广西栗木钨锡铌钽矿区流体包裹体及氢氧同位素研究   总被引：2，自引：0，他引：2  

刘翔 《地质与勘探》2016,52(6):1016-1028

本文通过对广西栗木矿区金竹源矿床和水溪庙矿床的流体包裹体研究,得出该矿区流体包裹体主要有两相H_2O-NaCl和H_2O-NaCl-CO_2两种类型。显微测温结果表明:两相H_2O-NaCl型流体包裹体均一温度主要集中于181.9~258.8℃,盐度w(Na Cleq)主要集中于4.01%~6.87%,密度0.690~0.988 g/cm3;H_2O-NaCl-CO_2型流体包裹体均一温度为178.5~331.1℃,主要集中在两个温度段,分别为高-中温段(265.3~315.5℃)和中-低温段(202.3~264.1℃),盐度w(NaCleq)主要集中在0.21%~5.05%,密度为0.678~0.886 g/cm3。栗木矿区成矿流体有两个温度集中段,且具有低盐度、低密度的特征。氢氧同位素研究结果表明:金竹源矿床钨锡铌钽矿化花岗岩石英δD值为-73.6‰~-62.8‰,δ~(18)OV-SMOW值为7.5‰~8.9‰,计算得δ~(18)OH2O值为6.00‰~7.40‰;水溪庙矿床钨锡铌钽矿化花岗岩石英δD值为-73.8‰~-58.3‰,δ~(18)OV-SMOW值为11.0‰~13.2‰,计算得δ~(18)OH2O值为9.50‰~11.70‰,水溪庙矿床含钨锡石英脉石英δD值为-75.3‰~-56.6‰,δ~(18)OV-SMOW值为11.8‰~14.1‰,计算得δ~(18)OH2O值为2.20‰~4.50‰。栗木矿区钨锡铌钽矿化花岗岩成矿流体来源于岩浆水,含钨锡石英脉成矿流体来源于岩浆水和大气降水的混合流体。  相似文献   

Anisotropies in Mechanical Behaviour,Thermal Expansion and P-Wave Velocity of Sandstone with Bedding Planes     

Hui Zhou  Haitao Liu  Dawei Hu  Fanjie Yang  Jingjing Lu  Fan Zhang 《Rock Mechanics and Rock Engineering》2016,49(11):4497-4504

  相似文献   

Effect of High Temperature on Mineralogy,Microstructure, Shear Stiffness and Tensile Strength of Two Australian Mudstones     

Xianfeng Liu  Chonglei Zhang  Shengyang Yuan  Stephen Fityus  Scott William Sloan  Olivier Buzzi 《Rock Mechanics and Rock Engineering》2016,49(9):3513-3524

  相似文献   

ISRM Suggested Method for In Situ Microseismic Monitoring of the Fracturing Process in Rock Masses     

Ya-Xun Xiao  Xia-Ting Feng  John A. Hudson  Bing-Rui Chen  Guang-Liang Feng  Jian-Po Liu 《Rock Mechanics and Rock Engineering》2016,49(1):343-369

  相似文献   

Sequential Indentation Tests to Investigate the Influence of Confining Stress on Rock Breakage by Tunnel Boring Machine Cutter in a Biaxial State     

Jie Liu  Ping Cao  Dongya Han 《Rock Mechanics and Rock Engineering》2016,49(4):1479-1495

  相似文献   

Effects of low- to high-angle normal faults on sedimentary architectures in the Eocene Wenchang Formation,Enping Sag,Pearl River Mouth Basin,South China Sea     

Q. H. Liu  Y. Shu  X. M. Zhu  X. H. Yang  M. Tan 《Australian Journal of Earth Sciences》2016,63(7):903-922

The effects of low- to high-angle (>30°) normal faults on sedimentary architectural units in the Eocene Wenchang Formation, Enping Sag, Pearl River Mouth Basin (PRMB), South China Sea were investigated utilising a high-quality 3D seismic data set and restored paleogeomorphology. It has been shown that sequence stratigraphic units and sedimentary architecture are significantly controlled by the low- to high-angle normal faults. The Wenchang Formation, a second-order sequence, can be subdivided into two para-second-sequences (the Lower and Upper Wenchang sequences, E₂W^L and E₂W^U) and seven third-order sequences (from base to top: SQ1～SQ7). The low-angle fault confined sequence architecture of the Wenchang Formation is mainly characterised by lateral stacking with the ratio of the vertical subsidence (V) to horizontal slip (H) being reduced from 1/2 for E₂W^L to 1/6 for E₂W^U. In contrast, the high-angle fault confined sequence is characterised by vertical stacking with the ratio of V/H close to 1 for sequences SQ1 to SQ7. In the 3D seismic area, the features of sediment-dispersal pattern were interpreted based on an integrated analysis of paleogeomorphology, seismic reflection characteristics, stratal thickness distribution and multiple attribute clustering. The results show that the large-scale fan delta, belt-shape lacustrine deposit and bird-foot braided delta systems mainly developed in the low-angle fault confined sequences, whereas small-scale fan delta, rhombus-shaped lacustrine deposit and lobe-shaped braided delta systems inherited tectono-sedimentary architectures in the high-angle fault confined sequences.  相似文献   

