: The 3He/4He ratios of most eclogites from the Dabie-Sulu terrane range from 0.056 to 0.67 Ra; the data points fall into the mixing part of the crust and the mantle in the 3He-4He diagram. The 3He/4He ratios of eclog...: The 3He/4He ratios of most eclogites from the Dabie-Sulu terrane range from 0.056 to 0.67 Ra; the data points fall into the mixing part of the crust and the mantle in the 3He-4He diagram. The 3He/4He ratios of eclogites are obviously correlated with the types of their surrounding rocks. The helium isotope composition of the eclogites from the Bixiling complex possesses characters of mantle-derived rocks with the 3He/4He ratio being 5.6 Ra. The 4He concentration of the eclogites exhibits visible inverse correlation with the δ18O value of the quartz in the eclogites from the Sulu area. The δ18O values of the eclogites change synchronously with those of the country rocks. Those results suggest that protoliths of the eclogites were basic-ultrabasic rock bodies or veins intruding into the continental crust in the early stage; strong exchange and hybridization between the basic-ultrabasic rocks and continental rocks and the atmospheric water during the intrusion led to abrupt increase of the 3He/4He ratios, δ18O values and Nd(0) values of the intrusive bodies or veins, which show characters of continental rocks. This indicates that the eclogites are autochthonous.展开更多
Cenozoic basalts in the eastern part of Liaoning-Jilin contain abundant mantle-derived inclusions. The rock types of the ultramafic inclusions are composed mostly of spinel lherzolite and a few websterites. In order t...Cenozoic basalts in the eastern part of Liaoning-Jilin contain abundant mantle-derived inclusions. The rock types of the ultramafic inclusions are composed mostly of spinel lherzolite and a few websterites. In order to study the origin of inclusions, the concnetrations of several trace elements have been measured in samples by NAA. According to geochemical characteristics of trace elements, there are two types of spinel Iherzolite inclusions. The first type is refractory residues left after partial melting of the upper mantle and the second type is metasomatizing refractory residues. The websterites inclusions formed by segregation of basaltic melt derived from high degree of melting of mantle source rocks.展开更多
Two principal hydrothermal events have been recognized ,which resulted in the tin-bearing skarns at Red-A-ven ,Northwest Dartmoor.Tin was enriched during both the early (occurring as tin-bearing andradite) and late hy...Two principal hydrothermal events have been recognized ,which resulted in the tin-bearing skarns at Red-A-ven ,Northwest Dartmoor.Tin was enriched during both the early (occurring as tin-bearing andradite) and late hydrothermal events (mainly as malayaite stannite and cassiterite,accompanied by boron silicates and minor tungsten).Thermometric measurements of fluid inclusions in diopside,garnet,malayaite,tourmaline-quartz and axinite were carried out,suggesting that the early skarns were formed at the temperature above 600℃and the salinities ranging from 10 to 20 wt.% NaCl eq.while the late skarns at the temperatures of 350-460℃ and the salinities ranging from 30 to 50wt.% NaCl eq.The estimated minimum depths are 2856m(850 bar) for the early event and 2526m(185 bar) for the late event.The birefringence of the andradite might be related with the superimposition of late hydrothermal fluids.展开更多
Ⅰ. GEOLOGICAL SETTINGThe Bainaimiao Group outcrops in south-central part of Inner Mongolia (Fig. 1). It has been noted that the Ondor Sum ophiolite suite, mixture accumulation and Bainaimiao island arc volcano-sedime...Ⅰ. GEOLOGICAL SETTINGThe Bainaimiao Group outcrops in south-central part of Inner Mongolia (Fig. 1). It has been noted that the Ondor Sum ophiolite suite, mixture accumulation and Bainaimiao island arc volcano-sedimentary sequences as well-as Fe, Cu, Mo and Au ore deposits or prospects were developed in this area. There are some arguments on the mutual relation,展开更多
The heterocorals described by the authors were first found near Xilingaolei, 20kmnorthwest of Laevo-Alxa Banner in the Inner Mongolia Autonomous Region(Fig.1).Bore samples collected from Bacan No. 2 boring well belong...The heterocorals described by the authors were first found near Xilingaolei, 20kmnorthwest of Laevo-Alxa Banner in the Inner Mongolia Autonomous Region(Fig.1).Bore samples collected from Bacan No. 2 boring well belong to the ChouniugouFormation of the Lower Carboniferous. The thickness of this group is 173 m.展开更多
Ⅰ. INTRODUCTION The structure of an orthopyroxene was first determined by Warren and Modell when they found that orthopyroxene contains the typical SiO3 chains similar to those of diopside; Bystrm improved the atomic...Ⅰ. INTRODUCTION The structure of an orthopyroxene was first determined by Warren and Modell when they found that orthopyroxene contains the typical SiO3 chains similar to those of diopside; Bystrm improved the atomic parameters of enstatite; Ito studied the structure of bronzite with ionisat spectrometer; and Lindemann published the atomic coordinates for an orthoenstatite. Later the cell dimensions of natural ortho-展开更多
