地震过程中的大地电场变化特征

根据国产ZD9A型大地电场仪在宝低地电台的记录结果,研究了1998年1月10日河北省张北地区6．2级地震过程中的大地电场变化特征．主要表现为：1．震前36天至发震当日出现大地电场日变异常簇;2．地震前后大地电场E的方位发生转动;3、大地电场E具有日变倍9（天）周期性和振幅｜E｜变化特征;4大地电场EW分量的极性变化．根据对这些特征的分析结果表明,它们有可能做为孕震进入短临阶段的前兆信息及识别标志．     

1983年山东菏泽5.9级地震地下流体异常的检验性预测

本文对１９８３年山东菏５．９级地震震中周围２００ｋｍ范围内８口井１７个测地下流体观测资料,采用地下流体群体异常演化层次跟踪法,对菏治５．９级地震进行了中期,短期和短临三个时间尺度的震情预测,     

Isolated Archosaur teeth from the green sandstone capping the Coralline Limestone (Bagh Group) of the Narmada valley: Evidence for the presence of pre‐Late to Late Maastrichtian abelisaurids in India

Recent field prospecting in the Cretaceous sequences of the lower Narmada valley has led to the discovery of three isolated archosaur teeth from the upper part of marine Cretaceous rocks of the Bagh Group. The specimens were recovered by surface prospecting from an oyster‐bearing green sandstone bed occurring at the top of the Coralline Limestone (Coniacian) from a site near Phutibawri village, Dhar District, Madhya Pradesh, India. Of the three teeth recovered from this horizon, two are identified with abelisaurid dinosaurs and the third one with an indeterminate crocodile. The abelisaurid teeth conform to the premaxillary and maxillary tooth morphology of Majungasaurus and Indosuchus. Earlier reports of abelisaurid dinosaurs from India are from the Upper Cretaceous (Maastrichtian) Lameta Group of Jabalpur, Pisdura (Central India) and Balasinor (Western India) and Upper Cretaceous (Late Maastrichtian) Kallamedu Formation (South India). As no associated age diagnostic fossils are found, the specimens described here are considered to represent pre‐Late to Late Maastrichtian age based on the known ages of the underlying and overlying formations. The new finds, therefore, document stratigraphically the oldest occurrence of abelisaurid dinosaurs known from the Indian subcontinent.     

Trace analysis of quaternary aminoalcohols as degradation products from softeners in wastewater

The sensitive and selective determination of polyalcohols without chromophores or fluorophores in the lower ppb-level is still an analytical task of high interest, especially in the field of environmental investigations. This paper describes a cation-exchange HPLC procedure for the separation and fluorescence detection of two quaternary ammonium compounds with polyalcoholic groups (degradation products of fabric softener) after derivatization with 9-fluorenylmethyl chloroformate (FMOC). Detailed experiments were carried out to determine optimum reaction conditions (pH, reaction time, temperature), linear range, detection limits, and kinetics of the reaction. The HPLC separation on a cation-exchange column includes a gradient program which provides complete separation from neutral compounds also reacting with FMOC and its hydrolysis products formed during the reaction in alkaline medium. High specificity for both investigated ammonium compounds with detection limits in the range of 1 ppb could be achieved.     

加强科学管理是“九五”重点项目顺利实施的重要保障

本文对辽宁省防震减灾“九五”重点项目实施过程中采取的管理体制及管理措施进行了介绍。在管理体制上 ,建立了较为完善的组织机制构 ,按照全省地震系统一盘棋的指导思想 ,把市地震局作为一级管理机构 ,由市地震局负责本地区项目的实施与组织管理工作 ;在项目管理中 ,采取了跟踪检查、抓样板示范、抓项目施工质量、抓创新、抓技术培训等行之有效的措施 ,为“九五”重点项目的顺利完成并取得较好成绩提供了保证     

Chemical characteristics of the crater lakes of Popocatetetl, El Chichon, and Nevado de Toluca volcanoes, Mexico

Three crater lakes from Mexican volcanoes were sampled and analyzed at various dates to determine their chemical characteristics. Strong differences were observed in the chemistry among the three lakes: Nevado de Toluca, considered as dormant, El Chichón at a post-eruptive stage, and Popocatépetl at a pre-eruptive stage. Not surprisingly, no influence of volcanic activity was found at the Nevado de Toluca volcano, while the other volcanoes showed a correlation between the changing level of activity and the evolution of chemical trends. Low pHs (<3.0) were measured in the water from the active volcanoes, while a pH of 5.6 was measured at the Nevado de Toluca Sun lake. Changes with time were observed at Popocatépetl and El Chichón. Concentrations of volcanic-gas derived species like Cl⁻, SO₄²⁻ and F⁻ decreased irregularly at El Chichón from 1983 until 1997. Major cations concentrations also diminished at El Chichón. A 100% increase in the SO₄²⁻ content was measured at Popocatépetl between 1985 and 1994. An increase in the Mg/Cl ratio between 1992 (Mg/Cl=0.085) and 1994 (Mg/Cl=0.177) was observed at Popocatépetl, before the disappearance of the crater lake in 1994. It is concluded that chemical analysis of crater lakes may provide a useful additional tool for active-volcano monitoring.     

