http://www.sciencedirect.com/science/article/pii/S1674987111000612

Most metallic mineral deposits formed from hydrothermal fluids,and the mineralization processes include both chemical (e.g.,fluid-rock and fluid-fluid interactions) and physical (e.g.,fluid flow) aspects.More attention has been paid to the chemical processes than the physical ones,even though the latter is equally important in controlling the formation of mineral deposits and their localization.Nevertheless,a number of studies have been carried out regarding the hydrodynamics of fluid flow associated with ore mineralization (e.g.,Cathles,1981,1997;Garven and Raffensperger,1997;Cathles and Adams,2005;Cox,2005;Ingebritsen et al.,2006),and it is timely to evaluate our current understanding on this topic and gaps in knowledge to be addressed in further studies.This special section on “Hydrodynamics of mineralization” contains four papers (Chi and Xue,2011;Xue et al.,2011;Zhang et al.,2011;Ju et al.,2011),which summarize the current status of study in the field,and present a few case studies to highlight the importance of hydrodynamics in the research of mineral deposits.     

2022年春季冰雹灾害对贵州西部红心猕猴桃的影响分析

2022年4月下旬至5月上旬,贵州西部共发生了6次冰雹天气过程,有4次冰雹灾害天气严重影响贵州西部红心猕猴桃生产,其主要是发生在4月22日、5月6日、5月8日、5月9日的冰雹天气过程。为了探明2022年4月下旬至5月上旬4次冰雹天气过程对红心猕猴桃果实的影响,通过6次冰雹天气过程影响区的调查,获取冰雹特征数据和红心猕猴桃在4次冰雹灾害过程中的受灾情况,分析诱发冰雹天气发生的大气环流特征,并采用相关统计方法对4次冰雹灾害对红心猕猴桃造成的损失进行评估。结果表明：6次冰雹天气过程中,冰雹最大直径达20mm,但最大直径大多在10mm以下,其中水城区的冰雹最大直径较其他地区大,遭遇冰雹天气次数也最多。影响红心猕猴桃生产的4次冰雹天气过程的天气背景具有贵阳站的CAPE均远远大于威宁站、中低层相对湿度均在90%以上、中高层相对湿度均在80%左右的共同特点。4月22日、5月6日和5月9日冰雹天气发生前,500hPa均有浅槽、700hPa均有低涡切变线入侵贵州西部;5月8日冰雹天气发生前,500hPa和700hPa贵州西部均处于西太副高外围。4次冰雹灾害造成红心猕猴桃885.4hm²绝收,占其基地种植面积的9.04%;因冰雹灾害造成产量损失约1.33万t,直接经济损失19921.5万元。     

Application of AdaBoost Algorithms in Fe Mineral Prospectivity Prediction: A Case Study in Hongyuntan–Chilongfeng Mineral District,Xinjiang Province,China

Natural Resources Research - Continuous resource supply is one of the key points to improve comprehensive national strength. Resource prediction models supportive of target delineation for...     

福建将乐廖家地泥石流灾害调查及防治措施

通过将乐县大源乡廖家地村泥石流灾害现场调查及遥感解译,对该泥石流灾害基本特征、爆发因素进行探讨.根据此次泥石流具有群发性、突发性和破坏性等特点,分析形成泥石流的影响因素,提出相应的防治措施.     

Seismic self‐centering steel beam‐to‐column moment connections using bolted friction devices

This paper first presents the force–deformation relationship of a post‐tensioned (PT) steel beam‐to‐column connection constructed with bolted web friction devices (FDs). This paper then describes the test program conducted in the National Center for Research on Earthquake Engineering, Taiwan, on four bolted FDs and four full‐scale PT beam‐to‐column moment connection subassemblies using the FDs. Tests confirm that (1) the hysteretic behavior of four bolted FDs is very stable, (2) the friction coefficient between the steel plate and the brass shim is about 0.34, (3) the proposed force–deformation relationships reasonably predict the experimental responses of the PT connections under cyclically increasing deformations up to a beam peak rotation of 0.05 rad, and (4) the decompression moments do not degrade as beam cyclic deformations increase. Copyright © 2007 John Wiley & Sons, Ltd.     

围垦工程引起多年海岸冲淤演变的经验计算方法

提出了一个改进的经验公式,用以计算围垦工程引起的淤泥质海岸多年冲淤演变。该经验公式假定在年时间尺度上,地形变化与潮流场变化具有密切联系。引入了一个冲刷折减系数,将传统公式的适用范围从淤积计算拓展到可以同时计算冲刷和淤积。建立了冲淤率年际变化与水深变化之间的关系式,可节省计算时间。将改进公式应用于江苏沿海小庙洪水道,较好地复演了边滩围垦工程影响下周边地形在3年时间内的演变,表明所改进的公式具有一定的可靠性。     

China’s component borehole strainmeter network

In 2004,China’s digital seismic observation network project began to deploy 40 sets YRY-4 four-component borehole strainmeters in order to monitor earthquake preparation process.The paper describes observed solid tidal strain discreteness and tidal factor anisotropy,analyzes the reliability of observational data and discusses the cause for this phenomenon.After getting rid of interferences,the network,in two years practice,has observed several pre-seismic strain anomalies at stations close to epicenters esp...     

东半球空间环境地基综合监测子午链简介

“东半球空间环境地基综合监测子午链”（简称子午工程）是我国空间科学领域开工建设的第一个国家重大基础设施项目。子午工程利用沿东半球120°E子午线附近和北纬30°N附近的15个综合性观测台站,运用无线电、地磁、光学和探空火箭等多种探测手段,连续监测地球表面20—30km以上到几百公里的中高层大气、电离层和磁层,以及十几个地球半径以外的行星际的空间环境参数。它将为我国各类用户提供完整、连续、可靠的多学科、多层次的空间环境地基综合监测数据。子午工程总投资1．67亿元,建设期3年,子午工程整体科学寿命预计超过11年。     

形变标定格值计算软件

为提高地壳形变观测仪器格值标定的真实性、准确性和可靠性,根据《地震前兆台网运行管理办法》和《地震前兆台网形变观测与运行工作细则》,针对不同测项、不同仪器标定的规范要求及特点,应用Visual Basic语言编制了格值计算软件。本文主要介绍了软件的使用、格值计算、误差检查方法,结果以全国形变台网中心推荐的Word格式保存。对水管仪、水平摆、垂直摆仪直接从原始文件读取数据,提高了标定精度,实现了格值标定的半自动化。本软件已应用于河北省地震前兆数字化台站工作。     

利用量子力学势能数据预测温度、压力、盐度和沉积物孔径对甲烷水合物形成和分解的影响

介绍一个预测不同温度、压力、盐度和沉积物毛细管孔径条件下甲烷水合物 溶液 气体多相平衡模型。该模型以Van der Waals和 Platteeuw热力学模型、量子力学从头算粒子相互作用势能、DMW 92状态方程和Pitzer电解质理论为基础,能在很宽广温压范围内预测温度、压力、盐度和毛细管力对甲烷水合物形成和分解的影响。通过对比本模型的预测结果与实验数据,可知本模型能够准确地预测海水和多孔介质中甲烷水合物的相平衡条件。对于一定盐度下多孔介质中甲烷水合物的形成温压条件的在线计算可浏览: www.geochem model.org/models.htm。