Among the numerous GGT projects in China, the GGT from Yadong to Golmud crossing the whole Tibetan Plateau stands out for its peculiar tectonic environment of continentcontinent collision orogeny and characteristic ge...Among the numerous GGT projects in China, the GGT from Yadong to Golmud crossing the whole Tibetan Plateau stands out for its peculiar tectonic environment of continentcontinent collision orogeny and characteristic geophysical fields of a co-existing thick yet warm crust. The terrestrial heat flow measurements have resulted in setting up a heat flow profile at the highest elevations on a global scale running through the 'Roof of the World'. It extends from south to north for about 1300 km, consisting of 22 heat flow values from 13 individual studied regions: Puma Lake (91 mW/m^2, average value, the same below),展开更多
文摘: The 3He/4He ratios of most eclogites from the Dabie-Sulu terrane range from 0.056 to 0.67 Ra; the data points fall into the mixing part of the crust and the mantle in the 3He-4He diagram. The 3He/4He ratios of eclogites are obviously correlated with the types of their surrounding rocks. The helium isotope composition of the eclogites from the Bixiling complex possesses characters of mantle-derived rocks with the 3He/4He ratio being 5.6 Ra. The 4He concentration of the eclogites exhibits visible inverse correlation with the δ18O value of the quartz in the eclogites from the Sulu area. The δ18O values of the eclogites change synchronously with those of the country rocks. Those results suggest that protoliths of the eclogites were basic-ultrabasic rock bodies or veins intruding into the continental crust in the early stage; strong exchange and hybridization between the basic-ultrabasic rocks and continental rocks and the atmospheric water during the intrusion led to abrupt increase of the 3He/4He ratios, δ18O values and Nd(0) values of the intrusive bodies or veins, which show characters of continental rocks. This indicates that the eclogites are autochthonous.
文摘Cenozoic basalts in the eastern part of Liaoning-Jilin contain abundant mantle-derived inclusions. The rock types of the ultramafic inclusions are composed mostly of spinel lherzolite and a few websterites. In order to study the origin of inclusions, the concnetrations of several trace elements have been measured in samples by NAA. According to geochemical characteristics of trace elements, there are two types of spinel Iherzolite inclusions. The first type is refractory residues left after partial melting of the upper mantle and the second type is metasomatizing refractory residues. The websterites inclusions formed by segregation of basaltic melt derived from high degree of melting of mantle source rocks.
文摘Two principal hydrothermal events have been recognized ,which resulted in the tin-bearing skarns at Red-A-ven ,Northwest Dartmoor.Tin was enriched during both the early (occurring as tin-bearing andradite) and late hydrothermal events (mainly as malayaite stannite and cassiterite,accompanied by boron silicates and minor tungsten).Thermometric measurements of fluid inclusions in diopside,garnet,malayaite,tourmaline-quartz and axinite were carried out,suggesting that the early skarns were formed at the temperature above 600℃and the salinities ranging from 10 to 20 wt.% NaCl eq.while the late skarns at the temperatures of 350-460℃ and the salinities ranging from 30 to 50wt.% NaCl eq.The estimated minimum depths are 2856m(850 bar) for the early event and 2526m(185 bar) for the late event.The birefringence of the andradite might be related with the superimposition of late hydrothermal fluids.
基金Sub-category of Key Project of Geosciences and Technology(75-55-03)of National "the Seventh Five-year Plan"
文摘Ⅰ. GEOLOGICAL SETTINGThe Bainaimiao Group outcrops in south-central part of Inner Mongolia (Fig. 1). It has been noted that the Ondor Sum ophiolite suite, mixture accumulation and Bainaimiao island arc volcano-sedimentary sequences as well-as Fe, Cu, Mo and Au ore deposits or prospects were developed in this area. There are some arguments on the mutual relation,
文摘The heterocorals described by the authors were first found near Xilingaolei, 20kmnorthwest of Laevo-Alxa Banner in the Inner Mongolia Autonomous Region(Fig.1).Bore samples collected from Bacan No. 2 boring well belong to the ChouniugouFormation of the Lower Carboniferous. The thickness of this group is 173 m.
文摘Ⅰ. INTRODUCTION The structure of an orthopyroxene was first determined by Warren and Modell when they found that orthopyroxene contains the typical SiO3 chains similar to those of diopside; Bystrm improved the atomic parameters of enstatite; Ito studied the structure of bronzite with ionisat spectrometer; and Lindemann published the atomic coordinates for an orthoenstatite. Later the cell dimensions of natural ortho-
基金Project supported by the National Natural Science Foundation of China
文摘Among the numerous GGT projects in China, the GGT from Yadong to Golmud crossing the whole Tibetan Plateau stands out for its peculiar tectonic environment of continentcontinent collision orogeny and characteristic geophysical fields of a co-existing thick yet warm crust. The terrestrial heat flow measurements have resulted in setting up a heat flow profile at the highest elevations on a global scale running through the 'Roof of the World'. It extends from south to north for about 1300 km, consisting of 22 heat flow values from 13 individual studied regions: Puma Lake (91 mW/m^2, average value, the same below),
