FY-3A/MERSI海上沙尘天气气溶胶光学厚度反演

利用FY-3A/MERSI资料,结合MODIS C005算法的海上气溶胶模型,研究了中国渤海、黄海以及东海海域沙尘天气气溶胶光学厚度反演方法。通过MERSI反演的气溶胶光学厚度与MODIS C005气溶胶光学厚度产品(MOD04)对比,发现MERSI气溶胶光学厚度反演结果存在较大偏差。分析认为,这种偏差是由MODIS C005算法的海上气溶胶模型对MERSI气溶胶光学厚度反演不完全适用造成的。鉴于此,本文研究引进了一种沙尘气溶胶模型,并将其与MODIS C005算法的粗粒子气溶胶模型按照一定比例混合,形成了改进的气溶胶模型。利用改进气溶胶模型再次反演海上沙尘天气气溶胶光学厚度,反演结果与MOD04一致性较好,说明改进气溶胶模型能有效地提高MERSI定量反演沙尘气溶胶的能力。     

Impact of SARAL/AltiKa-Derived Sea Level Anomaly in a Data Assimilative Ocean Prediction System for the Indian Ocean

The impact of SARAL/AltiKa derived sea level anomaly (SLA) has been studied by assimilating it along with Jason-2 and Cryosat-2 SLA in the Princeton Ocean model (POM) using ensemble optimal interpolation (EnOI) technique. For isolating the extra benefit brought by SARAKL/Altika, a parallel run with assimilation of only Jason-2 and Cryosat-2 SLA has also been conducted. The importance of SARAL SLA in a data assimilative ocean prediction system has been evaluated with special emphasis on the improvement in thermocline depth, depth of the 20° isotherm, subsurface temperature and currents. Comparison with RAMA buoy has shown a positive impact of up to 13% for 20°C isotherm and up to 17% for thermocline depth after assimilating SARAL SLA. An overall improvement in temperature profile is also observed when compared with analogous profiles from RAMA buoys and Argo floats. Improvement in zonal currents away from the equator has also been noticed.     

鲁西归来庄金矿床深部外围找矿前景

鲁西地区归来庄金矿床找矿始于1987年初,历经"六进六出"的坚持不懈,探求金金属量34.8t,填补了鲁西地区无大型金矿的空白。近几年,山东省鲁南地质工程勘察院在归来庄金矿床深部及外围开展的勘查工作,扩大了归来庄主矿体的规模,并且证实归来庄主矿体沿F1构造蚀变带向深部尚未封闭,仍有良好找矿前景。目前归来庄金矿累计探明金金属量超过50t,是鲁西地区唯一的特大型金矿床。该文在系统分析以往成果资料基础上,系统归纳了归来庄主矿体地质特征,建立了铜石杂岩体周边多种金矿化类型"一体多型"成矿模式,指出了下步找矿方向:归来庄金矿床深部找矿仍以寻找隐爆角砾岩型为主,外围重点围绕"一带多区",争取早日实现铜石地区找矿新突破。     

稀疏采样下陡角度构造的波动方程深度偏移成像

针对稀疏采样,特别是crossline方向稀疏采样的三维地震数据,提出了一个基于波动方程方法的陡角度构造深度偏移成像方法.文中针对一类混合域（空间和波数）的波动方程偏移方法展开研究.通过建立反假频的单程波算子和通过（形式上）填充空道重建理想采样的地震数据,有效地实现了陡倾角地层的准确成像.这一算法策略解决了波动方程偏移方法在实际应用中的一个关键问题,从而更好地发挥了波动方程偏移方法在复杂构造成像上的优势.二维理论数据（Marmousi模型）和三维实际地震资料成像结果表明本文方法是有效的.这一方法对现行的三维地震数据处理有重要的现实意义.     