The prediction for seismicity trends of M≥8 in the world by analysis of seismicity patterns

After completion of a study on predicting risky zones of earthquake of M≥8 for 1-3 years in the mainland of China,which was supported by Chinese Joint Seismological Science Foundation(D07018 and D08009),a further study was extended to that of greater magnitudes in the world.Based on the historical earthquake cases,we finished the research report,forecasting global earthquakes with magnitude more than 8.0 using the image analysis of seismicity.In this research report,we summarize 11 abnormal seismicity images for predicting earthquake of M≥8.0 around the world.In our research report,we predicted earthquakes of M≥8.0 from June 2009 to June 2014,the medium term predicting within 5 years period.Among these 5 predictive areas,three earthquakes occurred,which is Samoa M8.1 Earthquake on 29 September 2009,Talca M8.5 Earthquake on 27 January 2010,Chile,and Eastern Sendai M9.0 Earthquake on 11 March 2011,Japan respectively.Here we introduce the main items of the image analysis of seismicity and we predict three earthquakes and think that the image analysis of seismicity can be of help.     

HP–LT Variscan metamorphism in the Cubito-Moura schists (Ossa-Morena Zone, southern Iberia)

Multi-equilibrium thermobarometry shows that low-grade metapelites (Cubito-Moura schists) from the Ossa–Morena Zone underwent HP–LT metamorphism from 340–370 °C at 1.0–0.9 GPa to 400–450 °C at 0.8–0.7 GPa. These HP–LT equilibriums were reached by parageneses including white K mica, chlorite and chloritoid, which define the earliest schistosity (S₁) in these rocks. The main foliation in the schists is a crenulation cleavage (S₂), which developed during decompression from 0.8–0.7 to 0.4–0.3 GPa at increasing temperatures from 400–450 °C to 440–465 °C. Fe³⁺ in chlorite decreased greatly during prograde metamorphism from molar fractions of 0.4 determined in syn-S₁ chlorites down to 0.1 in syn-S₂ chlorites. These new data add to previous findings of eclogites in the Moura schists indicating that a pile of allochtonous rocks situated next to the Beja-Acebuches oceanic amphibolites underwent HP–LT metamorphism during the Variscan orogeny. To cite this article: G. Booth-Rea et al., C. R. Geoscience 338 (2006).     

复杂线-线对象的拓扑关系描述与计算方法

空间拓扑关系是GIS中空间查询和分析的基础。针对当前空间拓扑关系模型在表达较复杂对象间拓扑关系存在局限性的突出问题,以线对象为实例,根据点集拓扑理论,重新定义和区分线对象的复杂性;以9I模型为基础,提出一种适合二维复杂线对象的拓扑关系的线性序列描述模型,将复杂线-线的拓扑关系表示成基本拓扑关系的组合。分析不同情形下线之间拓扑关系不同的计算方法。为实现复杂线-线拓扑关系的计算,提高扫描线算法的效率,探讨包络矩形粗滤、线节点重合或共线的斜率坐标判断法等改进方法,提出判断线-线是否相交的矢量叉乘法,具有快速高效的特点。最后,通过实验系统导入线坐标串,进行图形绘制、拓扑关系计算并输出结果,从而验证该模型和算法的可行性。     

High‐Precision Measurement of 187Os/188Os Isotope Ratios of Nanogram to Picogram Amounts of Os in Geological Samples by N‐TIMS using Faraday Cups Equipped with 1013 Ω Amplifiers

N(¹⁸⁷Os)/N(¹⁸⁸Os) ratios of six geological reference materials were measured using static Faraday cups (FCs) with 10¹³ Ω amplifiers by N‐TIMS. Our results show that the repeatability precision was 2–3‰ (2 RSD, n = 3), when taking ~ 1 g of BHVO‐2 with 76 pg g^?1 of Os mass fraction and ~ 2 g of BCR‐2 with 21 pg g^?1 of Os mass fraction for each sample, whether measured by FCs or by secondary electron multiplier. The repeatability precision measured by FCs was 1–0.2‰ (2 RSD, n = 3) when taking ~ 1 g of BIR‐2 with 350 pg g^?1 of Os mass fraction, ~ 1 g of WGB‐1 with 493 pg g^?1 of Os mass fraction or ~ 0.5 g of WPR‐1 with 13.3 ng g^?1 of Os mass fraction for each sample, which is much better than those measured by secondary electron multiplier. Instead, when taking ~ 2 g of AGV‐2 with 4 pg g^?1 Os mass fraction, the repeatability precision measured by secondary electron multiplier is 3–4‰ (RSD, n = 3), which is better than those measured by FCs. Of the six reference materials analysed, WPR‐1 and BIR‐1a are the most homogeneous with regard to Os isotopic composition (2 RSD of 0.08% and 0.23%, respectively) when test portion masses are 0.5–1 g.