北京及其周围地区重力重复测量资料的研究

针对北京及其周围地区重复重力测量资料所进行的重力非潮汐信息的处理程式，对该区１９８４－１９８８年期间重力变化机制进行了研究。结果表明，地下水位的变化是１９８４－１９８８年期间北京及其周围地区影响重力重复测量的主要因素。校正后的重力资料显示出，１９８７－１９８８年在北京以西地区策略变化比东部地区的变化幅值大。据分析，这种变化可作为研究１９８９年大同地震的地震孕育场依据之一。     

郫县重力异常与四川近年地震关系的震例分析

本文介绍了容量限制分配方法的概念、交通量与车速的特点、容量限制分配方法的具体应用步骤和分配次数对分配结果的影响等。     

大同地区几次中强震前后的重力变化

本文对华北北环重力重复测量资料进行了分析研究，探讨了排除浅层干扰因素，提取与地震相关的重力变化的途径。以大同地震为例，详细分析了地震前后重力场变化，结果表明，其变化是明显的，远远超过了各项误差。     

铜镍硫化物矿床成矿理论的新进展

岩浆深部液态重力分异成矿作用、岩浆同化混染成矿作用、矿浆成矿作用、岩浆分离结晶作用和热液作用对铜镍硫化物成矿有重要影响。岩浆深部液态重力分异成矿作用是原始含矿岩浆产生多样性岩浆和铜镍等成矿元素原始富集的重要原因,矿浆成矿作用则与岩浆深部液态重力分异成矿作用密切相关,是含矿岩浆成矿过程中的特殊地质事件。     

滇中地区晚三叠世的重力流沉积及其地质意义

上三叠统云南驿组一段下部是钙质浊积岩,上部为陆源碎屑浊积岩及少量火山碎屑浊积岩;二段的角砾状灰岩有坍塌和重力滑动两种成因,夹钙质浊积岩。罗家大山组一段由火山碎屑质的碎屑流、浊流和颗粒流沉积组成,夹基性熔岩。它们是滇中裂谷的记录,物源区在西边,构成中国西南部三叠纪古特提斯的一部分。     

融合GOCE和GRACE卫星数据的无约束重力场模型Tongji-GOGR2019S

本文在法方程层面融合GOCE卫星的V_xx、V_yy、V_zz和V_xz重力梯度分量观测数据和GRACE卫星观测数据,采用直接法解算了220阶次的重力场模型Tongji-GOGR2019S.首先利用ⅡR带通滤波器在5~41 mHz的重力梯度带宽范围内对约24个月的GOCE重力梯度观测方程进行无相移滤波处理,并组成解算220阶次重力场模型的法方程,各梯度分量根据相对于参考模型统计精度进行定权;然后与13.5 a GRACE数据建立的180阶次Tongji-Grace02s重力场模型的法方程进行叠加,解算了220阶次的无约束纯卫星重力场模型Tongji-GOGR2019S.利用EIGEN-6C4重力场模型、GNSS/水准数据、DTU15重力异常数据以及欧洲区域似大地水准面模型EGG2015等数据对Tongji-GOGR2019S模型精度进行全面的检核评定,结果表明：引入GOCE卫星梯度数据后,高于72阶的位系数精度优于Tongji-Grace02s模型,Tongji-GOGR2019S模型的整体精度接近同阶次的DIR-R6等GOCE卫星第6代模型.     

羌塘盆地中央隆起带的重磁场证据及其构造意义

对于羌塘盆地是否存在横贯东西的中央隆起带,目前学术界仍有分歧.本文提供的最新高精度航空重、磁资料证实存在呈东西向贯通羌塘盆地的中央隆起带,并对该带的构造特征进行了精细刻画.隆起带受南北两侧深大断裂控制,其空间跨度（宽度）由西向东逐渐收敛,并被一组近南北向的隐伏断裂系切割、左滑错动.重、磁场资料还显示中央隆起带在双湖东、西两侧存在明显差异：西段基底大规模隆起,基岩深度一般在3~5 km以内,明显浅于南北羌塘坳陷7~15 km的基底埋深;东段基底隆起幅度明显降低,主要表现为潜伏的低隆起,其中双湖—雅曲段基底埋深5~7 km,雅曲—岗尼段基底埋深7~9 km;即中央隆起带基底自西向东"台阶状"降低,隆起的幅度和分布范围受到近南北向断裂控制.构造分层表明,与南羌塘地块相比,北羌塘地块的基底隆起幅度小、稳定性更好.南北羌塘基底地球物理属性的显著差异说明羌塘盆地并不存在统一的前寒武系变质基底,中央隆起带的形成应该与古特提斯洋关闭时形成的混杂岩带有关.     

2-D Crustal Velocity Structure Along Hirapur-Mandla Profile in Central India: An Update

The 2-D crustal velocity model along the Hirapur-Mandla DSS profile across the Narmada-Son lineament in central India (Murty et al., 1998) has been updated based on the analysis of some short and discontinuous seismic wide-angle reflection phases. Three layers, with seismic velocities of 6.5–6.7, 6.35–6.40 and 6.8 km s^–1, and upper boundaries located approximately at 8, 17 and 22 km depth respectively, have been identified between the basement (velocity 5.9 km s^–1) and the uppermost mantle (velocity 7.8 km s^–1). The layer with 6.5–6.7 km s^–1 velocity is thin and is less than 2-km deep between the Narmada north (at Katangi) and south (at Jabalpur) faults. The upper crust shows a horst feature between these faults, which indicates that the Narmada zone acts as a ridge between two pockets of mafic intrusion in the upper crust. The Moho boundary, at 40–44 km depth and the intra-crustal layers exhibit an upwarp suggesting that the Narmada faults have deep origins, involving deep-seated tectonics. A smaller intrusive thickness between the Narmada faults, as compared to those beyond these faults, suggests that the intrusive activities on the two sides are independent. This further suggests that the two Narmada faults may have been active at different geological times. The seismic model is constrained by 2-D gravity modeling. The gravity highs on either side of the Narmada zone are due to the effect of the high velocity/high density mafic intrusion at upper crustal level.     

Gravity and Inertia-Gravity Internal Waves: Breaking Processes and Induced Mixing

Internal gravity waves, whether influenced or not by the Earths rotation, are ubiquitous dynamical features in the stratosphere and in the interior of the ocean. We review the mechanisms by which such waves may break when propagating in an infinite (possibly moving) fluid with uniform stratification. The methods and models used to quantify mixing in a stably-stratified fluid are next recalled. The mixing properties induced by the breaking waves as obtained from several field, experimental and numerical experiments reported in the literature are presented.