内蒙古赤峰地区馒头沟铜矿地质特征及成因研究

馒头沟铜矿是近年来在内蒙古赤峰地区发现的一处砂(页)岩型铜矿,在内蒙乃至北方属首次发现。该文在区域地质背景、矿区地质及矿化特征方面对该矿进行了初步的分析研究,并讨论了其矿床类型、成矿物质来源及成因,可进一步指导馒头沟矿床的勘查和认识,且对内蒙古乃至北方晚二叠世寻找同类矿床具有一定的地质意义。     

基于多时相Landsat TM/ETM的阿尼玛卿山冰川变化监测

采用遥感及地理信息系统技术,利用多时相Landsat TM/ETM影像和数字高程模型(SRTMDEM),结合中国冰川目录,获得阿尼玛卿山地区不同年份的冰川范围,进行冰川变化监测。综合分析该冰川的变化情况,计算冰川进退变化速率,并对其中4个变化较大的冰川进行详细的分析统计。结果表明:从1991年至2009年,阿尼玛卿山地区既有退缩冰川也有前进冰川,其中冰川退缩面积为15.30km2,前进面积为4.46km2。总体面积持续退缩,其中退缩最大的冰川长度缩短了900m,其它冰川也存在不同程度的变化。     

Dynamical Control of Pacific Oceanic Low-frequency Variability on Western Boundary and Marginal Seas

The adjustment of sea surface height (SSH) around the coasts of the Japan/East Sea (JES) and the South China Sea (SCS) basins subjected to extratropical Pacific Oceanic low frequency variability is studied using a Kelvin-planetary wave model and a high resolution numerical model. It is found that the modulation of SSH around the coast of Japan is mainly determined by slow adjustment of planetary waves, which radiate from the west coast of Honshu and Hokkaido due to the coastal Kelvin wave. In contrast, the SSH modulation around the cost of the South China Sea basin is mainly determined by the coastal Kelvin wave, which transfers the anomalous SSH into the SCS via the Luzon Strait and out via the Mindoro Strait. The planetary waves radiating from the west coast of Palawan establish a nearly uniform SSH anomaly in the southern part of the SCS, bounded by an eastward jet at the latitude of the Mindoro Strait. Along the western boundary, SSH anomaly decreases almost linearly toward the south, in accordance with the changing local deformation radius. In these two marginal seas, the mean subtropical Pacific gyre circulation enhances SSH modulation induced by extratropical Pacific low frequency variability. Overall, the SSH adjustment in the JES and the SCS predicted by the analytical model agrees well with the numerical model simulation. Application of this model to interaction between these marginal seas and the open ocean is discussed.     

基于小波变换方法的包头台形变分析

采用小波变换方法相继对包头台洞体应变和水管倾斜进行处理,研究形变数据固体潮、同震响应和周期性特征等。采用db4作为母小波对包头台形变进行5阶小波分解．分解后的细节部分能清晰地显示出包括1／3日波、半日波、日波和半月波等在内的固体潮汐波。对于2008年以来全球发生的M≥8．0级地震．包头台水管倾斜NS分量均有显著的同震响应现象发生．且在小波分解后的不同阶曲线中同震响应后续波形表现各异．另外在部分地震之前能观测到异常变化。采用Moflet小波作为母小波对包头台水管倾斜NS分量进行小波变换分析．获得的小波变换系数分布图能清晰地显示出倾斜数据中存在的包括半日潮和日潮在内的周期特征及其随时间变化情况。     

中美两国全球6级以上地震目录对比分析

中国地震台网中心(CENC)和美国国家地震信息中心(NEIC)提供的全球地震目录经常出现较大偏差.CENC发震时刻较早,CENC震源深度较深.2001年至2010年全球6.0级以上地震约11.67％存在明显目录偏差,印度洋板块北侧集中约70％有各类偏差地震.印度洋板块北侧各项误差统计占全世界同类地震约70％,表现出较好的一致性.这种现象应与震源过程有关,与该地区S波走时异常问题耦合,而不是算法或随机误差造成的.     

