Relationship model for the drilling parameters from a digital drilling rig versus the rock mechanical parameters and its application

Measuring rock mechanical parameters is an essential step for support design in an underground project. To quickly obtain the surrounding rock mechanical parameters at a construction site in real time using a digital drilling rig, a quantitative relationship between the drilling parameters and rock mechanical parameters should be defined. In this paper, based on the fracture characteristics of rock cutting, a relationship model for the drilling parameters of the digital drilling rig versus the rock mechanical parameters (DP-RMP model) is created. Based on the multi-function rock drilling test system developed by the authors, rock drilling tests for different drilling parameters and theoretical results are compared and analysed to prove the validity and accuracy of the DP-RMP model. Additionally, the influence laws of the cohesion and internal friction angle on the rock cutting drilling torque are investigated. Drilling parameters from the digital drilling rig-based rock mechanical parameter inversion method is proposed; the feasibility of this method is verified by rock drilling test results. The study provides a theoretical basis for quickly obtaining the rock mechanical parameters using drilling parameters on site in real time.     

Research on Rare Cranes Population Response to Land Use Change of Nature Wetland

Shengjin Lake is the only national wetland nature reserve in Anhui Province with rare wintering waterbirds as the main protection object. In recent years, with the strengthening of human activities, the number of rare cranes has changed significantly. Taking the Shengjin Lake natural wetland as an example, this paper studied the response of crane population to land use change, which had important implications for the protection of cranes. This paper analyzed the land use of Shengjin Lake by referring to the eight periods of TM remote sensing images (1986, 1990, 1995, 2000, 2004, 2008, 2011 and 2015) and using ERDAS and ArcGIS tools. The diversity of bird habitats in Shengjin Lake nature reserve was analyzed. Combined with the changes in the number of rare cranes from 1986 to 2015, the impacts of land use and climate change on the cranes in protected areas were analyzed. The results showed that: there was a correlation between the number of cranes land use types and climate changes. The type of land of Shengjin Lake nature reserve was relatively small change in the early years in 1986. It was a relatively large change in the type of land, and the number of cranes had a significantly reducing in 1990s. It until 2000, the number of rare cranes had a slight rebound; however from 2012 to 2015, the number of cranes had dropped again. It had a greater influence on the number of cranes about the change of construction land, reeds mudflats, mudflats, marsh land and paddy fields in the wetland.     

Ancient landslide in Wanzhou District analysis from 2015 to 2018 based on ALOS-2 data by QPS-InSAR

Natural Hazards - Landslide is a global environmental geological hazard caused by natural or human activities. Since the impoundment of the Three Gorges reservoir area, the geological disasters...     

黑龙江六九铜矿区岩浆岩年代学及成矿指示意义

六九铜矿床位于黑龙江省大兴安岭成矿带中段,龙江铜、金、钼成矿亚带.为了探讨矿床的形成时代和研究该地区岩浆活动,本次对侵入矿体的英云闪长斑岩采用电感耦合等离子体质谱仪LA-ICP-MS锆石U-Pb定年,结果为122.96±0.93 Ma,由此可限定成矿时代上限,结合区域铜成矿规律,推测六九铜矿的成矿时代为晚侏罗世—早白垩世,成矿背景是蒙古—鄂霍茨克洋俯冲闭合有关的造山—造山后环境.对区内出露的绢英岩进行锆石U-Pb定年,结果为303.7±1.6 Ma,代表其原岩花岗闪长岩的结晶年代为晚石炭世晚期,结合区域地质调查成果,表明研究区自华力西晚期以来存在多期次岩浆活动.     

珠江口外陆架海域表层沉积物重金属潜在生态风险评价及来源分析

基于2017年11月珠江口外陆架海域表层沉积物中Hg、As、Cu、Pb、Cd、Zn、Cr等7种重金属元素的调查结果,应用单因子标准指数和地累积指数法评价了研究海域表层沉积物环境质量,采用H?kanson潜在生态风险指数评价法定量评估沉积物中重金属的潜在生态风险,并利用Pearson相关性分析和主成分分析初步探究了研究海域沉积物中重金属的主要来源。结果表明:研究海域表层沉积物中7种重金属污染物含量均达到海洋沉积物质量一类标准,地累积指数显示研究海域表层沉积物环境整体处于清洁状态,部分站位中的As和Cd属轻度污染。总体来说,研究海域沉积物环境属于低潜在生态风险(综合潜在生态风险系数RI 150)。单项因子潜在生态风险由高到低为Cd Hg As Pb Cu Cr Zn,研究海域西部表层沉积物重金属Cd的潜在生态风险系数均值达到中等潜在生态风险水平。Cr、Cu和Zn元素具有相近来源,主要为工业产生的陆源污染物; Pb、As和Cd元素来源相似,来源于陆源工业和农业污染经大气沉降及海上交通污染;而Hg与其他重金属元素无明显相关。     

