云南禄劝县皎西乡土壤氡测量在易门-罗茨隐伏断裂研究中的应用

易门-罗茨断裂带是多期活动的大规模断裂带,以易门-罗茨断裂为主断裂。在禄劝县皎西一带,断裂带控制了南北向的串珠状第四系盆地,盆地内第四纪沉积物厚数米至数十米,主要的控盆隐伏断裂位置、特征难以确定。采用地质调查与土壤氡测量相结合的方法,查明了区内控盆隐伏断裂的位置、产状、宽度等。调查结果与地貌和区域构造特征吻合较好,因此认为,土壤氡测量适用于山间盆地内隐伏活动断裂的调查。     

北京平原区隐伏断裂与氡浓度响应关系

北京地区隐伏断裂发育,NW及NE向断裂相互交汇,成为未来可能发生地震的构造。为了研究活动断裂与土壤氡浓度的响应关系,本次对北京平原区NW和NE向2条剖面进行了氡浓度测量。通过测试分析,基本查明了隐伏构造与土壤氡浓度的对应关系以及影响土壤氡浓度的相关地质因素。研究表明,活动断裂存在的区域氡浓度明显高于周边区域,且在构造复杂与活动性强的断裂区域氡浓度值变化更为明显;新生界厚度对氡的散逸强度存在一定的制约,北京地区新生界厚度与氡浓度水平成正相关;不同成土母质核素比活度不同,对区域氡浓度背景值亦存在影响。本次研究成果确定了隐伏断裂与土壤氡浓度的对应关系,以及新生界厚度和不同成土母质土壤对土壤氡浓度的影响,为今后在平原区开展隐伏断裂调查及氡浓度研究工作有重要借鉴和指导意义。     

中国大型走滑断裂的复位研究与油气资源战略选区预测

阿尔金断裂和郯庐断裂是亚洲大陆上规模最大的2条晚中生代以来活动的走滑断裂带,前者可能同步错移并分隔曾经统一的古生代克拉通盆地和侏罗纪箕状断陷的原型盆地,后者中段向北错移了属于扬子板块的苏北-胶东地块,北段佳(木斯)-依(兰)断裂切错了松辽与泛三江-哈巴罗夫斯克盆地,敦(化)-密(山)断裂左行错移了鸡西-七台河盆地和虎林盆地。因此,塔里木西南盆地油气资源的勘探评价应与柴达木盆地对比进行,巴丹吉林、腾格里沙漠掩盖下的阿拉善地块可与北塔里木地块对应,在其侏罗系—白垩系陆相盆地沉积之下可能保存了古生代克拉通沉积,可作为有潜力的油气资源战略选区;南黄海中部隆起带是苏北盆地建湖隆起的东向延伸,其震旦系—三叠系海相碳酸盐岩油气藏为潜在的勘探目标区;郯庐断裂北段的构造复位研究,对拓宽东北地区油气资源潜力区和重新认识松辽盆地形成背景、成盆机制有重大的理论与实践意义。     

中国大型走滑断裂的复位研究与油气资源战略选区预测

阿尔金断裂和郯庐断裂是亚洲大陆上规模最大的2条晚中生代以来活动的走滑断裂带,前者可能同步错移并分隔曾经统一的古生代克拉通盆地和侏罗纪箕状断陷的原型盆地,后者中段向北错移了属于扬子板块的苏北-胶东地块,北段佳（木斯）-依（兰）断裂切错了松辽与泛三江-哈巴罗夫斯克盆地,敦（化）-密（山）断裂左行错移了鸡西-七台河盆地和虎林盆地。因此,塔里木西南盆地油气资源的勘探评价应与柴达木盆地对比进行,巴丹吉林、腾格里沙漠掩盖下的阿拉善地块可与北塔里木地块对应,在其侏罗系-白垩系陆相盆地沉积之下可能保存了古生代克拉通沉积,可作为有潜力的油气资源战略选区;南黄海中部隆起带是苏北盆地建湖隆起的东向延伸,其震旦系-三叠系海相碳酸盐岩油气藏为潜在的勘探目标区;郯庐断裂北段的构造复位研究,对拓宽东北地区油气资源潜力区和重新认识松辽盆地形成背景、成盆机制有重大的理论与实践意义。     

From radon hazard to risk prediction-based on geological maps,soil gas and indoor measurements in Germany

Mapped geological units can be regarded as proxies standing for a complex series of subsoil geochemical and physical properties including the assigned radon activity concentration in soil gas, which is taken as best estimator of the regional geogenic radon potential. Areal distribution of measuring sites for soil gas in Germany is adapted to spatial variation of geology. A grid-based and distance-weighted interpolation procedure is applied, following geologically defined neighbourhood relations of measuring sites and accounting for isolated outcrops of known geology but without measurements. To investigate the statistical relationship between indoor radon, house type and building ground specifications, measurements of the indoor radon concentration have been carried out in more than 10,000 dwellings in different regions of Germany. Multiple regression analyses of variance reveal that besides region-specific geological properties and building characteristics, various house type and living style variables significantly contribute to the explained variance for ground floor radon concentrations. These parameters are also dominant in controlling the radon transfer relation from soil gas to indoor air. Risk prediction maps for radon in houses indicating the probability to exceed certain indoor threshold values can be useful especially for regions with no or only a few measurements of indoor radon.     

