Abstract:

Gas chromatography of n-alkanes in the surface sediments appears as double peaks in the Chukchi and the Bering Sea. The high carbon peak is at MH nC_~25 —nC_~33 and the low carbon peak locates at MH nC_~16 —nC_~20 in the Chukchi Sea. The high carbon peak is at MH nC_~25 —nC_~27 and the low carbon peak locates at nC_~17 —nC_~22 in the Bering Sea. OEP are 0.9—3.81 and 0.409—3.26, the ratio of C-_~23 /C+_~24 are between 0.18—1.53 and 0.40—2.57; the ratio of TAB_~HC are 0.57—11.35 and 0.32—5.97 respectively. The results suggest that the substance input from terrigenous origin in the Chukchi Sea is larger than that in the Bering Sea. But the productivity in the surface water in the Bering Sea is higher than that in the Chukchi Sea. The composition characteristics of n-alkanes in the modern sediments of the Arctic is compared with that in the Antarctic as well as with that in the Bohai Sea, the Yellow Sea, The East China Sea and the South China Sea. The results indicate that the characteristics of terrigenous origin become weaker while marine biological inputs appear stronger from high to low latitudes. The discrepancy of composition characteristics of n-alkanes in different sea areas have been contributed by the process of sedimentation that influenced by environments and climates.