A Large Ductile Sinistral Strike-Slip Shear Zone and Its Movement Timing in the South Qilian Mountains, Western China

There is a large ductile shear zone, 2 km wide and more than 350 km long, inthe South Qilian Mountains, western China. It is composed of volcanic, granitic and calcareousmylonites. The microstructures of the ductile shear zone show nearly E-W extending subverticalfoliation, horizontal and oblique stretching lineations, shearing sense from sinistral to obliquesinistral strike-slip from east to west, 'A' type folds and abundant granitic veins. Measuredlattice preferred orientations (LPOs) of the mylonitic and recrystallized quartz of the graniticmylonite in the west segment suggest a strong LPO characterized by the dominant slip systems (1010) formed at high temperature (>650 deg C). K-feldspar of the mylonite shows an ^(39)Ar/^(40)Arhigh-temperature plateau age of 243.3 +- 1.3 Ma, and biotite, 250.5 +- 0.5 Ma, which represent theformation age of the ductile shear zone. The ^(39)Ar/^(40)Ar plateau ages of 169.7 +- 0.3 Ma and160.6 +- 0.1 Ma and the ^(39)Ar/^(40)Ar isochron ages of 166.99 +- 2.37 Ma and 160.6 +- 0.1 Ma ofbiotites in the mylonite represent the subsequent deformation age. These ages indicate that thisductile shear zone is similar to the Altun and South Kunlun sinistral ductile shear zones in itsages of movement, formation, reactivation and duration.

New Zircon U-Pb Geochronology of the Post-kinematic Granitic Plutons in the Diancang Shan Metamorphic Massif along the Ailao Shan-Red River Shear Zone and Its Geological Implications

The Ailao Shan-Red River fault zone is the boundary between the Yangtze block to the northeast and the Indochina block to the southwest.It is an important tectonic zone due to its role in the southeastward extrusion of the Indochina block during and subsequent to the Indian-Eurasian collision.Diancang Shan（DCS） high-grade metamorphic complex,located at the northwest extension along the Ailao Shan-Red River（ASRR） shear zone,is a representative metamorphic complex of the ASRR tectonic belt.Structural and microstructural analysis of sheared rocks in the high-grade metamorphic rocks reveals that they are coherent with solid-state high-temperature ductile deformation,which is attributed to left-lateral shearing along the ASRR shear zone.New LA-ICP-MS zircon U-Pb geochronological and microstructural studies of the post-kinematic granitic plutons provide a straightforward time constraint on the termination ductile left-lateral shearing and exhumation of the metamorphic massif in the ASRR shear zone.It is suggested that the left-lateral shearing along the ASRR shear zone ended at ca.21 Ma at relative lower-temperature or decreasing temperature conditions.During or after the emplacement of the young dikes at ca.21 Ma,rapid brittle deformation event occurred,which makes the DCS massif start fast uplift/exhumation and cooling to a shallow crustal level.

基于风环境优化的岭南高校教学组团形态布局设计研究

校园形态与环境舒适性的关系是校园建设的热门议题。探讨高校公共教学组团布局类型及关键设计要素与风环境评价指标的关系,目的在于为风环境导向下的公共教学组团空间形态控制提供思考路径。选取岭南地区54所建成高校公共教学组团作为研究对象,归纳总结组团布局类型,分析风环境相关设计要素(包括建筑朝向、建筑间距与围合形式),抽象高校公共教学组团理想模型,运用Phoenics软件进行夏季风环境模拟;设计单因子变量实验,分析不同因素与室外风环境的关联关系;对3个设计要素进行关联分析,探讨不同设计制约条件下的最优因素水平组合。结果显示,行列式布局在4种布局类型中室外风环境表现最优;当建筑根据地形呈斜向行列式布局时,组团室外风环境舒适性和空间感受较好;建筑间距与组团室外风环境呈正相关关系,但差异性较小;呈E型或S型围合的组团布局模式,连接体采用架空、挖洞等手法进行通透性处理,是兼顾室外风环境舒适性与空间需求的较优组团形式。

招远市玲南矿区金矿特征及找矿意义

招(远)—平(度)断裂带作为胶东三大主要金成矿带之一,历来备受学者关注。但是,关注焦点大都汇聚于招(远)—平(度)断裂带,而对其下盘的次级蚀变带却不够重视。基于此,依据玲南矿区地质成果报告,结合玲南矿区地质背景,分析研究断裂带下盘的1号、2号蚀变带赋存矿体及围岩蚀变等特征,总结金矿物的形态及赋存状态,明确了找矿标志和成因等因素,阐明了1号、2号蚀变带找矿意义和赋矿潜力,对深部找矿具有一定的指导意义。