The application of high-resolution 3D seismic data to model the distribution of mechanical and hydrogeological properties of a potential host rock for the deep storage of radioactive waste in France

In the context of a deep geological repository of high-level radioactive wastes, the French National Radioactive Waste Management Agency (Andra) has conducted an extensive characterization of the Callovo-Oxfordian argillaceous rock and surrounding formations in the Eastern Paris Basin. As part of this project, an accurate 3D seismic derived geological model is needed. The paper shows the procedure used for building the 3D seismic constrained geological model in depth by combining time-to-depth conversion of seismic horizons, consistent seismic velocity model and elastic impedance in time. It also shows how the 3D model is used for mechanical and hydrogeological studies. The 3D seismic field data example illustrates the potential of the proposed depth conversion procedure for estimating density and velocity distributions, which are consistent with the depth conversion of seismic horizons using the Bayesian Kriging method. The geological model shows good agreement with well log data obtained from a reference well, located closest to the 3D seismic survey area.Modeling of the mechanical parameters such as shear modulus, Young modulus, bulk modulus indicates low variability of parameters confirming the homogeneity of the target formation (Callovo-Oxfordian claystone). 3D modeling of a permeability index (Ik-Seis) computed from seismic attributes (instantaneous frequency, envelope, elastic impedance) and validated at the reference well shows promising potential for supporting hydrogeological simulation and decision making related to safety issues.     

多种方法测定广东阳西3.7级地震震源深度

应用CAP和深度震相方法,对2018年3月20日发生在广东阳西的M3.7级地震震源深度进行了测定。首先通过CAP方法反演获得震源机制解,拟合最佳震源深度为12km。然后在震中距100km以内的近台识别出清晰的sPL和PmP、sPmP震相,利用频率-波数(F-K)方法,计算出深度震相在不同深度下的理论地震图,与实际观测波形对比测定震源深度为12km。再利用250~400km震中距范围内台站上识别出的sPn与Pn震相的走时差,测得震源深度12.6km。多种方法的研究结果一致,表明该地震震源深度为12km比较可靠。     

阜阳M_S4.3地震震源深度的确定及地震成因分析

2015年3月14日在安徽阜阳地区发生了M_S4.3地震,随后发生3月23日M_s3.6余震.主震造成2人死亡13人受伤.房屋倒塌155间,受损1万多间.主震震级不大,而造成的灾害巨大.本文使用CAP方法反演了两次地震的震源机制解和震源深度,结果显示两次地震的震源机制解和深度一致.主震的机制解节面Ⅰ走向110°,倾角75°,滑动角—10°;节面Ⅱ走向202°,倾角80°,滑动角—164°;矩震级M_w4.3,余震矩震级M_w3.7,反演最佳深度均为3 km.最佳深度时波形拟合相关系数较高,表明反演结果是可靠的.使用sPn和sPL深度震相进一步分析了两次地震的震源深度.结果显示,选取的7个台站的sPn震相与Pn震相的平均到时差为1 s,对应的震源深度为3 km.震中距为36 km的利辛台的sPL震相与Pg震相到时差约为1.1 s,对应震源深度约3~4 km之间.两种深度震相分析的震源深度与CAP方法的结果一致,表明本文给出的阜阳地震震源深度为3 km左右基本是可靠的.本次地震造成较大灾害的原因很可能与地震震源较浅有关.阜阳地区地壳结构相对稳定,地质构造演化形成3 km厚的沉积层,本次地震可能是区域应力作用下发生在沉积层里的一次地震.     

波场延拓深度滤波方法

消除面波是地震数据处理中的一个重要内容．本文提出了基于15°波动方程的深度滤波方法．由于面波与有效反射波具有不同的传播深度,可利用波场向下延拓方法将二者进行波场分离．把向下延拓后的波场中集中在地表附近的面波能量切除后,再将波场重新延拓回原始的观测面,达到去除干扰的目的．实际资料处理显示：方法计算稳定,消除面波能力强,能更好地保持波场的有效成份和幅值,符合波场的实际传播状态,表明该方法正确可行．     

花岗岩类源岩与深部地质作用关系研究的若干进展

花岗岩类源岩研究是成岩成矿物质演化过程研究的基础,各种各样花岗岩的存在归因于花岗岩源岩存在多样性,在不同层圈发生交代,熔融,同化,混染作用;同时,成矿元素亦存在不同深度层圈的多来源,在花岗岩成岩成矿过程中,岩石圈地幔起着重要作用。