Petrography, geochemical data and LA-ICP-MS zircon U-Pb dating have been obtained for Maokuishan monzogranites, Huangdi granodiorites and Chaoyang norite gabbro in Xiuyan area, eastern Liaoning Province. The major elements of Maokuishan mozogranites are high in Si, Al and K, and low in Fe, Mg, Ca and Ti. Trace elements are enriched in incompatible elements such as K, Rb, Th, and depleted in Sr, P, Eu, and Ti, geochemical features indicate that granitoids are aluminum A-type granites (A/CNK =0.98 similar to 1. 03, A/NK = 1. 11 similar to 1. 12). Huangdi granodiorite, with the content of SiO2 are 64. 1%-70.8%, K20/Na20 is 0. 87 1. 08, and the aluminium index are A/CNK = 0.98-1. 02, A/NK =1.31 similar to 1. 55, are enriched in LILEs, such as K, Rb, Sr and Ba, depleted in HFSEs as Nb, P and Ti, and high field strength elements, (La/Yb)(N) = 13. 41-68. 2, belong to metaluminousperaluminous I-type granitoids. Chaoyang norite gabbro with thecontent of SiO2 are 54. 8% 58. 3%, K2O/Na2O is 0. 57 similar to 0. 78, are enriched in LILEs, as K, Ba, Sr, and LREEs as La, Ce, Pr, Nd, depleted in HFSEs, as Nb, U, P, Ti. LA-ICP-MS zircon U-Pb age data of Maokuishan monzogranite, Huangdi granodiorite and Chaoyang norite gabbro are (137)Ma, (139)Ma and 139Ma, respectively, indicate that intrusive rocks were formed in Early Cretaceous. Combined with structure background graphic, Maokuishan monzogranites, Huangdi granodiorites and Chaoyang norite gabbro are all the products of magmatism in the extensional tectonic setting. Combined with spatial and temporal characteristics of the three plutons show in the Early Cretaceous period, Xiuyan area of eastern Liaoning Province in a non-orogenic extension environment, and the development of lithospheric thinning and stretching activities are characteristic from deep to shallow, is the eastern North China Plate stretch geodynamic setting concrete manifestation.
