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On the basis of actual analytical data of 767 composited samples collected mainly from about 750 large to middle representative granitoid bodies all over China, the average chemical compositions and element abundances of about 70 chemical elements of SiO2, Al2O3, Fe2O3, FeO, MgO, CaO, Na2O, K2O, H2O+, CO2, TFe2O3, Ag, As, Au, B, Ba, Be, Bi, Cd, Cl, Co, Cr, Cs, Cu, F, Ga, Ge, Hf, Hg, Li, Mn, Mo, Nb, Ni, P, Pb, Rb, S, Sb, Sc, Se, Sn, Sr, Ta, Th, Ti, Tl, U, V, W, Zn, Zr, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y in alkalifeldspar granite, syenogranite and adamellite in 7 geotectonic units in China such as Tianshan-Xing’an orogenic series, Sino-Korean metaplatform, Kunlun-Qilian-Qinling orogenic series, Yunnan-Tibet orogenic series, Yangtze metaplatform, South China-Youjiang orogenic zone and Himalayan orogenic belt, are calculated and presented in this paper. In addition, the characteristics of petrochemical parameters, trace element contents and rare earth element distributions of different rock types of the granitoids in different geotectonic units are also sufficiently discussed.

The Okinawa Trough is located between the shelf-sea area of the East China Sea and the deep-sea area of western Pacific Ocean. More than 60 chemical elements in the sediments from the shelf area of the East China Sea, the Okinawa Trough and western Pacific Ocean were determined by advanced techniques including neutron activation analysis, X-ray fluorescence spectrometry, atomic fluorescence spectrometry and atomic absorption spectrometry. Quantitative comparisons of the element abundances of the sediments were made in terms of the enrichment coefficients (K) of the elements.K > 1.5 indicates enrichment (K = 1.5–2, weak enrichment; K = 2–4, strong enrichment) andK > 4, anomalous enrichment. The results show that the Okinawa Trough sediments are characterized by Hg anomaly and the enrichment of such elements as Au, Ag, Se, Te, Sb, Cd, Mn, Mo, etc. Detailed studies show that the excess Hg comes from hydrothermal solutions rather than from the continent, sea water, marine organisms, cosmic dust or volcanic rocks. Attributed to modern hydrothermal activities on the sea floor, Hg anomaly can be used as a geochemical indicator of modern seafloor hydrothermal activity.