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811.
812.
813.
The early permian reef belt is distributed in the southern side of eastern Kunlun, north area of Qinghai-Tibet Plateau. The
core-reef facies of thc reel extends from Tuosuo Lake to Huashixia. Lots of reef breccia was found at the southern slope of
the mre-reef belt, and to the north of the reef belt there is back-reef limestone. Cacisponges, hydrozoa, bryozoa,Tabulozoa, Tubiphytes and red algae are the main frame-building organisms.Archaeolithoporella, laminated blue-green algaes,Tabulozoa andTubiphytes played a role of binding or encrustating. There are many kinds of epibiont in the mf, including brachiopod, gasterid, foraminifera,
echinoderm and simple coral. The type and the characteristics of the reef-building organisms in eastern Kunlun and Animaqing
are basically thr same as those in the south of Chi 相似文献
814.
The evolution of methane carbon isotope with depth has been discussed based on diagenetic reaction kinetics and isotopic Rayleigh
fractionational theory. A mathematical model to describe data of methane carbon isotope for the Liaohe oil field has been
established. 相似文献
815.
816.
817.
An oxygen isotope temperature record from 381 to 166 kaB. P. (230Th/234U dating and tuned ages) has been obtained by combining data on the isotopic composition of calcites with that of fluid inclusions
trapped in a stalagmite from a limestone cave in which a fossil cranium deposited. Several laminae in microsequence of the
stalagmite represent climatic events or shifts. The Nanjing man fossil was older than 381 kaB. P. 相似文献
818.
The Juancheng chondrite, a new meteorite falling recently in Juancheng County, Shandong Province, China, is classified as an H5 (S2) chondrite based on the compositions of olivine (Fa= 19.2, σ Fa=0.46) and low-Ca pyroxene (Fs=16.9, σ Fa=0.4). The plagioclase in the Juancheng chondrite is rich in CaO, indicating a relatively high metamorphic temperature the parent body underwent. 相似文献
819.
Discovery of eclogite at northern margin of Qaidam Basin, NW China 总被引:19,自引:0,他引:19
Jingsui Yang Zhiqin Xu Haibing Li Cailai Wu Junwen Cui Jianxin Zhang Wen Chen 《科学通报(英文版)》1998,43(20):1755-1755
Eclogite was first discovered at the northern margin of the Qaidam Basin in this study. It occurs as pods in the gneiss sequence of Middle to Upper Proterozoic age and is mainly composed of garnet, omphacite, phengite and rutile. The garnets contain 44%-62% of almandine, 15%-33% of grossular and 12%-30% of pyrope molecules, and the omphacites contain 40%-46% of jadeite. Applying garnet_clinopyroxene thermometry and jadeite geobarometry, the peak conditions of eclogite facies metamorphism occurred at about (722±123)℃ and at the pressure of up to c. 22 ×10 8 Pa. 相似文献
820.
The relaxation of the highly vibrationally excited CO (v = 1–8) by CO2 is studied by timeresolved Fourier transform infrared emission spectroscopy (TR FTIR). 193 nm laser photolysis of the mixture
of CHBr3 with O2 generates the highly vibrationally excited CO(v) molecules. TR FTIR records the intense infrared emission of CO(v→v-1). The
vibrational populations of each level of CO(v) have been determined by the method of spectral simulation. Based on the evolution
of the time resolved populations and the differential method, 8 energy transfer rate constants of CO(v = 1–8) to CO2 molecules areobtained: (5.7±0.1), (5.9±0.1), (5.2±0.2), (3.4±0.2), (2.4±0.3), (2.2±0.4), (2.0±0.4) and (1.8±0.6) (1014 cm3 · molecule−1 · s−1), respectively. A two-channel energy transfer model can explain the feature of the quenching of CO(v) by CO2. For the lower vibrational states of CO, the vibrational energy transfers preferentially to the u3 mode of CO2 For the higher levels, the major quenching channel changes to the vibrational energy exchange between CO(v→v-1) and the u1 mode of CO2. 相似文献