中国黄土与红色粘土记录的地磁极性界限及地质意义

本文报道由蓝田、陕县、洛川、西峰、平凉、兰州及靖远等剖面获得的古地磁研究结果．主要结论为：１．中国黄土剖面记录了Ｂｒｕｎｈｅｓ正极性带与Ｍａｔｕｙａｍａ负极性带，Ｂｒｕｎｈｅｓ／Ｍａｔｕｙａｍａ极性转换过程位于第８层黄土（Ｌ８）．在段家坡黄土剖面该转换过程对应的地层厚度为０．３７５ｍ，持续时间约６０００ａ．转换过程由３次极性变化构成，每次经历的时间约为４００ａ．２．Ｊａｒａｍｉｌｌｏ正极性亚带（Ｊ）位于标志层Ｌ９至Ｌ１５之间，大约Ｓ１０－Ｓ１３位置．３．Ｏｌｄｕｖａｉ正极性亚带（Ｏ）对应的地层为Ｓ２７－Ｓ３３４．Ｒｅｕｎｉｏｎ正极性亚带（Ｒ）由两部分组成，在蓝田段家坡黄土剖面分别位于Ｌ３６和Ｓ３８５．Ｍａｔｕｙａｍａ负极性带与Ｇａｕｓｓ正极性带界限（Ｍ／Ｇａ）位于黄土和红色粘土交界处，中国黄土的底界年龄为２．４８Ｍａ左右．黄土与红色粘土为整合接触关系．６．黄土下伏的红色粘土记录了Ｇａｕｓｓ正极性带，Ｇｉｌｂｅｒｔ负极性带和古地磁年表编号５（Ｅｐｏｃｈ５）．     

基于小波变换的GPS周跳探测

概述了GPS周跳产生的原因及其探测周跳的重要性，总结了用来进行检测的常用方法，重点讨论了用小波分析来检查周跳的基本思想。并用实际的工程算例验证了该方法的可行性和有效性。     

Isolation and biological characteristics of aerobic marine magnetotactic bacterium YSC-1

1 INTRODUCTION Magnetotactic bacteria are able to respond and orient along the direction of terrestrial or artificial magnetic field, a behavior referred to as magneto- taxis. In the majority of magnetotactic bacteria, the magnetosomes are 25–120 nm in d…     

武汉钰龙金融广场超深基坑工程设计方案选型

以武汉钰龙金融广场超深基坑工程为实例,在结合常用的深基坑设计方案的基础上分别从基坑总体设计方案选定、基坑围护体系选定和设计、支撑体系选定、基坑降水选定、土方开挖方案选型和换撑方案的选定等方面进行探讨,并确定最终的基坑工程设计方案选型,即地下连续墙围护+3道内支撑+管井降水处理承压水的支护方案。     

Petrology and PGE Abundances of High‐Cr and High‐Al Podiform Chromitites and Peridotites from the Bulqiza Ultramafic Massif,Eastern Mirdita Ophiolite,Albania

The Bulqiza ultramafic massif, which is part of the eastern Mirdita ophiolite of northern Albania, is world renowned for its high-Cr chromitite deposits. High-Cr chromitites hosted in the mantle section are the crystallized products of boninitic melts in a supra-subduction zone (SSZ). However, economically important high-Al chromitites are also present in massive dunite of the mantle-crust transition zone (MTZ). Chromian-spinel in the high-Al chromitites and dunites of the MTZ have much lower Cr# values (100Cr/(Cr+Al)) (47.7–55.1 and 46.5–51.7, respectively) than those in the high-Cr chromitites (78.2–80.4), harzburgites (72.6–77.9) and mantle dunites (79.4–84.3). The chemical differences in these two types of chromitites are reflected in the behaviors of their platinum-group elements (PGE). The high-Cr chromitites are rich in IPGE relative to PPGE with 0.10–0.45 PPGE/IPGE ratios, whereas the high-Al chromitites have relatively higher PPGE/IPGE ratios between 1.20 and 7.80. The calculated melts in equilibrium with the high-Cr chromitites are boninitic-like, and those associated with the high-Al chromitites are MORB-like but with hydrous, oxidized and TiO2-poor features. We propose that the coexistence of both types of chromitites in the Bulqiza ultramafic massif may indicates a change in magma composition from MORB-like to boninitic-like in a proto-forearc setting during subduction initiation.     

Molybdenum Polymetallic Metallogenic Regularity and Metallogenic Prediction of the Jinduicheng-Huang Longpu Mineral Field,Shanxi Provice

Please refer to the attachment(s) for more details     

机械扩大头锚索在成都膨胀土地区深基坑支护中的应用

在膨胀土地区进行基坑支护设计时,常规的桩锚支护体系受到很大限制。以成都膨胀土地区某深基坑支护工程为例,根据本工程特点,综合考虑安全、经济、效率、环保等因素,确定采用机械扩大头锚索+排桩型式进行支护,并对方案选型、施工关键技术、现场试验等过程进行了详细的介绍,通过监测结果的验证,阐明该扩大头锚索支挡结构体系能够很好地适应膨胀土的特殊地质条件及复杂的周边环境,具有极好的推广价值,为今后类似工程的建设提供一定的参考和借鉴。     

Wind impact on pollutant transport in a shallow estuary

A three-dimensional numerical model, EFDC （ environmental fluid dynamics code） is applied to the Pamlico River Estuary （PRE） in eastern North Carolina of the United States to examine the wind impact on pollutant age distributions and residence time. A series of model experiments representing base case, remote-wind-induced water level set-up and local winds cases are conducted. Model results indicate that the pollutant mean age and the system residence time are functions of gravitational circulation in the PRE. The system responses to remote-wind-induced water level set-up are different in different portions of the PRE. Under such condition, dissolved substances in the upstream portion of the PRE have a younger age and shorter residence time （compared with the base case） , by contrast, they have a older age and longer residence time in the downstream portion of the PRE. Upriver and downriver local winds appear to have opposite impacts on pollutant age distributions. The substances are retained much longer within the PRE under upriver wind than those under downriver wind. The model results also suggest that across - river winds may lead to longer residence time through enhanced turbulence mixing, which slows down the gravitational circulation in the PRE.     

四川省上市公司可持续发展财务问题分析

财务指标是企业盈利能力的反映。根据近几年的相关数据,通过对财务指标综合分析,探讨四川省上市公司的可持续发展状况。