Sedimentary facies analysis and depositional model of gravity-flow deposits of the Yanchang Formation,southwestern Ordos Basin,NW China     

F. Liu  Y. Li  M. Xue  J. Sun 《Australian Journal of Earth Sciences》2016,63(7):885-902

During the deposition of the Chang-7 (Ch-7) and Chang-6 (Ch-6) units in the Upper Triassic, gravity flows were developed widely in a deep lake in the southwestern Ordos Basin, China. Based on cores, outcrops, well-logs and well-testing data, this paper documents the sedimentary characteristics of the gravity-flow deposits and constructs a depositional model. Gravity-flow deposits in the study area comprise seven lithofacies types, which are categorised into four groups: slides and slumps, debris-flow-dominated lithofacies, turbidity-current-dominated lithofacies, and deep-water mudstone-dominated lithofacies. The seven lithofacies form two sedimentary entities: sub-lacustrine fan and the slump olistolith, made up of three and two lithofacies associations, respectively. Lithofacies association 1 is a channel–levee complex with fining-/thinning-upward sequences whose main part is characterised by sandy debris flow-dominated, thick-bedded massive sandstones. Lithofacies association 2 represents distributary channelised lobes of sub-lacustrine fans, which can be further subdivided into distributary channel, channel lateral margin and inter-channel. Lithofacies association 3 is marked by non-channelised lobes of sub-lacustrine fans, including sheet-like turbidites and deep-lake mudstones. Lithofacies association 4 is represented by proximal lobes of slump olistolith, consisting of slides and slumps. Lithofacies association 5 is marked by distal lobes of slump olistolith, comprising tongue-shaped debris flow lobes and turbidite lobes. It is characterised by sandy debris flow, muddy debris flow-dominated sandstone and sandstone with classic Bouma sequences. Several factors caused the generation of gravity flows in the Ordos Basin, including sediment supply, terrain slope and external triggers, such as volcanisms, earthquakes and seasonal floods. The sediment supply of sub-lacustrine fan was most likely from seasonal floods with a high net-to-gross and incised channels. Triggered by volcanisms and earthquakes, the slump olistolith is deposited by the slumping and secondary transport of unconsolidated sediments in the delta front or prodelta with a low net-to-gross and no incised channels.  相似文献   

Role of horizontal density advection in seasonal deepening of the mixed layer in the subtropical Southeast Pacific     

Qinyu Liu  Yiqun Lu 《大气科学进展》2016,33(4):442-451

The mechanisms behind the seasonal deepening of the mixed layer(ML) in the subtropical Southeast Pacific were investigated using the monthly Argo data from 2004 to 2012. The region with a deep ML(more than 175 m) was found in the region of(22?–30?S, 105?–90?W), reaching its maximum depth(～200 m) near(27?–28?S, 100?W) in September. The relative importance of horizontal density advection in determining the maximum ML location is discussed qualitatively. Downward Ekman pumping is key to determining the eastern boundary of the deep ML region. In addition, zonal density advection by the subtropical countercurrent(STCC) in the subtropical Southwest Pacific determines its western boundary, by carrying lighter water to strengthen the stratification and form a "shallow tongue" of ML depth to block the westward extension of the deep ML in the STCC region. The temperature advection by the STCC is the main source for large heat loss from the subtropical Southwest Pacific. Finally, the combined effect of net surface heat flux and meridional density advection by the subtropical gyre determines the northern and southern boundaries of the deep ML region: the ocean heat loss at the surface gradually increases from 22?S to 35?S, while the meridional density advection by the subtropical gyre strengthens the stratification south of the maximum ML depth and weakens the stratification to the north. The freshwater flux contribution to deepening the ML during austral winter is limited. The results are useful for understanding the role of ocean dynamics in the ML formation in the subtropical Southeast Pacific.  相似文献   

Reference evapotranspiration change and its sensitivity to climate variables in southwest China   总被引：2，自引：0，他引：2  

Tiegang Liu  Longguo Li  Jianbin Lai  Chao Liu  Wenhua Zhuang 《Theoretical and Applied Climatology》2016,125(3-4):499-508

  相似文献   

Spatiotemporal characteristics of precipitation changes in the Pearl River Basin,China     

Bingjun Liu  Junfan Chen  Wenxiu Lu  Xiaohong Chen  Yanqing Lian 《Theoretical and Applied Climatology》2016,123(3-4):537-550

  相似文献