胶东威海地区榴辉岩退变质的地球动力学信息

威海地区榴辉岩退变质过程表现为三个阶段：第一阶段,原生绿辉石分解形成的钠质单斜辉石＋斜长石合晶体,第二阶段,原生石榴石及钠质单斜辉石＋斜长石合晶体,周边出现角闪石＋斜长石栉状反应边;第三阶段,石榴石及钠质单斜辉石消失,其后榴辉岩相退变质的ｐ－ｔ演变轨迹呈压力相对温度快速降低的顺时针形式,反映本区榴辉岩折返的地球动力学过程可能是在经历了快速上升的构造侵位同时,晚元古宙巨量花岗岩浆可将榴辉岩块体携带到     

苏鲁地体榴辉岩形成过程中流体活动的氧同位素制约

对苏鲁地体西部东海地区榴辉岩及其共生片麻岩内部石英脉进行了氧同位素研究。石英脉及其寄主岩石榴辉岩和片麻岩中的石英与其他矿物之间达到了的氧同位素平衡，计算得到的平衡温度分别为：石英脉６６０－８４０℃，榴辉岩５９５－７２５℃，片麻岩５０５－６６５℃，石英脉的δ＾１８Ｏ值变化范围为－５．３－７．５‰，与寄主岩石的δ＾１８Ｏ相似，指示变质流体与寄主岩石保持氧同位素平衡，同时表明超高压变质作用期间或之后只存     

椎间盘退变动物模型的研究进展

椎间盘退变是各种脊柱退变性疾病发生的前提条件和病理基础,影响患病人群的身体健康和降低他们的生活质量,同时给家庭和社会带来负担.虽然国内外关于椎间盘退变研究较多,但其退变原因尚未十分清晰,使用相关动物模型对研究其退变机制及治疗手段具有重要意义.针对目前椎间盘退变动物模型的研究现状,本文就实验动物的选择及造模方法进行归纳总...     

微血管形成在腰椎间盘退变过程中的表现特征及影响因素

目的观察微血管形成在腰椎间盘退变过程中的病理表现特征,并分析其相关影响因素.方法选取48例行单节段腰椎后路经椎间孔减压椎间植骨融合内固定术患者,术中切取患处组织,冷冻切片后HE染色,观察病理改变,Weidner微血管计数法统计微血管密度.根据是否有微血管分为有微血管组、无微血管组,比较微血管形成的可能影响因素,对差异具有统计学意义的因素进一步行Logistics回归分析.结果 25例患者椎间盘内存在明显微血管形成,组织切片中存在典型的条形管腔结构,血管内皮细胞核有明显蓝染,微血管形成率为52.08%,MVD值平均为11.9±2.5.有微血管组椎间盘钙化率明显高于无微血管组,差异具有显著统计学意义(P0.01);有微血管组JOA评分明显低于无微血管组,腰椎疼痛VAS评分明显高于无微血管组,差异具有统计学意义(P0.05);椎间盘退变程度、椎间盘疝出程度两组间比较差异无统计学意义(P0.05).多因素回归分析显示:椎间盘钙化、腰椎疼痛VAS评分与退变椎间盘内微血管形成有明显相关性(OR值分别8.992,7.359,P值均0.05).结论椎间盘退变伴随着微血管形成,椎间盘钙化、腰椎疼痛VAS评分与退变腰椎间盘微血管形成有关.     

