珠江三角洲地区重磁资料解释的深部断裂及其新构造意义

对珠江三角洲地区布格重力和航磁资料系统处理、研究、解释,确认珠江三角洲地区地壳深部存在近EW向、NW向和NE向3组断裂系统。近EW向断裂是深部主要断裂系统,大部分断裂深及30km以上,其中有些断裂是以往很少为人们关注的; NW向断裂分布也比较广泛,但深度相对较浅,大都在10km左右,不超过20km; NE向断裂虽然地表出露最广,规模最大,但只有广州－恩平断裂可深及30km 以上,大多数也相对较浅,特别是以往一些被称为深大断裂的断裂只有10km左右深度,不超过20km。上述工作新成果同传统概念的珠江三角洲地区深大断裂格局有较大改变。本文提出“新构造期深大断裂”的新概念及理论分析、解释这种格局的改变。并认为它对研究新构造、地质构造、工程地质、地震地质、找矿、找水、地质灾害等方面或具有科学理论意义和实用价值。文章还阐述了近EW,NW和NE向3组断裂间的相互切割关系,认为前二组断裂活动较NE向断裂更活跃或更新一些。     

江苏地区大气降尘元素地球化学特征与城市地质调查有关问题研究

通过对江苏南京市等典型地区大气降尘样品微量元素分布数据的分析研究,总结了上述各地大气降尘的元素含量分布等地球化学特征,发现不同地区大气降伞的微量元素分布存在明显差异,Cd、Ph、Zn、Se、S等元素在大气降尘中呈相对寓集趋势,城市地区大气降尘污染程度总体要高于乡村,部分降尘样品中Cd、Pb、Zn、Cr、Nj等重金属元素的超量富集与人为活动有关.认为大气降尘环境地球化学调查可在城市土地资源规划利用与保护、产业合理布局、地表物质循环研究、居民健康等方面发挥独特作用,建议今后江苏城市地质调查工作增加这方面的研究内容.     

The influence of biodegradation on resins and asphaltenes in the Liaohe Basin

Asphaltenes are traditionally considered to be recalcitrant to microbial alteration. Resins and asphaltenes of seven biodegraded oils extracted from reservoir cores of two columns (Es3 and Es1) of the Lengdong oilfield in the Liaohe Basin, NE China, were studied to test this hypothesis. Elemental (C, H, N, O, S) and isotopic compositions (δ¹³C and δ¹⁵N) were measured, FT-IR was used to study the oxygenated functionalities of both resins and asphaltenes, and Py–GC–MS was used to elucidate how alkyl side chains of asphaltenes were altered during biodegradation. We conclude that the products of biodegradation, such as carboxylic acids, phenol and alcohols, may not only contribute to the resin fraction of crude oils, but also are linked with functionalities of resins and asphaltenes. The amount of asphaltenes increases because some resin molecules are enlarged and their polarity increased such that they can be precipitated by hexane as newly generated asphaltenes. Thus, the hydrocarbons that are progressively consumed during biodegradation can pull the δ¹³C of asphaltene fraction closer to the δ¹³C of the altered resins and hydrocarbons that were consumed.     

宽频地震计及倾斜、重力仪对长周期波动信号的综合观测

报道了在武汉华中科技大学地震与固体潮试验站的同一观测平台上,用数字宽频地震计、倾斜仪及重力仪对长周期地震波动信号的综合观测结果,以及各观测的对比和分析。近3年来,不同的观测仪器同时观测到了几十个形态一致、信号较弱而且成分复杂、持续时间大多约为2——3天的异常波（震颤）。分析表明,这些异常震颤中的一部分由来自西太平洋进入中国大陆及近海的台风产生,其信号强弱主要与台风运动中心进入中国大陆近海后与观测点之间的距离,以及风速大小这两个因素密切关联。另外,还有一部分异常震颤信号的产生原因不明。频谱分析结果显示,与平常的背景噪声信号相比,异常震颤信号的成分较为丰富, 除了3——5 min周期的信号外,还含有20——30 min,甚至一小时以上的长周期信号。我们以多种观测仪、长时间的连续观测结果表明,这种震颤信号是真实的和普遍存在的。其产生原因和机制还有待更广泛和深入的研究。      

人工边界高频振荡失稳机理的一点注记

进一步完善了人工边界高频振荡失稳机理的解释. 解析证明了对于一维波动模型的离散模型, 当人工波速大于1.5倍的离散空间步距与时间步距的比值时, 则在某一高频段内, 其稳态波动解在人工边界上反射系数的模大于1的命题. 在此基础上对失稳的高频段作了进一步的讨论, 揭示了高频振荡失稳发生于对波动数值模拟无意义的高频段.      

