甘肃北山南金山—狼娃山金成矿带成矿作用特征   总被引：1，自引：0，他引：1  

刘东晓  董雅清  张月宝 《甘肃地质》2009,18(4):29-33

通过对南金山—狼娃山金成矿带金矿床成矿地质背景、矿床特征、成矿标志及控矿因素等诸方面分析认为,该成矿带金成矿作用集中在海西中晚期,具明显的区域性成矿特征,金矿集中分布在下石炭统扫子山组、白山组火山岩和海西期中酸性（石英闪长岩、花岗闪长岩）侵入岩体内外接触带中。金成矿受含矿建造、岩浆活动和构造控制,据其成矿和分布特点划分了矿床预测类型（矿床式）,建立了区域找矿模型。  相似文献   

甘肃省东南部花岗岩区铀矿找矿远景预测          下载免费PDF全文

张甲升 《甘肃地质》2009,(2):48-52

本文对甘肃省东南部花岗岩区铀矿成矿远景进行了初步探讨。在对区内铀矿地质资料分析研究的基础上,提出了花岗岩分布区铀矿找矿远景区和有远景的铀矿化类型。  相似文献   

汶川地震甘肃省重灾区次生地质灾害及防治          下载免费PDF全文

赵成 《甘肃地质》2009,(2):53-57,97,99

本文根据“5．12”汶川地震地质灾害应急排查资料,认为甘肃重灾区次生地质灾害的类型主要为崩塌、滑坡和泥石流,分析了其分布规律和成因,对典型地质灾害进行了解剖,阐述了近期地质灾害防治的重点,为灾后重建及该区地质灾害防治提供参考依据。  相似文献   

甘肃古浪地区石炭系羊虎沟组层内褶皱特征及其对煤层的控制作用     

余君鹏  李增 《甘肃地质》2009,(1):47-50

本文探讨的是见于甘肃古浪地区石炭系羊虎沟组含煤建造中普遍发育的层间褶皱特征、形成机制及其对煤层储聚的控制作用,研究发现石炭纪地层中的层内褶皱具有多方位的褶皱枢纽,具非共轴叠加褶皱形态,经历了早期B形和晚期A形褶皱演化过程,最终形成AB复合型褶皱,此类褶皱普遍控制了该套岩层中煤层的储聚。本文在分析了该类褶皱的几何形态特征及其变形控制条件的基础上,探讨了它的形成演化机制和控煤特征。  相似文献   

煤田三维和二维地震勘探相结合的应用——以窑街矿区为例   总被引：1，自引：0，他引：1       下载免费PDF全文

张玉军 《甘肃地质》2009,(1):82-86

针对勘探区复杂的地震地质条件,通过运用三维和二维地震勘探相结合的施工方案,采取合理的观测系统,选取有效的激发与接收因素等技术措施,依照设计精心组织野外施工,做好资料处理与解释,取得了较好的地质效果。实践证明这是一种有效的方法。  相似文献   

甘肃阳山超大型金矿成因研究评述   总被引：4，自引：0，他引：4  

赵成海 《矿物岩石地球化学通报》2009,28(3):286-293

阳山金矿床位于西秦岭勉略缝合带内,是我国近期发现的世界级超大型金矿床.本文根据前人稳定同位素和流体包裹体地球化学以及年代学研究,结合矿区构造地质背景和矿物组合,讨论其成因机制.研究表明, 阳山金矿床的形成时间与勉略缝合带碰撞期(晚三叠世-早侏罗世)的构造-岩浆事件接近.碰撞造山作用是大规模花岗岩浆活动的主要诱因.大量变质流体在岩浆热驱动下,沿花岗斑岩与破碎千枚岩的接触带上涌,萃取地层中已相对富集的金,并以络合物的形式搬运成矿.阳山超大型金矿床兼有卡林型金矿和造山型金矿的特征,又有与两者明显区别的地质和地球化学特征,在西秦岭地区的金矿床中具有重要的代表性.  相似文献   