西秦岭铀矿床热液石英Pb同位素组成及其应用

作者分析了西秦岭地区各类岩石、花岗岩、含铀黄铁矿及早阶段热液石英Ｐｂ同位素组成，并将热液石英Ｐｂ同位素组成作为联系母源Ｐｂ与矿床Ｐｂ同位素组成的桥梁，与母源Ｐｂ及矿床Ｐｂ同位素组成进行了对比，花岗岩－石英－含铀黄铁矿Ｐｂ同位素组成具有线性演化关系，从而提出矿床中的铀来自隐伏构造－岩浆岩，而不是地层岩石。     

北淮阳富碱侵入岩带Pb同位素研究

北淮阳富碱侵入岩带中的中、基性岩Ｐｂ、Ｓｒ，Ｎｄ同位素分析结果及本区已发表的磁性和酸性岩的有关成果表明，它们是由最少地壳混染端元、年轻地壳端元和古老地壳端元混合而成．本研究指出了北淮阳Ｐｂ同位素省侵入岩Ｐｂ、Ｓｒ、Ｎｄ同位素特征的地球化学含义．     

Pb同位素在大水金矿深部找矿中的应用

大水金矿属于秦祁昆造山带,东昆仑-南秦岭褶皱系,西秦岭南亚带,大水金矿床共圈出96个矿体,组成3个较大的矿体群。通过研究Pb同位素在大水金矿深部矿体位置的隐伏系数、成矿截止深度与富集系数,说明了在西区深部及中区的南测找矿潜力巨大。     

巴马猪椎间盘退变模型的建立

目的 建立巴马猪腰椎间盘退变模型。方法 巴马小型猪6头,每组3头,分别为对照组(Con组),造模组(Mod组)。Con组不进行任何处理, Mod组在C形臂X光引导下确定猪L2-3、L3-4、L4-5、L5-6椎间隙,用1%的利多卡因进行浸润麻醉,用16G的引导针沿定位点穿刺椎间盘。穿透纤维环后侧后,呈放散状将椎间盘进行针刺破坏,每个间盘进行6次穿刺,每个角度间隔30度,分别于实验前及实验后1个月对巴马猪腰椎间盘行放射学及组织学观察。结果 Con组椎间盘未见明显变化, Mod组行MRI检查,发现进行穿刺的椎间盘出现间隙变窄,椎间盘后突,硬膜囊受压,髓核信号缺失,纤维环变形等改变,按照Pfirrmann分级标准,处理后的椎间盘在Ⅲ～Ⅳ级;病理组织学观察,与Con组比较,Mod组的椎间盘髓核呈白色胶冻状,穿刺部位椎间盘厚度下降,髓核发暗、含量减少,通道周围组织广泛硬化,纤维环结构粗糙。结论 C形臂X光定位下通过针刺破坏巴马小猪纤维环及椎间盘的方法,可以获得一种可靠的椎间盘退行病变模型。     

云南迪庆春都斑岩铜矿床S、Pb同位素组成—成矿物质来源的指示

春都铜矿是中甸岛弧带西斑岩带的一个典型矿床,对春都铜矿床矿石矿物开展了S、Pb同位素地球化学研究。矿区硫同位素组成非常稳定,黄铁矿、黄铜矿和方铅矿的~(34)δS值分别为-3.0‰~-0.14‰(平均~(-1).09‰),-6.54‰~-2.11‰(平均-3.44‰),-5.0‰~-3.6‰(平均-4.07‰)且依次降低,表明硫化物沉淀过程中硫同位素分馏基本达到平衡。16件硫化物样品的34δS均值为-2.41‰,表明硫主要为深部岩浆来源。矿石矿物铅同位素~(206)Pb/~(204)Pb,~(207)Pb/~(204)Pb,~(208)Pb/~(204)Pb比值分别为17.863~18.036,15.448~15.614和37.753~38.188,不同样品的铅同位素组成表明铅可能具有多源性,所有样品铅同位素投点均落入造山带区域或上地壳,表明铅具有壳幔混合来源的特征。这种硫铅同位素组成表明岩浆可能起源于俯冲洋壳板片的部分熔融并受到少量地壳物质的混染。     