钻孔应变观测干扰及异常分析

怀来台体积式钻孔应变仪安装于1988年,以应变固体潮为主要观测目标.多年来,取得了连续完整高质量的观测资料.本文列举了怀来钻孔应变的台址背景及仪器观测条件;分析了实际观测中钻孔应变资料受仪器零漂、气压、水位、降雨等因素的干扰;研究了钻孔应变在本区及邻区震前出现的记录曲线畸变、潮汐因子异常、应变固体潮畸变等不同形式的异常变化并对其进行特征分析.研究表明,钻孔应变观测是获取构造活动异常变化信息,进行地球物理研究、地震预测预报的有效途径.     

太阳活动对中山站F2层峰值电子浓度的影响

利用中山站1995-2006年的电离层垂测数据统计分析了当地电离层F2层峰值电子浓度（N_mF2）对太阳活动变化的依赖性,研究发现在中山站N_mF2月中值随修正太阳10.7厘米通量指数F10.7P增大而增大,其饱和或放大趋势不明显。除冬季12-16 UT、20-2 UT与夏季2-11 UT以外的绝大部分时刻,两者具有良好的线性关系。N_mF2月中值随F10.7P变化斜率随季节、地方时而变化。在日变化中,N_mF2随F10.7P变化斜率极大值出现在磁中午附近,明显大于其他时刻,在夜侧变化斜率整体较小,且在分季和冬季的夜侧以及夏季全天,其斜率随地方时变化不大。在年变化中,日侧斜率最大值出现在两分季,冬季次之,夏季最小;而夜侧斜率在夏半年（10月-3月）整体上要大于冬半年（4月-9月）。结合中山站位于极隙区纬度的特殊地理位置,分析了上述N_mF2变化特征的可能原因。     

Probing deep weathering in the Shale Hills Critical Zone Observatory,Pennsylvania (USA): the hypothesis of nested chemical reaction fronts in the subsurface

Weathering is both an acid‐base and a redox reaction in which rocks are titrated by meteoric carbon dioxide (CO₂) and oxygen (O₂). In general, the depths of these weathering reactions are unknown. To determine such depths, cuttings of Rose Hill shale were investigated from one borehole from the ridge and four boreholes from the valley at the Susquehanna Shale Hills Observatory (SSHO). Pyrite concentrations are insignificant to depths of 23 m under the ridge and 8–9 m under the valley. Likewise, carbonate concentrations are insignificant to 22 and 2 m, respectively. In addition, a 5–6 m‐thick fractured layer directly beneath the land surface shows evidence for loss of illite, chlorite, and feldspar. Under the valley, secondary carbonates may have precipited. The limited number of boreholes and the tight folding make it impossible to prove that depth variations result from weathering instead of chemical heterogeneity within the parent shale. However, carbonate depletion coincides with the winter water table observed at ~20 m (ridge) and ~2 m depth (valley). It would be fortuitous if carbonate‐containing strata are found under ridge and valley only beneath the water table. Furthermore, pyrite and carbonate react quickly and many deep reaction fronts for these minerals are described in the literature. We propose that deep transport of O₂ initiates weathering at SSHO and many other localities because pyrite commonly oxidizes autocatalytically to acidify porewaters and open porosity. According to this hypothesis, the mineral distributions at SSHO are nested reaction fronts that overprint protolith stratigraphy. The fronts are hypothesized to lie subparallel to the land surface because O₂ diffuses to the water table and causes oxidative dissolution of pyrite. Pyrite‐derived sulfuric acid (H₂SO₄) plus CO₂ also dissolve carbonates above the water table. To understand how reaction fronts record long‐term coupling between erosion and weathering will require intensive mapping of the subsurface. Copyright © 2013 John Wiley & Sons, Ltd.     

2018年松原5.7级地震前地磁垂直分量日变化低点时间时空演化特征

本文对松原5.7级地震前地磁垂直分量日变化低点时间时空演化特征进行研究，结果显示：1）以去除经度效应后低点时间为0 h的等值线作为低点位移分界线，松原5.7级地震的震中分别位于2018-04-13分界线上和2018-04-24分界线附近；2）异常日期间，中国大陆地磁垂直分量日变形态存在分区特征，去除经度效应后低点时间为正、负的区域内日变形态分别以“W”型和“V”型为主；3）在2018-04-13和2018-04-24这2个异常日期间，中国大陆都存在去除经度效应后的低点时间高梯度带，松原5.7级地震的震中分别位于2018-04-13高梯度区边缘和2018-04-24高梯度区东侧。