晋南平顺地区两岩浆岩带内在联系及找矿意义

平顺铁矿为山西省南部典型的矽卡岩型铁矿床之一,矿区内发育有东西两岩浆岩带,它们的化学性质相似,具有低硅(绝大部分小于56%)、高镁(Mg#=51.47～81.66,平均值为61.42);富集大离子亲石元素(如Sr、Ba、K)和亏损高场强元素(如Nb、Ta、Ti);LREE富集,HREE亏损,无或只有微弱的正铕异常,富集放射性成因Pb,以及第一岩浆岩带橄榄辉长岩含有大量橄榄石、角闪石和辉石的捕掳晶等特点,显示两岩浆岩带具有起源相同、快速侵位的特点。平顺地区6个典型钻孔岩性的化学分析结果说明岩浆后期热液具有从东往西运移的趋势。结合两岩浆岩带侵位特点,提出第二岩浆岩带是由第一岩浆岩带晚期岩浆侧向侵位形成,二者之间在某一范围内深部相连,并可能成矿的观点。这为本区将来深部找矿提供理论依据。     

浅议轻雾与霾的区别

本文从轻雾与霾的成因、颜色、出现时的天气条件以及指示意义等方面分析二者的区别,并探讨这两种天气现象的观测记录,以此抛砖引玉,制定一个统一的轻雾与霾的区分标准。     

桂北新元古代两类过铝花岗岩的地球化学研究

广西北部新元古代花岗岩类岩石包括黑云母花岗闪长岩和黑云母花岗岩。地球化学特征表明，黑云母花岗闪长岩与含堇青石的过铝花岗岩（CPG）相当，而黑云母花岗岩则类似于白云母二长花岗岩（MPG）。黑云母花岗岩类是成熟地宙岩石部分熔融作用的产物，而黑云母花岗闪长岩类的形成与地幔柱起源的镁铁质岩浆和地壳起源的过铝质黑云母花岗岩浆之间的混合作用有关。这两类新元古代过铝花岗岩的形成与碰撞造山导致地壳加厚的挤压性构造无关，而与导致Rodinia超大陆裂解的地幔柱上升诱发岩石圈伸展的张性构造相联系。     

Chronological and Geochemical Characterisitics of Volcanic Rocks of the Yingcheng Formation in the Southern Songliao Basin: Constraints on the Early Cretaceous Evolution of the Songliao Basin

The discoveries of oil and gas reservoirs in the volcanic rocks of the Songliao Basin(SB) have attracted the attention of many researchers. However, the lack of studies on the genesis of the volcanic rocks has led to different opinions being presented for the genesis of the SB. In order to solve this problem, this study selected the volcanic rocks of the Yingcheng Formation in the Southern Songliao Basin(SSB) as the research object, and determined the genesis and tectonic setting of the volcanic rocks by using LA-ICP-MS zircon U-Pb dating and a geochemical analysis method(major elements, trace elements, and Hf isotopes). The volcanic rocks of the Yingcheng Formation are mainly composed of rhyolites with minor dacites and pyroclastic rocks. Our new zircon U-Pb dating results show that these volcanic rocks were erupted in the Early Cretaceous(113–118 Ma). The primary zircons from the rhyolites have εHf(t) values of +4.70 to +12.46 and twostage model age(TDM2) of 876–374 Ma. The geochemical data presented in this study allow these rhyolites to be divided into I-type rhyolites and A-type rhyolites, both of which were formed by the partial melting of the crust. They have SiO2 contents of 71.62 wt.%–75.76 wt.% and Al2 O3 contentsof 10.88 wt.% to 12.92 wt.%. The rhyolites have distinctively higher REE contents than those of ordinary granites, with obvious negative Eu anomalies. The light to heavy REE fractionation is not obvious, and the LaN/YbN(average value = 9.78) is less than 10. The A-type rhyolites depleted in Ba, Sr, P, and Ti, with relatively low Nb/Ta, indicating that the rocks belong A2 subtype granites formed in an extensional environment. The adakitic dacites are characterized by high Sr contents(624 to 1,082 ppm), low Y contents(10.6 to 12.6 ppm), high Sr/Y and Sr/Yb ratios, and low Mg# values(14.77 to 36.46), indicating that they belong to "C" type adakites. The adakitic dacite with high Sr and low Yb were likely generated by partial melting of the lower crust under high pressure conditions at least 40 km depth. The I-type rhyolites with low Sr and high Yb, and the A-type rhyolites with very low Sr and high Yb, were formed in the middle and upper crust under low pressure conditions, respectively. In addition, the formation depths of the former were approximately 30 km, whereas those of the latter were less than 30 km. The geochemical characteristics reveal that the volcanic rocks of Yingcheng Formation were formed in an extensional environment which was related to the retreat of subducted Paleo-Pacific Plate. At the late Early Cretaceous Period, the upwelling of the asthenosphere mantle and the lithosphere delamination caused by the retreat of the subducted Paleo-Pacific Plate, had resulted in lithosheric extension in the eastern part of China. Subsequently, a large area of volcanic rocks had formed. The SB has also been confirmed to be a product of the tectonic stress field in that region.     

