Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

In northern China, the Quaternary loess-soil se-quences[1] and the Hipparion Red-Earth Formation in the eastern Loess Plateau[2―6] provide a continental climate record for the past 8 Ma. The recently reported Miocene[7] and Pliocene[8] loess-soil sequences near Qinan constitute an eolian record of the western Loess Plateau from 22 to 3.5 Ma. Earlier studies[9] place the Miocene loess deposits into the so-called Gansu Sys-tem. Our investigations show that the Gansu System contains inde…     

In situ cosmogenic ~(10)Be dating of the Quaternary glaciations in the southern Shaluli Mountain on the Southeastern Tibetan Plateau

It is generally considered that four-times ice age happened during the Quaternary epoch on the Tibetan Plateau. However, the research on the chronology of the four-times ice age is far from enough. The Shaluli Mountain on the Southeastern Tibetan Plateau is an ideal place for plaeo-glacier study, because there are abundant Quaternary glacial remains there. This paper discusses the ages of the Quaternary glaciations, based on the exposure dating of roche moutonnée, moraines and gla- cial erosion surfaces using in situ cosmogenic isotopes 10Be. It is found that the exposure age of the roche moutonnée at Tuershan is 15 ka, corresponding to Stage 2 of the deep-sea oxygen isotope, suggesting that the roche moutonnée at Tuershan is formed in the last glacial maximum. The expo- sure age of glacial erosion surface at Laolinkou is 130―160 ka, corresponding to Stage 6 of the deep-sea oxygen isotope. The oldest end moraine at Kuzhaori may form at 421―766 kaBP, corre- sponding to Stages 12―18 of the deep-sea oxygen isotope. In accordance with the climate charac- teristic of stages 12,14,16 and 18 reflected by the deep-sea oxygen isotope, polar ice cores and loess sequence, the oldest end moraine at Kuzhaori may form at stage 12 or stage 16, the latter is more possible.     

对豫西南两次历史地震的甄别与复核

历史地震调查是核电厂和大型水利枢纽等重大工程建设场地地震安全性评价的重要内容之一。近来，本文作者在参与完成河南核电项目选址阶段地震安全性评价任务的过程中，曾对豫西南地区的历史地震进行过调查。兹将其中两次较为重要的历史地震的甄别与复核结果介绍如下，希望对相关的研究工作和今后修编地震目录有所裨益。     

郑州市区环境空气污染趋势分析

以2003年郑州市环境空气污染的主要监测指标为依据,分析了郑州市空气污染现状,并根据1994~2003年10年来的监测数据,对空气污染特征和污染趋势进行了分析,结论是:郑州市空气污染在近10年呈下降趋势。     

河南省气象服务短信平台

介绍了河南省气象短信运营平台的特点、结构和各模块的功能。     

COMPARISON OF ON-LINE COUPLED AND CONSTANT TRANSFER SIMULATION METHODS FOR DIRECT RADIATIVE FORCING OF ANTHROPOGENIC SULFATE

1 INTRODUCTION Of three main methods for studying the radiative forcing of anthropogenic sulfate and climatic response on the regional scale, the first is, with given rates for transforming SO2 to sulfate, converting actually released SO2 into sulfate and acquiring the distribution of sulfate by computing transfer equations in the climate model.     

南京地区新近系含膏砂泥地层的发现及其意义

在进行南京市城市立体地质填图试点工作中,经钻探于仙林大学城发现一套新近系含膏砂泥地层,可与六合灵岩山雨花台组沉积地层对比.该地层的发现对于重新认识南京地区某些相类似断陷盆地基岩面之上的松散覆盖层的结构很有意义,对其在环境地质和工程地质中的影响进行了评述.同时,对地下水参与成矿作用进行了初步论述.     

中国早白垩世今鸟类甘肃鸟的蹼足化石

玉门甘肃鸟(Gansus yumenensis)是中国发现的第一只中生代鸟类化石.该化石产自甘肃西北部下沟组,时代与辽宁西部产热河生物群的早白垩世地层的时代大体相当.该鸟类趾节拉长,很短的爪具有较尖锐的屈肌结节,因而被认为是一种适应于水生生活的鸟类.玉门甘肃鸟的建立最初仅依据一件左足标本,直到最近又发现了少量可供进一步研究的新标本.本文描述了一件新的玉门甘肃鸟的完整后肢化石,标本在远端趾节之间显示出清晰的蹼的构造.这为玉门甘肃鸟具有发育足蹼的观点提供了最直接的证据.玉门甘肃鸟也成为世界上已知最古老的适应于水生生活环境的鸟类.     

应用ObjectARX开发土钉支护CAD系统

阐述基于数据库的土钉支护的设计过程。介绍ObjectARX基础知识,并将其应用于土钉支护CAD系统中,成功地对AutoCAD底层数据库进行操作,实现了符合实际工程习惯的土钉支护施工图的绘制。在破坏面的自动搜索上,采取黄金分割法与一维Brent法相结合的方法,很好地实现了自动搜索功能。这一方法不但很好地满足了计算速度的要求,而且也实现了考虑施工阶段边坡分析的目标。     

华北地区两个世代深部构造的识别及其意义——燕山运动与深部过程

通过对华北地区地震层析成像成果的研究，将其深部构造划分为三带：①大型软流圈上涌柱带，主要出现两个大型软流圈上涌柱；②过渡带，呈现4个小型软流圈上涌柱（软块）与岩石圈较厚区（硬块）相间的构造格局；③巨厚岩石圈带，为巨厚岩石圈（鄂尔多斯硬块）稳定区。依据岩石圈热力学衰减原理，一定体积的深部构造可存留200～300Ma之久，而传导人浅表的热量则扩散较快。故以大地热流值为主，结合浅层岩浆活动可将本区中生代与新生代的软流圈上涌柱区分开来：渤海湾柱、大同柱和南阳柱属新生代，邯郸柱、中条柱和吕梁柱则属于中生代燕山期。在此基础上，建立了燕山期深部构造与浅表岩浆构造活动关系的模式：在强大的分散热力作用下，软流圈上涌柱柱头中大量热浮物质向上熔蚀薄的岩石圈及下地壳，混染而主要形成中酸性岩及有关矿产；而在软流圈上涌柱与岩石圈的陡接触处，由于该处热力集中，致使幔源物质底侵下地壳，并再熔融上侵形成偏碱性-碱性杂岩及相应矿产。