巴林左旗-阿鲁科尔沁旗5.9级地震前地震活动异常特征

对2003年8月16日巴林左旗阿鲁科尔沁旗间5．9级地震前震源区附近地震活动图像和地震学参数研究结果表明，震前5～1年震源区附近地震活动异常平静，而外围(150km≤△≤300km)区地震活动显著增强；震前2年左右，震源区附近地震学参数异常比较明显，异常项数比40％；震前1．0～0．5年地震学参数异常明显减弱，异常项数比仅10％。可见，地震学短期异常不明显。     

Seasonal and Diurnal Variation of Surface Ozone and a Preliminary Analysis of Exceedance of its Critical Levels at a Semi-arid Site in India

The mixing ratios of surface O₃ were measured at St. John's College, Agra, an urban and traffic influenced area for the period of 2000–2002. The monthly averaged O₃ mixing ratios ranged between 8 to 40 ppb with an annual average of 21 ppb. Strong diurnal and seasonal variations in O₃ mixing ratios were observed throughout the year except for monsoon season. The mixing ratios of O₃ follow the surface temperature cycle and solar radiation (r = 0.72 and r = 0.65 with temperature and solar radiation, respectively). Concentrations were higher with winds associated with NE and NW direction indicating the impact of pollution sources on surface O₃ concentration. Exceedance of ozone critical level was calculated using the AOT 40 index and found to be 840 ppb.h and 2430 ppb.h for summer and winter seasons, respectively. The present O₃ exposures are lower than the critical level of O₃ and suggest that the present level of O₃ does not have any impact on reduction in crop yields.     

福建黄地金-多金属矿床地质特征

黄地金-多金属矿床严格受黄地逆冲推覆断层控制,矿脉(体)赋存于由推覆体构造带上下盘岩石所形成的碎裂岩化、糜棱岩化带中,并且金、铅、锌在空间上具有分段富集的特点.矿石为动力变质多金属硫化物蚀变岩型,主要有自形-半自形、他形粒状,包含、碎裂等结构,块状、浸染状、角砾状等构造.金属矿物主要有黄铁矿、磁黄铁矿、方铅矿、闪锌矿以及银金矿和自然金,非金属矿物主要为石英和绢云母.自然金主要产于黄铁矿的晶洞中,少部分包裹于非金属矿物中.成矿作用可分为岩浆接触交代期、气-水热液矿化期和氧化期,其中气-水热液矿化期的早期石英-硫化物阶段为主成矿阶段,成矿物质主要来源于动力变质作用所形成的深部矿化热液,为沿推覆构造充填交代所形成.     

中国南水北调工程进展综述

论述南水北调工程的调水背景、工程规划、工程特征、环境影响与生态环境保护及其工程综合效益。     

紫色土丘陵区典型小流域水体N、P含量及其环境特征

N、P各形态浓度在川中丘陵区小流域的水体中显示出明显的时空特征,在地表水中,以旱地为主的小流域上部的硝态氮、氨态氮、全氮要低于小流域下部水田的,而以流域人口密度较大的群英池和小流域下部的沟道水中氨态氮浓度较高,说明人为活动对其影响较大。在地下水中以小流域上部为最高,明显高于该流域的中下部;它们的季节变化与流域降水的季节变化基本是一致的。紫色土丘陵区水体富N,地下水NO_3~--N超标率达60％,;地表水和地下水均尚未出现P的富营养,但潜在的污染不可忽视。     

多年冻土地区建筑物地基的热稳定性技术

Thermal stabilization of soils (including freezing of thawed soils and cooling of permafrost) is known to be the effective method providing stable support for buildings and structures in cold regions.Seasonal thermo-stabilizers (STS) are mainly used in construction. The predicted climate warming because of natural and man-caused factors determines wide application of STS in permafrost regions. A STS transfers heat from its underground part (evaporator) to the aerial part (condenser) owing to natural temperature difference between them during a cold season. We have been working out and manufacturing different types of two-phase, vapor-liquid STS. Aluminum alloys are used in our STS to prevent corrosion and to increase their efficiency. They are successfully used in the northern regions of Western Siberia, in particular, at the railway Obskaya Bovanenkovo. The paper presents some technical parameters of new STS, the results of their experimental study and computer simulation, as well as experience features.     

Structural features and petroleum geology of the fold-thrust belt in the southern Tarim basin, China

The west Kunlun fold-thrust belt (WKFTB) and the Altun fold-thrust belt (AFTB) are respectively located in the southern margin of the Tarim basin, NW China. The analyses of typical structures and regional dynamics of the fold-thrust belts reveal their different structural and petroleum features and mechanisms. WKFTB differs from AFTB by abundant fault-related folds and triangles zones, and was formed by northward extrusion of the west Kunlun orogen. AFTB was affected synchronously by northward extrusion of the Altun orogen and the sinistral strike-slipping of the Altun Fault, so it is characterized by the minor scale and the monotonous structural styles. The Aqike anticline and the Aqike fault, of which the strikes are orthogonal to the strike of the fold-thrust belts, are regarded as the adjustive structures between both of the fold-thrust belts. The oil-gas pools of WKFTB develop mainly in the faulted-related anticline traps, but the oil-gas pools of AFTB develop mainly in the low fault-block and anticlines traps related with the paleo-uplifts. There are different exploration countermeasures for both of the fold-thrust belts.     

内蒙古巴彦塔拉盆地砂岩型铀矿化的蚀变特征

巴彦塔拉盆地砂岩型铀矿床产于下白垩统赛汉塔拉组下段辫状河流相砂岩中。本文通过对含矿主岩沉积特征、矿化和矿床蚀变特征的分析研究 ,认为早期为潜水氧化蚀变成矿 ;晚期为层间氧化 油气还原蚀变成矿 ,即来自蚀源区和天窗补给的含铀、含氧地下水遇沿断裂 (F2 1)上升的含H2 S的油气还原叠加改造成矿     

勃利盆地中生界地质特征与油气资源量计算

黑龙江省东部勃利盆地在早白垩世为陆缘断陷盆地。经晚白垩世和新近纪的构造反转改造后，呈改造残留型含油气、含煤盆地。该盆地在下白垩统发育有厚度较大的暗色泥岩和多套煤系地层。盆地内源岩有机质以生气为主，煤系地层为重要的气态烃的来源。在研究了勃利盆地中生界地质特征的基础上，运用蒙特卡罗法初步估算了盆地内的油气资源量，得出盆地油气资源量的概率分布函数图，取得不同概率下的油气资源量值。盆地的中部断陷为有利含油气区。研究结果为进一步在松辽盆地外围寻找油气资源提供了参考依据。     

濮阳市地热资源特征

本文根据钻探资料和近年的勘查研究成果,结合部分已开发利用地热资源情况,对濮阳市地热资源的分布特征、赋存规律和地热田的结构进行了初步分析。指出濮阳市地热资源的分布在平面上可分为3个区,即西区、中区和东区。西区平均地温梯度为3 5℃/100m,地下热水主要储存于奥陶系马家沟组灰岩溶洞溶隙中,温度>60℃,而30～60℃的温水和温热水储存于上第三系明化镇组砂岩裂隙孔隙之中,埋深300～1080m;中区和东区的地热资源主要储存于上第三系馆陶组和明化镇组砂岩裂隙孔隙之中,中区平均地温梯度为3 2℃/100m,东区平均地温梯度为2 8℃/100m,地下热水埋藏深度在中区和东区依次加深。文中还对濮阳市地热田的储、盖、通、源等主要条件及其形成特征进行了论述。