Comparative studies of Danxia landforms in China

Danxia geomorphology originates from China. This paper studies the spatial distribution and differences in characteristics of Danxia landforms. Based on relevant research and investigations, three congregated areas of Danxia landform in China are discussed in this paper. They are the southeast area (including Jiangxi, Fujian, Zhejiang, Hunan and Guangxi provinces), the southwest area (the transitional zone of Yunnan-Guizhou Plateau and Sichuan Basin) and the northwest area (including Longshan mountain and along the banks of the Huanghe River and its anabranches). Not only the conditions of geology and geography of the three areas but also the differences of Danxia landforms of the three areas are analyzed. The Danxia landscape, characterized by upright-shaped peaks, Danxia mesa, stone wall, cave and vertical cave, "Danxia natural bridge", "a narrow strip of sky" and so on, often presents in the southeast area. The landscape of southwest area is characterized by Danxia escarpment faces and waterfalls. In the northwest area, the Danxia landscape has the traits of arid areas simultaneously, for example, mud-coating type, columniation type, board type, moreover, it is greatly different between these environmental factors such as the microclimate, water, wind, and the loess cover. Finally it explores the causes which lead differences in landform and also explains the landform formation process and its mechanism with reference to the rates of crustal uplift, the tectonic red-basin, and the external processes including working of running water, weathering, biogenic, gravity in each area of Danxia Landforms in China.     

基于ESDA的区域经济空间差异分析——以江苏省为例

基于ESDA全局和局部空间自相关分析,利用江苏省1978～2002年县域人均GDP数据,对江苏省县域总体和局部空间差异的变化趋势、特征与成因进行了初步探索。结果首先表明,随着我国改革开放进程的逐步深化,江苏省县域经济空间差异在总体上呈现缩小趋势。其次,江苏省县域局部空间差异不断缩小,特别是苏南和苏北县域,表现出与周边地区同步发展态势。再者,苏南地区对全省的极化效应明显大于其扩散效应。大致自1992年以来,苏南和苏北地区内部分别形成了与周边地区显著相似的区域。最后,江苏省县域总体和局部空间差异的缩小并不是全省区域经济协调发展的标志,而是南北空间分异的表现。在循环累积因果机制作用下,南北差异有可能进一步扩大。     

遥感信息不确定性研究

近年来遥感技术及遥感信息产业化发展迅猛 ,但遥感信息的不确定性制约着遥感信息的产品化和实用化的进一步发展。虽然 ,这一问题得到了国内外众多学者的关注 ,并提出和采用相关理论和方法进行分析 ,取得了相当的进展 ,但这些方法在分析遥感信息不确定性时忽略了一个重要的研究点 :遥感信息的不确定性传递机理。本文主要目标就是建立一套遥感信息不确定性的处理方法     

安阳区域性夏季大旱成因分析

利用1957～1998年安阳区域夏季降水资料，确定安阳区域性夏季大旱的标准，分析了大旱成因：东亚沿海低槽较常年异常深厚和偏东以及西太平洋副高异常偏东、偏南和偏弱；当年6～8月太阳黑子相对平均数处于谷点或从谷点开始上升时期；当年春季出现厄尔尼诺或存在厄尔尼诺现象，绝大部分安阳降水偏少或特少，出现干旱或大旱；6～8月西风急流轴异常偏北，也是造成安阳区域性夏季大旱的原因之一。     

用于不规则界面多层介质的地震波方法比较研究：不规则地形问题

通过研究SH波入射时各种地形的散射，从计算结果的精确性、稳定性和计算效率三个方面研究Aki Larner方法、Bouchon Campillo方法、以及全局广义反-透射矩阵方法（Chen's方法），比较这三种计算具有不规则界面多层介质中理论地震图的离散波数方法. 由于利用了FFT算法，Aki Larner方法速度最快，但由于方法本身受到Rayleigh假设的限制，结果精度最差. Bouchon Campillo方法非常稳定，结果较精确；但其计算效率最低，并且不能正确地处理非常陡峭的地形问题. 全局广义反-透射矩阵方法非常稳定，结果最精确，能够很好地处理非常陡峭的地形问题，并具有适中的计算效率；因此是三种方法中的最佳方法，为计算复杂介质中的地震波动问题提供了十分有效的工具.     

安徽合肥遥测地震台网数字资料与模拟资料的综合对比

在安徽省数字观测系统将逐步取代模拟观测系统的过渡时期，对安徽霍山地区3个台站老皇寺、豹子崖、石家河进行了震级更正，对记录到的数字观测资料和模拟观测资料分别进行了对比。结果表明，经过A／D后的数字记录震级目前可以和其他数字台一起参与震级平均，数字记录结果和安徽省地震局编目结果偏差基本上未超过允许范围，速度震级和仿真位移震级之间的偏差在0．2以内。