Preliminary Study on the Dynamic Variations of the Surface Thermal Flux before and after the M_S5.7 Earthquake of 2005 in Jiujiang City,Jiangxi Province

The temporal and spatial variations of surface latent heat flux （SLHF） and diagnostic air temperature at 2m before and after the Ms5.7 earthquake occurring on November 26, 2005 in the area between Ruichang City and Jiujiang City, Jiangxi Province are summarized in this paper. It is found that before the earthquake significant SLHF anomalies and air temperature anomalies occurred in the epicentral area and its vicinity. The air temperature anomalies appeared from the 2nd to the 13th of November, 2005 and were concentrated at the epicentral area and in its southern part. Then two days later, that is, from the 4th to the 15th of November 2005, significant SLHF anomalies occurred in the epicentral area and to its northern area where many lakes are distributed along the active faults. During the anomalous period, the SLHF and air temperature at 2m exceeded the sum of average daily value over 26 years and 1.5 times of its mean square deviation. Both anomalies had maintained for 12 days with a peculiar distribution related to the tectonic active zone. It is considered that both of air temperature anomalies and SLHF anomalies are correlated to the movement of thermal flux from underground prior to earthquake. SLHF anomalies occurred over wide regions covered with abundant water, whereas air temperature anomalies occurred over land.     

塔里木盆地志留系下砂岩段成藏组合分析及有利勘探区带评价

多年勘探实践证明,塔里木盆地志留系发育良好的储盖组合,油气源充足,具有良好的勘探前景。以油气成藏组合理论为指导,结合塔里木盆地志留系勘探实践,将志留系下砂岩段划分为塔中、塔东、塔河地区3个油气成藏组合,并引入边缘概率对各成藏组合内的次级成藏组合进行综合分析。塔中地区储盖条件、圈闭条件发育良好,各次级成藏组合边缘概率均很高,综合评价为Ⅰ-Ⅱ类有利勘探区;塔东地区、塔河地区圈闭条件发育良好,但储盖条件不理想,各次级成藏组合边缘概率较低,综合评价为Ⅱ-Ⅲ类有利勘探区。     

Deep Tectonic Processes and Superaccumulation of Metals Related to Granitoids in the Nanling Metallogenic Province, China

The Nanling region is an important nonferrous and rare metal metallogenic province in South China, in which most of the deposits are related to granitoids in genesis. It covers southern Hunan, southern Jiangxi, Guangxi, Guangdong and Fujian provinces, with a total area of about 550,000 km2. This metallogenic province is well known in the world for its rich tungsten and tin resources. In the past 40-odd years, a vast amount of mineral exploration activities and studies of the geology of mineral deposits have been carried out and great achievements obtained in the province. This paper is focused on a discussion about the deep tectonic processes in the orogenic belt during the Mesozoic and their contribution to the superaccumulation of metals. Tectonically, this metallogenic province is composed of three units: (1) the marginal continental orogenic belt in the Southeastern Coast fold system in the Yanshanian; (2) the intercontinental orogenic belt in the collision suture belt between the Yangtze and Cathaysian plates mainly in the Caledonian; and (3) the intracontinental orogenic belt induced by subduction of the ocean crust and delimination of the mantle lithosphere in the Yanshanian. It is suggested that superaccumulation of metals in this metallogenic province was caused by the existence of mantle rooted tectonics at the depth based on comprehensive studies of geophysical information of seismic, geothermal and magnetotelluric surveys in Nanling and its adjacent areas. The Xihuashan wolframite quartz vein deposit, the Shizhuyuan W, Sn, Mo, Bi greisen-skarn deposit and the Dachang tin-polymetallic deposit are three typical examples of the deep tectonic processes. However, this kind of deep tectonic processes only act as the "engine" of the superaccumulation of metals, which means that they should have to correspond with the super-crust ore-controlling pattern of "lines-rows-clusters" (L-R-C). This recognization is expected to play an important role in assessment of mineral resources in this province.     

Deep Tectonic Processes and Superaccumulation of Metals Related to Granitoids in the Nanling MetaUogenic Province,China

The Nanling region is an important nonferrous and rare metal metallogenic province in South China, in which most of the deposits are related to granitoids in genesis. It covers southern Hunan, southern Jiangxi, Guangxi, Guangdong and Fujian provinces, with a total area of about 550,000 km2. This metallogenic province is well known in the world for its rich tungsten and tin resources. In the past 40-odd years, a vast amount of mineral exploration activities and studies of the geology of mineral deposits have been carried out and great achievements obtained in the province. This paper is focused on a discussion about the deep tectonic processes in the orogenic belt during the Mesozoic and their contribution to the superaccumulation of metals. Tectonically, this metallogenic province is composed of three units: (1) the marginal continental orogenic belt in the Southeastern Coast fold system in the Yanshanian; (2) the intercontinental orogenic belt in the collision suture belt between the Yangtze and Cathay     

江西中部青白口纪晚期潭头上升雏议

青白口纪神山组与库里组之间有沉积间断,存在岩相、沉积环境突变界面,两者为平行不整合接触关系,对这一地壳上升运动,命名为潭头上升。