| An amount of mantle-derived xenoliths and megacryst, which are excellent samples for research of the mantle, were widely found in Yishu areas of Shandong Province. And more and more attentions of Chinese geologists were drew to the fluids degassed from these rocks because of its importance on the research of mantle structure, compositions and evolving, etc, and the noble gas research of these fluids is a new and useful method for these researches.We analyzed the fluid compositions of mineral separates of xenoliths by spectrograph of MAT271. The primary compositions are CC2 CO and HI in the mineral separates of mantle-derived xenoliths in YiShu areas, and CH4, N2, C2H4, C2H6, etc, take its second place. There are usually more fluids in pyroxene than in olivine for the same xenolith sample, and the fo2 is always different for olivine and pyroxene in the same xenoliths that were sampled from the fault zone, but aren't at outer of faults. There are only one top for fluid degassing of olivine and pyroxene. The degassing characters of primary compositions are: 500C being always top for CH4; degassing of H2 increasing with increasing temperature, but just the reverse for CO2, Three parts which maybe correlate to the evolving stages of mantle fluids, were distinguished according to the fluid compositions at different temperatures.The noble gas isotopes of whole rocks, mineral separates, megacrysts and basalts were also analyzed by spectrograph of MM5400. The results suggest that there are abundance differences in noble gas isotopes among different rocks and separates, and also among different areas. As a whole, the abundance of 4He, 20Ne, 40Ar 84Kr,132Xe are always highest in the basalts, and often lower in separates, but usually mediate in whole rocks. And 40Ar and 84Kr are most striking in the abundance difference for different areas.As for the ratios of isotopes, 3He/4He are often between 0.115 and 2.7Ra in whole rocks and mineral separates, and always lower in whole rocks than in its mineral separates; 3.4-11.3Ra of 3He/4He were got in megacryst, and 10-8 of 3He/4He, which are as same as mediate ratio of crust, were got in basalts. Ratios of 40Ar/36Ar are usually lower in all rocks and separates, and between 296.5-864, but often inadequate to 400. There are little difference for ratios of Ar/ Ar in different rocks and mineral separates, and the higher ratios were also got in basalts. All ratios of 20Ne/22Ne are higher in the rocks and mineral separates than in the atmosphere, and between 10.19 and 13.10, which are higher than other areas of eastern China, and as same as MORB and OIB. The isotopic ratios of Kr, Xe in rocks and separates are not distinguished from the atmosphere, and no difference in different rocks.The noble gas isotopes suggest that there are some radiogenic 4He and 40Ar in whole rocks; and both radiogenic and fractionated parts were found in basalts. And the fluids of mineral separates, which represent the typical parts of the mantle-derived fluids, show a mixed character of atmosphere-mantle at the isotopic map of He-Ne, He-Ar and Ne-Ar.The studies on the alliance of noble gas and CO2, CH4, N2 are very valid for discussionon the source. Based on the ratios of 3He/4He, CO2/3He, CH4/3He and N2/Ar, we can distinguish three sources of mantle, atmosphere and crust. And these ratios of the mineral separates of Yishu area are successively: CO2/3He=28-1050x109, CH4/3He=11-1642x107, N2/Ar=927-56596, N2/3He=2.47-26.73 x 109, and imply a mixed source at differently allied map.The ratios and abundance of noble gas isotopes of the mantle fluids are constrained by its tectonic-settings. And the characters of the noble gas, especially the elements of He and Ar, are distinct in different tectonic-settings. According to the isotopic ratios of He, Ne and Ar, the tectonic-settings of Middle Ocean Ridge(MORB), Ocean Island(OIB), Subduction Zone, Continental Mantle, Continental Hotspot and Margin of Continental Plate, which separately stand for different sources, may be recognized. And three regions...
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