IMPACTS OF ATOVS DATA ASSIMILATION ON PREDICTION OF A RAINSTORM OVER SOUTHEAST CHINA   总被引：1，自引：1，他引：0  

万齐林  徐建军  何金海 《热带气象学报(英文版)》2009,15(2):155-161

Using the Advanced Research WRF (ARW WRF) model and the Gridpoint Statistical Interpolation (GSI) three-dimensional variational analysis (3DVAR) system, the impact of assimilating ATOVS (Advanced TIROS Operational Vertical Sounder) radiance through the prototype Community Radiative Transfer Model (pCRTM) is evaluated on the forecasting of a heavy rainstorm occurring over the central Guangdong province in the southeast of China on 20-21 June 2005. A pair of comparison experiments (NODA and DA) for this case is conducted with multiple configurations, including nesting domains with 4-km and 12-km grid distances. The results showed that by changing the initial condition through data assimilation, a modified divergence and moisture field with the structure of dipoles has been added to the axis of the rainband with a southwest-northeast orientation. When more moisture carried by a southwesterly low level jet (LLJ) was converged into the northeast portion of the rainband around the observatory station of Longmen, the amplitude of moisture static energy (MSE) increased substantially at low levels much more than at middle levels, resulting in the enlarging of differences in MSE between 500 hPa and 850 hPa; the atmosphere became more unstable. Consequently, the convective rainfall increased in the northeast part of the province around the Longmen station, which was consistent with the observed distribution of rainfall.  相似文献   

白银大型金属矿山环境地质问题及防治   总被引：5，自引：0，他引：5  

汤中立  李小虎 《国土资源》2005,(8):4-7

白银市位于甘肃中部,是我国重要的以铜资源为主的资源型城市,也是上世纪50年代国家重点建设的老工业基地之一,经过50多年的开发建设,白银市已成为国家有色金属工业基地,甘肃的能源、化工基地.然而,矿业开发在为甘肃省乃至国家经济发展做出巨大贡献的同时,也诱发了严重的矿山环境地质问题,在矿产资源的采、选、冶等过程中所产生的废气、废水、废渣、对矿山及周围的水、土、气及植被造成了严重的污染甚至破坏。  相似文献   

AN ANALYSIS OF THE WINTER EXTREME PRECIPITATION EVENTS ON THE BACKGROUND OF CLIMATE WARMING IN SOUTHERN CHINA   总被引：2，自引：1，他引：1  

智协飞  张玲  潘嘉璐 《热带气象学报(英文版)》2010,16(4):325-332

Based on daily precipitation and monthly temperature data in southern China, the winter extreme precipitation changes in southern China have been investigated by using the Mann-Kendall test and the return values of Generalized Pareto Distribution. The results show that a winter climate catastrophe in southern China occurred around 1991, and the intensity of winter extreme precipitation was strengthened after climate warming. The anomalous circulation characteristics before and after the climate warming was further analyzed by using the U.S. National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis data. It is found that the tropical winter monsoon over East Asia is negatively correlated with the precipitation in southeastern China. After climate warming the meridionality of the circulations in middle and high latitudes increases, which is favorable for the southward movement of the cold air from the north. In addition, the increase of the temperature over southern China may lead to the decrease of the differential heating between the continent and the ocean. Consequently, the tropical winter monsoon over East Asia is weakened, which is favorable for the transport of the warm and humid air to southeastern China and the formation of the anomalous convergence of the moisture flux, resulting in large precipitation over southeastern China. As a result, the interaction between the anomalous circulations in the middle and high latitudes and lower latitudes after the climate warming plays a major role in the increase of the winter precipitation intensity over southeastern China.  相似文献   

Impacts of upper tropospheric cooling upon the late spring drought in East Asia simulated by a regional climate model   总被引：4，自引：0，他引：4  

辛晓歌  宇如聪  周天军 《大气科学进展》2008,25(4):555-562

Responses of late spring （21 April 20 May） rainfall to the upper tropospheric cooling over East Asia are investigated with a regional climate model based on Laboratoire de M6t6orologie Dynamique Zoom （LMDZ4-RCM）. A control experiment is performed with two runs driven by the mean ERA-40 data during 1958-1977 and 1981 2000, respectively. The model reproduces the major decadal-scale circulation changes in late spring over East Asia, including a cooling in the upper troposphere and an anomalous meridional cell. Accordingly, the precipitation decrease is also captured in the southeast of the upper-level cooling region. To quantify the role of the upper-level cooling in the drought mechanism, a sensitivity experiment is further conducted with the cooling imposed in the upper troposphere. It is demonstrated that the upper-level cooling can generate the anomalous meridional cell and consequently the drought to the southeast of the cooling center. Therefore, upper tropospheric cooling should have played a dominant role in the observed late spring drought over Southeast China in recent decades.  相似文献