Carbon isotope anomaly in marbles associated with eclogites from the Dabie Mountains

This is a report of carbon isotope anomaly in marbles associated with the UHP eclogites from the Dabie Mountains. The results place constraints on the degree of crust-mantle interaction during the UHP metamorphism.     

Isotope composition of helium in eclogite from the Dabie Mountains, central China and its geological significance

Isotopic geochemical characteristics of helium in garnet and omphacite of eclogite in the Dabie Mountains are discussed. Concentrations of 3He and 4He in garnet and omphacite are 3.9×10 -14- 24.0×10 -14 and 0.48×10 -7-9.42×10 -7cm+3·g -1, respectively. Values of 3He/ 4He have a range of (1.19-4.63)×10 -7. Helium in the eclogite is derived from both mantle and crust. Isotopic geochemical data of helium indicate that eclogite in the Dabie Mountains might be formed in depleted mantle and the age of the cologite would be Indo-China epoch.     

皖西大别山区野生攀援观赏植物资源与应用研究

通过对皖西大别山区野生攀援观赏植物资源的调查研究,本区有野生攀援植物157种具有较高观赏价值。根据其攀援特性分为缠绕类75种、吸附类17种、卷须类27种、蔓生类38种。探讨了其在园林绿化中的应用形式,对本区野生攀援观赏植物进行了总体评价,并对其开发利用提出了建议。     

Pb isotopic geochemical study on the crustal structure of Tongbaishan

Pb isotopic composition of the Tongbai complex, distributed in the Tongbaishan to the west of the Dabieshan, ranges between the Dabie core complex and the Dabie ultral-high pressure (UHP) metamorphic complex, the latter having more radiogenic Pb isotopic composition than the former. Granites from the Jigongshan pluton, which intruded mainly into the Tongbai complex, are distinct from the Tongbai complex but similar to the Dabie core complex in Pb isotopic composition, showing that the magma of the Jigongshan granites was derived from the partial melting of the Dabie core complex. According to Pb isotopic compositional variation model in the vertical crustal section and magma source from the Jigongshan pluton, it is suggested that the Tongbai complex was an upper rock serial of the Dabie core complex, which is beneath the Dabie UHP metamorphic complex in the crustal structure of the Tongbai-Dabie orogenic belt. The Tongbai complex was not well preserved in the Dabie area due to the high exhumed crustal section. However, the crustal section in the Tongbai area was exhumed less than that in the Dabie area, and the deep crust in the Tongbai area still contains the basement composition similar to the Dabie core complex. Therefore, the crustal basements from the Dabie to Tongbai areas are united. The present distribution of the basement blocks in different locations of the Tongbai-Dabie orogenic belt reflects different exposure of the crustal section.     

Triassic U-Pb age for zircon from granites in the Tonghua area and its response to the Dabie-Sulu ultrahigh-pressure collisional orogenesis

Single-grain zircon U-Pb dating was carried out to constrain the emplacement timing of granitic plutons at Chaxinzi, Xiaoweishahe and Longtou in the Tonghua area, south of Jilin Province. The results show that these plutons formed in the Triassic with ages of 203—217 Ma. Geological and geochemical characteristics indicate that the plutons are composed of quartz diorite and granite. The former was derived from partial melting of mafic lower crust, whereas the latter originated from thickened crust with garnet as the residue in the source. It appears that protoliths of these two types of granitits are different although they have the same emplacement age. Considering that these plutons are petrologically different from the coeval granites in the Xingmeng (Xing‘an-Mongolian) to Jihei (Jilin-Heilongjiang) orogenic belt in the north, it is suggested that their formation was related to the Dabie-Sulu ultrahigh-pressure collisional orogenesis since their ages are only 10—20 Ma younger than timing of the ultrahigh-pressure metamorphism, but comparable to that of the first rapid exhumation of the ultra-high-pressure metamorphic rocks and the emplacement of the post-collisional granites.     

Age of granulite from Huangtuling, Dabie Mountain: Pb-Pb dating of garnet by a stepwise dissolution technique

A new stepwise dissolution scheme, involving acids with different properties, enables the selective recovery of radiogenic and common Pb from a mineral, and makes single-mineral Pb-Pb dating possible. Garnet from a granulite sample from Huangtuling, northern Dabie Mountain yields a Pb-Pb isochron age of (1998 ±35) Ma, which is interpreted as the timing of peak metamorphism of granulite facies.     

Three-dimensional crustal velocity structure of P-wave in East China from wide-angle reflection and refraction surveys

The 3-D crustal structure of P-wave velocity in East China is studied based on the data obtained by wide-angle seismic reflection and refraction surveys.The results suggest that a deep Moho disconti-nuity exists in the western zone of the study region,being 35―48 thick.High-velocity structure zones exist in the upper crust shallower than 20 km beneath the Sulu and Dabie regions.The cause of high-velocity zones is attributable to high-pressure metamorphic(HPM) and ultra-high-pressure metamorphic(UHPM) terran...     

大别山区产葛根黄酮对CCl4诱导的小鼠化学性肝损伤保护作用

研究大别山区葛根总黄酮（TPF）对CCl4诱导小鼠化学性肝损伤的保护作用及可能的作用机制。采用1次性腹腔注射（ip）0．1％CCl4花生油溶液（10ml／kg）建立小鼠化学性肝损伤模型。TPF连续灌胃（ig）14d后摘眼球取血,分离血清,测定血清中丙氨酸氨基转移酶（ALT）和天门冬氨酸氨基转移酶（AST）活性;剖腹取肝,制备10％肝匀浆,测定肝组织中超氧化物歧化酶（SOD）、丙二醛（MDA）、干扰素-γ（IFN-γ）、肿瘤坏死因子-α（TNF-α）活性;进行肝组织病理切片,观察肝组织病理学变化。结果显示TPF能降低CCl4诱导的化学性肝损伤小鼠血清中ALT、AST和肝匀浆中MDA、IFI-γ、TNF-α的活性及增强肝匀浆中SOD的活力。其作用机制可能与抗氧化和降低肝组织中IFN-γ、TNF-α水平有关。     

大别山北麓高煤级煤显微裂隙分布特征

通过煤岩学方法研究大别山北麓杨山煤系高煤级煤中的显微裂隙,探讨了不同变形-变质类型煤的裂隙分布特征及其影响因素.大别山地区特殊的地质背景,形成了各种级别的构造裂隙,尤其是受到多期构造作用和岩浆活动的影响,使得高煤级煤中显微裂隙的分布及演化具有特殊性和复杂性.     

Discovery of the eclogite and its petrography in the Northern Dabie Mountain

Eclogite from the Northern Dabie Mountain is a new finding by the authors. These eclogites in foliated perdotite are enveloped by banded gneiss and occur in the mafic-ultramafic rock belt. They are mainly composed of omphacite, garnet, diopside, orthopyroxene, amphibole, plagioclase and magnetite, and a small amount of rutile, spinel, olivin and 鏾rundum. The mineral association of peak metamorphism of the eclogite is omphacite+garnet+rutile. The existence of eclogite in the Northern Dabie Mountain implies that there was an eclogitic metamorphism prior to the granulitic facies one in the mafic-ultramafic rock belt.