岭南高温地区商业步行街夏季热环境测试——以南宁市民生路商业步行街为例

为掌握城市商业步行街热环境状况,对广西南宁市民生路商铺、街道环境和人行通道进行夏季热环境测试,采用定点定时连续测试方法。在白天10个小时中,选取商业步行街不同建筑朝向较具代表性的10个测点,测点多在骑楼下人行道。进行空气温度和相对湿度、黑球温度、地面温度的测试。通过对整个商业步行街道路遮阳和下垫面材质实地观察和测试数据分析,结合国内外城市建设成功经验,对今后商业步行街建设就街道热环境及购物环境舒适性等提出可行性建议。建议商业步行街除了机动车禁行及提供行人休息的椅子,还应考虑商业步行街行道树或景观树的选择、道路遮阳方式,以提供舒适的环境。

岭南园林的学术定义

岭南是我国南岭的五座山脉(越城岭、都庞岭、萌渚岭、骑田岭和大庾岭)以南地区的统称,地域范围从秦汉至唐朝大致包括广东、广西、海南岛和越南北部红河三角洲大部。北宋以后岭南地域不再包括越南,沿袭至今,含广东、广西、香港、澳门、海南省(区)全境,与华南政区的地理版图一致。"岭南园林"一词最早出现在1962年广东园林学会成立大会上林西同志的开幕讲话中,后被业界广泛采用。岭南园林是中国岭南地区风景园林的概称,具有鲜明的地方特色。广义上讲,它泛指发生在岭南地区的风景园林营造活动及相关作品;狭义而论,它代称在岭南地区营造的具有岭南文化与自然特色的风景园林实体。其英文译名,宜为"Southern China Landscape Architecture"(SCLA)。岭南园林可作为地带园林学研究的特定类型,是中国热带园林营造的传统形式之一。明确岭南园林的学术定义,对于促进岭南园林事业的健康发展和国际传播具有积极意义。

大兴安岭地区岭南农业开发区建设有机食品基地的研究

文章通过对大兴安岭岭南农业开发区的自然地理条件、生态环境、社会环境等因素的分析,阐述了岭南农业开发区建设有机食品基地的优势条件、建设原则及对当地经济的推动作用,并就如何建设提出相应的措施。

Thermoelasticity and stability of natural epidote at high pressure and high temperature:Implications for water transport during cold slab subduction

Epidote is a typical hydrous mineral in subduction zones.Here,we report a synchrotron-based single-crystal X-ray diffraction(XRD)study of natural epidote[Ca1.97Al2.15Fe0.84(SiO4)(Si2O7)O(OH)]under simultaneously high pressure-temperature(high P-T)conditions to~17.7 GPa and 700 K.No phase transition occurs over this P-T range.Using the third-order Birch-Murnaghan equation of state(EoS),we fitted the pressure-volume-temperature(P-V-T)data and obtained the zero-pressure bulk modulus K_(0)=138(2)GPa,its pressure derivative K'_(0)=3.0(3),the temperature derivative of the bulk modulus((∂K/∂T)P=-0.004(1)GPa/K),and the thermal expansion coefficient at 300 K(α_(0)=3.8(5)×10^(-5)K^(-1)),as the zero-pressure unit-cell volume V_(0)was fixed at 465.2(2)Å^(3)(obtained by a single-crystal XRD experiment at ambient conditions).This study reveals that the bulk moduli of epidote show nonlinear compositional dependence.By discussing the stabilization of epidote and comparing its density with those of other hydrous minerals,we find that epidote,as a significant water transporter in subduction zones,may maintain a metastable state to~14 GPa along the coldest subducting slab geotherm and promote slab subduction into the upper mantle while favoring slab stagnation above the 410 km discontinuity.Furthermore,the water released from epidote near 410 km may potentially affect the properties of the 410 km seismic discontinuity.

Exposed Cross-section of the Archaean Lower Crustin the Shanxi-Hebei-Inner Mongolia Border Region:Problems and Prospects

The Archaean lower crust represented by granulite facies rocks, which is rare in China, is found to be exposed in the Shanxi-Hebei-Inner Mongolia border region. Studies of the regional structure and deformation and metamorphism of the region indicate that there occurred at least two phases of deformation and metamorphism in the region. Early-phase nearly E-W-directed deformational structure is well preserved in the Zhangjiakou-Xuanhua area. Observations of the features of the geological structure from north to south (in the Hengshan metamorphic terrain) have revealed a possible exposed cross-section through the Archaean lower crust. The structure was superimposed by a NE-SW-trending high-temperature ductile shear zone in the Datong area in the late phase, thus reworking the Archaean sequence.