Temperature, Relative Humidity, and Cloud Fraction Predicted by the NCEP Global Forecast System at the ARM SGP Site during 2001-2008:Comparison with ARM Observations

利用美国大气辐射测量项目(ARM)制作的“气候模拟最佳估计”(CMBE)观测数据集,检验美国环境预报中心(NCEP)全球预报系统(GFS)2001～2008年在ARM Southern Great Plains(SGP)站点预报的大气温度、相对湿度和云量的垂直分布,主要结论如下:(1)NCEP GFS较好地预报出了温度和相对湿度的季节变化.就各个季节平均而言,NCEP GFS高估了1.5～12km的大气温度,同时低估了春冬季13～16km和秋冬季1.5km以下的大气温度,各高度上温度偏差绝对值小于1℃;NCEP GFS预报结果再现了观测到的相对湿度垂直分布的双峰结构,但是高估了4～12 km的相对湿度.模式分辨率提高(T170L42更新为T254L64)显著改进了14～18 km相对湿度的预报.(2)预报的云量在10 km以下小于观测值,在10～13 km则高于观测值,而且,NCEPGFS没有预报出非降水性低云的云量,其预报的降水云的云量在8km以下也低于观测值,反映出NCEP GFS模式中浅对流和深对流活动不够活跃.(3)NCEP GFS模式用预报的相对湿度和云水/云冰混合比(qc)诊断云量,采用同样的诊断公式由观测的相对湿度和NCEP GFS预报输出的qc计算云量,得到的云量在11 km以下所有高度上都更加显著地小于观测值,即比NCEP GFS对云量的低估更加严重,说明NCEP GFS可能低估了此高度区间的qc.(4)2001～2008年间NCEP GFS预报的温度、湿度和云量改进不显著,其预报云量和qc的误差很可能与模式中深对流和浅对流方案、层云微物理方案的不确定性有关.     

极端天气和气候事件的变化

自1950年以来的观测证据表明,有些极端天气和气候事件已经发生了变化。全球尺度上,人为影响可能已经导致极端日最低和最高温度升高;由于平均海平面上升,人类活动可能已对沿海极端高水位事件的增加产生了影响;具有中等信度的是,人为影响已导致全球强降水增加;由于热带气旋历史记录的不确定性、缺乏对热带气旋与气候变化之间关联的物理机制的完整认识及热带气旋自然变率的程度,将可检测到的热带气旋活动变化归因于人为影响仅具有低信度。将单一的极端事件变化归因于人为气候变化具有挑战性。对极端事件变化预估的信度取决于事件的类型、区域和季节、观测资料的数量和质量、基本物理过程的认知水平及模式对其模拟的可靠性。     

超强台风作用下钱塘江河口的台风浪计算

基于SWAN波浪传播模型建立包含风暴潮与天文潮耦合传播的台风浪数值模型,将1949年以来登陆我国大陆沿海最强的5612#台风作为典型的超强台风,计算了超强台风沿中线和北线路径登陆遭遇天文潮高潮位时产生的沿海波高过程。结果显示:河口波高总体分布下游大于上游,北岸大于南岸,两岸代表断面堤前最大有效波高可达5.5 m;中线路径生成的近岸台风浪波高为单峰过程,北线路径时北岸的波高出现双峰过程,波高峰值与风暴高潮位并非总是同步出现,两者时间差最大为4 h;根据频率曲线分析,中线、北线路径超强台风作用下乍浦站台风浪的重现期分别为135 a和350 a;中潮时的近岸台风浪波高比大潮降低0.1~0.2 m,小潮时再比中潮降低同样幅度。这些结论对海堤工程设计和防灾减灾具有重要意义。     

The Relationship between the Aleutian Low and the Australian Summer Monsoon at Interannual Time Scales

The relationship between the boreal winter(December,January,February) Aleutian Low(AL) and the simultaneous Australian summer monsoon(ASM) is explored in this study.A significant correlation is found between the North Pacific index(NPI) and ASM index,the bulk of which is attributed to the significant correlation after late 1970s.Significant differences in precipitation and outgoing long-wave radiation between typical negative and positive NPI years appear over the ASM area.A regression analysis of the circu...