肃北钻井沟金矿的矿石特征和金的赋存状态探讨

钻井沟金矿主要的矿石类型为含金多金属硫化物石英脉和含金白云母石英岩,矿石结构以粒状晶结构、碎裂结构和包含结构为主;构造主要为块状构造和浸染状构造。金矿物为自然金,以裂隙金为主,少量包裹金,金矿物以中粗粒金为主,载金矿物为黄铁矿、黄铜矿和石英。矿石中金的品位高,赋存状态简单,有害元素砷、锑、硫、碳等的含量低,属易浸型矿石。采用浮选—氰化联合工艺流程,金的综合回收率可以到达99.24%。     

陕北延安地区基底断裂及其油气地质意义

以重磁力资料为基础,结合钻井及地质地震资料,推测出研究区有8条基底断裂。已有油田大都沿基底断裂走向分布在断裂两侧,勘探井的试气产量高低与基底断裂分布关系密切,基底断裂的"隐性"活动导致沉积盖层中发育构造裂缝且以垂直裂缝为主,裂缝不仅能作为油气运移的通道,而且能提高储层的孔隙度和渗透率,对研究区内油气分布及储层产能起关键作用。     

Localization of temperature anomalies in the Upper Rhine Graben: insights from geophysics and neotectonic activity

The European Cenozoic Rift System hosts major temperature anomalies in Central Europe. In its central segment, the Upper Rhine Graben (URG), temperatures range from 75°C to nearly 150°C at a depth of 2000 m. Different hypotheses have been suggested to explain the localization of these anomalies. Our review and comprehensive interpretation of gravimetric and magnetic data, as well as neotectonic activity patterns, suggests that low-density, mostly magnetic and fractured granitic basement is systematically associated with major temperature anomalies. Further analyses provide insight into different heat transport processes contributing to the localization of these anomalies. Magnetic and gravity anomalies are known to represent lithological variations associated with the pre-Permian. We show their spatial relationship with positive temperature anomalies in the URG. Correlation between magnetics and temperature reveal a mean contribution of heat production to the temperature anomaly of about 10–15°C. A slightly higher mean value is obtained from correlation between gravity and temperature, which may be attributed to effects resulting from fracture porosity. The spatial relationship between temperature anomalies and neotectonic patterns indicates compressional shear and uplift regime for the major anomalies of the central segment of the URG. This is in agreement with different numerical models indicating free convection on fracture zones linked to faults. Our findings show that about 15–25% of the temperature anomaly can be attributed to variation in heat production. Hydrothermal circulation convection along faults, activated by the tectonic context, may explain the remaining 75–85% of the temperature anomalies.     

Objective Identification and Climatic Characteristics of Heavy-Precipitation Northeastern China Cold Vortexes

The northeastern China cold vortex(NCCV) plays an important role in regional rainstorms over East Asia. Using the National Centers for Environmental Prediction Final reanalysis dataset and the Global Precipitation Measurement product,an objective algorithm for identifying heavy-precipitation NCCV(HPCV) events was designed, and the climatological features of 164 HPCV events from 2001 to 2019 were investigated. The number of HPCV events showed an upward linear trend, with the highest frequency of ...     

阿勒泰夏季大降水过程中高潜能场的时空变化特征分析

以大降水过程中触发高潜能量释放的天气系统为背景条件，以高潜能场为起报信息，对40个大降水个例进行统计、分析和归纳，概括出阿勒泰夏季大降水过程中，高潜能场的时空变化特征，从中得出预报阿勒泰夏季大降水的新指标，进一步提高了大降水预报的准确率。     

STRUCTURE FEATURES AND COMPOSITE ANALYSIS OF CONVECTIVE CELLS IN A WARM SECTOR HEAVY RAINFALL EVENT OVER SOUTHERN CHINA

This paper uses the ARW-WRF model to carry out a numerical simulation of a warm-sector heavy rainfall event over southern China on the 22–23 May, 2014. A composite analysis method was used to analyze the evolution process and structural features of the convective cells on a convection line during this rainfall event. This analysis identified three stages: (1) Stage of activation: the equivalent potential temperature surfaces as lower layers start to bulge and form warm cells and weak vertical convective cloud towers which are subject to the impact of low-level warm moist updrafts in the rainfall sector; (2) Stage of development: the warm cells continue to bulge and form warm air columns and the convective cloud towers develop upwards becoming stronger as they rise; (3) Stage of maturity: the warm air columns start to connect with the stable layer in the upper air; the convective cloud tower will bend and tilt westward with each increasing in height, and the convection cell is characterized by a “crescent-shaped echo” above the 700hPa plane. During this stage the internal temperature of the cell is higher than the ambient temperature and the dynamic structural field is manifested as intensive vertical upward movement. The large-value centers of the northerly and westerly winds in the middle layer correspond to the warm moist center in the cells and the relatively cold center south of the warm air column. Further analysis shows that the formation of the “crescent-shaped” convective cell is associated with horizontal vorticity. Horizontal vorticity in the center and west of the warm cell experiences stronger cyclonic and anticyclonic shear transformation over time; this not only causes the original suborbicular cell echo shape to develop into a crescent-like shape, but also makes a convection line consisting of cells that develop to the northwest.     

青藏高原近50年来气温的年代际变化

根据青藏高原及周边地区一百多个气象台站的月平均气温资料,利用统计方法,分析了近50年来气温的年代际变化。结果表明：整个高原地区温度变化可分为6个不同的区域。在时间演变上可划分出相对高温时段(1963年以前)、相对低温时段(1963—1987年)和另一个相对高温时段(1987年以后)。还从天文因素、地球系统各圈层及气候系统内各因子相互作用和相互制约出发,探讨了引起高原气候变化的可能原因。     

Kinematic features of a bow echo in southern China observed with doppler radar

A bow echo is a type of mesoscale convective phenomenon that often induces extreme weather and appears with strong reflectivity on radar images. A strong bow echo that developed from a supercell was observed over Foshan City in southern China on 17 April 2011. The intense gusty winds and showers caused huge losses of property and severely affected human lives. This paper presents an analysis of this strong meso- n-scale convective system based on Doppler radar observations. The isolated bow echo exhibited a horizontal scale of about 80 km in terms of reflectivity above 40 dBZ, and a life span of 8 hours. The system originated from the merging of a couple of weakly organized cells in a shear line, and developed into an arch shape as it moved through the shear zone. Sufficient surface moisture supply ensured the convective instability and development of the bow echo. The low-altitude winds retrieved from single Doppler radar observations showed an obvious rear-inflow jet along the notch area. Different from the conventional definition, no book- end anticyclone was observed throughout the life cycle. Very strong slantwise updrafts and downdrafts were recognizable from the retrieved winds, even though the spatial scale of the bow echo was small. Strong winds and induced damage on the surface are considered to have been caused by the mid-level rear-inflow jet and intense convective downdrafts.     

共轭面状特征的快速提取与遥感影像精确配准

使用数学形态学的"膨胀算子"对影像进行预处理,提出了一种改进的基于高斯拉普拉斯算子的面状特征提取和细化方法,并利用边界代数快速标注边界封闭的面状特征。在提取面状特征的基础上,利用奇异值分解算法,实现了基于面状质心的遥感影像匹配,进而完成精确配准。实验结果表明,与传统方法相比,此方法在速度与准确度上具有明显优势。