桐柏山地壳结构的Pb同位素地球化学示踪研究

出露于桐柏山一带的桐柏杂岩,其放射成因Pb同位素组成介于低放射成因Pb同位素组成的大别核部杂岩和相对高放射成因Pb同位素组成的大别超高压变质杂岩之间,侵入于桐柏杂岩的鸡公山花岗岩明显不同于桐柏杂岩的Pb同位素组成,而与大别核部杂岩具有相似的Pb同位素组成.根据Pb同位素组成在地壳垂向剖面上的变化模型及花岗岩的岩浆源区分析,指出在区域地壳结构上,桐柏杂岩是位于大别核部杂岩之上但位于超高压变质杂岩之下的一个岩系.东部大别地区由于地壳剥露程度高,在大别核部杂岩之上的桐柏杂岩基本没有得到保存,而在桐柏地区,地壳剥露相对较浅,在桐柏杂岩之下的深部地壳中仍有类似于东部大别核部杂岩的分布.因此,在造山带的地壳结构上,桐柏地区和大别地区的地壳基底组成是统一的,现今它们在造山带中的分布仅仅反映造山带地壳不同暴露截面的差异.     

Discovery of Late Paleozoic retrograded eclogites from the middle part of the northern margin of North China Craton

The northern margin of the North China Craton (NCC), located between the Paleo-Asian Ocean tectonic region on the north and the NCC on the south, is a key region for studying the tectonic evolution of NCC. A Pre-cambrian retrograded eclogite (2500 Ma or 1800 Ma) was reported in Baimashi near Hengshan Mountain in the NCC, which is characterized by the vermicular symplec-tite of diopside and plagioclase with absence of ompha-cite[1,2]. In Hongqiyingzi Group from the middle part of the …     

Oxygen isotope compositions of eclogites in Rongcheng,Eastern China

Collected from the Rongcheng region,Shandong Province,the three types of eclogites suffering the UHP (i.e.ultra-high pressure )metamorphism have obviously different oxygen isotope compositions.The eclogites occurring in regional orthogneisses and ultramafic rocks have the oxygen isotope compositions of normal eclogites in the world,but the eclogites existing in marbles are extremely enriched in ^18 O.By applying oxygen isotope geothermometry ,for the all types of exlogites,the temperature estimates of quartz-garnet pair,in principle,indicate the formation temperatures of eclogites,so that the peak-metamorphic temperatures are estimated to be averagely little higher than 800℃ ,which are consistent with the estimates by using other geothermometers according to cation partitioning between coesisting phases ,The δ^18O values of eclogitic inclusions hosted in marbles from Yangguantun,Rongcheng region ,are far higher than the values of eclogites (including eclogitic inclusions in marbles ) from the Dabieshan and other places of the Sulu,The oxygen isotope compositions of various minerals indicate that the formation temperatures of eclogites from the Rongcheng region ,in genceral ,are higher than that from the Dabieshan and the southwestern part of the Sulu ,but the dispersive temperatures estimated by different mineral pairs probably refect that the UHP eclogites from the Rongcheng region generally suffered overprinted metamorphisms during the exhumation.     

Tectonic affinity of Paleozoic stratigraphic slices along the northern margin in Dabie Orogen, central China: evidence from Pb isotope of rocks

Metavolcanic and metasedimentary rocks from the Paleozoic tectono-stratigraphic units along the northern margin in the Dabie orogen show that there are two types of Pb isotopic compositions, which have some affined regularity with tectonic subdivision. Compared with the main tectonic units of the Qinling orogen, the Dingyuan Formation should be the part of the South Qinling orogenic belt or the northern margin of the Yangtze craton, characterized by less radiogenic Pb isotopic composition, and the Guishan Formation, Nanwan Formation-Foziling Group and the Carboniferous should be the part of the North Qinling orogenic belt which is extended to the east, characterized by more radiogenic Pb isotopic composition. These facts combined with the distribution of the geological units suggest that the Paleozoic subduction zone between the Yangtze and North China cratons should be located in the north boundary of the Nanwan Formation-Foziling Group or somewhere that is covered by the Nanwan Formation-Foziling Group now. From the Pb isotopic evidence and suggestion presented here, one aspect of the constraint is provided for determining the position of the Triassic collision suture between the two cratons.     

