive activities since Mesozoic. Three stages of Meso-Cenozoic evolution in the Tan-Lu fault zone were all associated with magmatic activities. The scale of magmatic activities, lithology, petrochemistry and geochemistry of igneous rocks are different in three stages. These features are not only relative to the origin of magma, but also to the evolution and deep processes of the fault zone.This paper obtained 40ArI39Ar ages for the strike-slip mylonites from the middle-southern segment of the Tan-Lu fault zone with varying l2OMa to 132Ma. These ages represent the cooling age of the ductile left-lateral strike-slip deformation on the Tan-Lu fault zone. Evidence above indicates that the Tan-Lu large-scale left-lateral wrench occurred in the early Cretaceous. 40Ar/39Ar ages of the Wawuliu and Wawuxue rock mass for biotite along the Tan-Lu fault zone intrusion in the northern segment of the Zhangbaling uplift zone are 127.87 ?0.46Ma and 120.00 ?0.5OMa respectively. K-Ar whole-rock ages for volcanic rocks from the Longshan抯 area, Feidong and the Daotuo抯 area, Yishui are 119.2 ?.3Ma and 114.8?1.OMa respectively, belonging to the early Cretaceous not the late Jurassic. Their isotopic ages coincide with the deformed time of the strike-slip mylonites in the Tan-Lu fault zone, and reflect that the strike-slip movement of the Tan-Lu fault zone induced the early Cretaceous magmatic activities, not the results of the riftogenesis. It is further proved that the large-scale wrench movement of the Tan-Lu fault zone took place mainly in the early Cretaceous.Mesozoic igneous rocks in the middle-southern segment of the Tan-Lu fault zone appeared a set of intermediates rocks characterized by rich in alkali, potassium, belonging to high-K calc-alkaline series and shshonitic series, and notably rich in highly incompatible lithophile element, such as Rb, Th, Ba, LREE. The Tan-Lu fault zone controls the area抯 magmatic activities. K~ values are more than 1, Nb~ values are less than 1. It is suggested that the mother magma not only included mantle-derived information but also the crust-derived information. Investigation results including isotope and the mantle-derived xenoliths show that these magmatic activities during the later of the strike-slip stage originated from the transitional zone? ?(1Ubetween the crust and mantle, and also demonstrate that the fault zone had cut into the boundary of the crust and mantle. Just under this setting of oblique subduction of the Izanagi Plate, the eastern China continent suffered from regional compression and shearing. Therefore, the eastern China continent experienced lithospheric thinning and a series of NE-NNE sinistral strike-slip fault system, caused a large-scale magmatic activities.The extensional activities, along the Tan-Lu fault zone occurred in the late Cretaceous to Paleogene, resulting in development of a series of extensional basins along the fault zone and a set of Paleogene subalicalic theoletite with higher LREE. Sr, Nd isotopes suggest magmas origin from the enriched-mantle. Rare element features show the mother magma area experienced the partial melting and the mantle metasomatisni. Paleogene magma eruptions from the middle-southern segment of the Tan-Lu fault zone have the same geodynamic setting as a lot of other contemporaneous basins in East China. They were all developed under lithosphere arching in East China due to high-angle, westward, perpendicular subduction of the Pacific Plate. Under this settings of asthenosphere upwelling and lithosphere delamination and thinning, led to the first basalt eruption in the Tan-Lu fault zone.With becoming more and more young of the post-Eogene basalt from the middle-southern segment of the Tan-Lu fault zone, their alkali, the fractional degree of LREE/I-IREE and incompatible element enrichme...
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