Revision of the genus Abrestheria (Crustacea: Conchostraca) from the Dabeigou Formation of northern Hebei, China

Re-examination of the type specimens of the conchostracan genus Abrestheria using a scanning electron microscope (SEM) has revealed details of carapace features of important taxonomic value, which have not been described hitherto. The new characteristics include: (1) small-sized reticulations on growth lines near the umbo; (2) serrated lower margins of growth lines; (3) punctae in the even lumina of reticulations; and (4) tubercles at the lower ends of the claviform radial lirae on the growth bands of the lower parts of the carapace. Consequently, the diagnosis of Abrestheria is revised, and a discussion is also made concerning relationships between Abrestheria and closely related genera, such as Eosestheriopsis, Eosestheria and Orthestheria, which have important biostratigraphic implications.     

Determination and geological significance of the eclogites from the northern Dabie Mountains, central China

Numerous eclogite-amphibolite blocks have been found along the Mayanling fault in the northern Dabie complex. Most of the eclogites are strongly retrograded and contain garnet, rutile and the amphibole-plagioclase symplectite. The occurrence of these eclogites may have something to do with the inverted movement of the Mayanling thrust fault.     

Revision of the genus Abrestheria (Crustacea: Conchostraca) from the Dabeigou Formation of northern Hebei, China

Re-examination of the type specimens of the conchostracan genus Abrestheria using a scanning electron microscope (SEM) has revealed details of carapace features of important taxonomic value, which have not been described hitherto. The new characteristics include: (1) small-sized reticulations on growth lines near the umbo; (2) serrated lower margins of growth lines; (3) punctae in the even lumina of reticulations; and (4) tubercles at the lower ends of the claviform radial lirae on the growth bands of the lower parts of the carapace. Consequently, the diagnosis of Abrestheria is revised, and a discussion is also made concerning relationships between Abrestheria and closely related genera, such as Eosestheriopsis, Eosestheria and Orthestheria, which have important biostratigraphic implications.     

Old EMI-type enriched mantle under the middle North China Craton as indicated by Sr and Nd isotopes of mantle xenoliths from Yangyuan, Hebei Province

Recent studies indicate that the Mesozoic litho- spheric thinning in North China was diachronous with that in west to the Taihangshan gravity lineament being later than in the eastern part of the North China Cra- ton[1―3]. During the Cenozoic, lithospher…     

Isotopic characteristics of the postorogenic granites in orogenic belt of northern China and their implications in crustal growth

The orogenic belt of northern China is characterized by widely developed postorogenic Ⅰ fractionated and A-type granites in the Phanerozoic. The isotopic data display relatively high ε Nd(t) and 206Pb/ 204Pb values and low I Sr ratio. The low T DM model ages (<100 Ma) suggest that the Neo-Proterozoic-Phanerozoic is one of the main stages in the continental growth.     

辽西冀北晚中生代的化石蜥蜴类(爬行纲:有鳞目)

个蜥矢部部龙趾大具有辽西冀北晚中生代已记录的蜥蜴类化石共4属5种,及2个未命名属种。这些化石自下而上可划分4蜴类化石带：中侏罗世杨氏矢部龙带(Yabeinosaurus youngi Zone)、早白垩世早期长趾大凌河蜥-细小龙组合带(Dalinghosaurus longidigitus-Yabeinosaurus tenuis Assemblage Zone)、早白垩世早期细小矢带(Yabeinosaurus tenuis Zone)及早白垩世晚期炭德氏蜥带(Teilhardosaurus canbonarius Zone)凌河蜥-细小矢部龙组合带中的蜥蜴类属种最为丰富且分布较广,为研究早期蜥蜴类的地理地史分重要价值。布长等