电成像与浅层地震联合在浅覆盖区隐伏断层探测中的应用

为了避免单一物探方法在地质反演解释中存在的多解性弊端,本文介绍了以电成像法为主、浅层地震反射波法为辅的综合物探方法对隐伏断层进行探测的应用实例,首先,通过电成像法查找断层破碎带的位置走向,然后利用浅层地震反射波法精确查明断层的产状、性质、位置及断距等地质参数,并对两种方法的探测成果进行综合对比分析,推断该隐伏断层为走向近东西向,倾向近南北向的正断层,断层落差约4.2m,其上断点埋深约17.9m。经钻孔验证表明,电成像与浅层地震联合方法在浅覆盖区隐伏断层探测中具有精确、可靠、经济的优势,该方法具有较强的应用价值。     

基于土壤氡气测量识别甘肃北山南缘隐伏断裂

我国高放废物地质处置库首选预选区位于甘肃北山南缘，区内分布有多条大型非活动断裂构造，这些断裂很可能成为未来放射性核素迁移的主要通道。断裂在向地表延伸过程中，受第四系覆盖等因素影响，造成关键构造部位隐伏地下而难以识别。本文以北山地区新场地段南部红旗山和前红泉断裂为研究对象，采用土壤中氡气测量方法，探讨了大型断裂构造中隐伏段落的识别及其指示的水文地质意义。结果表明：土壤中氡气测量对于识别北山南缘隐伏断裂具有很好的指示意义，是传统地质调查方法的一种重要补充；红旗山和前红泉断裂裂隙系统整体开启性均较差，裂隙系统不发育，影响范围较小，不具备形成较大规模储水空间的可能性。不同断裂带土壤氡浓度背景值差异较大，可根据土壤氡浓度累积频率分布图确定背景值；土壤氡浓度等值线分布图对判断隐伏断裂位置具有一定的指示作用。对于压剪性断裂而言，主断裂多沿氡气高异常与低异常边界分布或表现为氡气中等异常，而两侧的次级断裂表现为氡气高异常。     

壤中汞气测量在于都营脑隐伏矿产勘查中的应用

营脑矿区位于南岭银坑贵多金属矿田西部,以破碎蚀变岩型银多金属矿产为主.该区壤中汞气异常明显,最大含量为5 200.0 ng/m3,峰背比最高达60.4.汞气异常形态与区内NE向控矿破碎带分布基本一致,对含矿破碎带表现出异常叠加的特征.以汞气异常为依据,结合研究区成矿地质条件,综合固定出3个找矿远景区,并认为Ⅲ远景区找矿潜力最大.     

Spatial variability of soil properties in relation to land use and topography in a typical small watershed of the black soil region,northeastern China

Soil degradation resulted from unreasonable land use and erosion has been a serious problem in the black soil region of northeastern China. This paper seeks to understand the relationships between topsoil properties and topography and land use for land management targeting at improving soil quality in this region. A total of 292 soil samples and 81 volumetric rings were taken from a typical small watershed of the region in June 2005 for examining total carbon (TC), total nitrogen (TN), soil texture (classified into gravel, sand, silt, and clay), and bulk density (ρ _b), respectively. Spatial variability of these soil properties was evaluated with classical statistics and geostatistics methods. The results of classical statistics indicated that TC, TN, sand, silt, clay content, and ρ _b were moderate variables while gravel had great variability. Soil properties were mainly correlated to slope position, elevation and land types. Geostatistical analyses showed that the spatial autocorrelation for TC, TN, and silt was weak, strong for clay and moderate for and ρ _b sand, respectively. The spatial variations of soil properties are affected comprehensively by topographic factors, land use, erosion, and erosion control in this watershed. Past erosion, however, is the most important component to induce change of soil properties. In this small watershed, current soil and water conservation measures play an important role in controlling soil loss. But the restoration of soil properties was unsatisfactory. Comparing with untilled soil of this region, TC, TN, silt content are excessively low; whereas ρ _b, sand and clay content are excessively high; gravel appears at most sampling locations. It is necessary for improving soil properties to protect forest and grassland and change cultivation system of farmlands.     

天水地区主要活动断裂特征与氡气测试成果分析

断层氡气释放强度、范围、成分等的变化可以用来分析评价活动断层的相对活动性。研究了天水地区主要活动断裂的基本特征,并对这些断裂进行了氡气测试与分析。结果表明:西秦岭北缘断裂带的活动性为强—极强;礼县—罗家堡断裂的活动性为强;礼县—积石峡断裂的活动性为强—中等;清水断裂活动性为中等。该结果与活断层的活动强度较吻合,说明氡气测试成果可以作为一种断裂活动性的评价方法。      

Regional gravity survey and application in oil and gas exploration in China

Ground gravity survey for regional structure unit delineation and oil and gas exploration in China is addressed in this paper with examples. Gravity survey scales, coverage, technical regulations and achievements at the national level are introduced, including data processing and anomaly interpretation techniques. Bouguer anomalies of terrestrial territories of China and classification of anomalous feature zones are also described; they are well correlated with lithotectonical boundaries, fault zones, and unexposed igneous plutons. Recent study results of petroliferous sedimentary basins are presented as well, including concealed boundaries and major structures of large basins. It is concluded that gravity survey is the most effective and economic method in unveiling unexposed and deep-seated structures, targeting and delineating oil and gas-bearing sedimentary basins, and locating main trap structures within prolific basins in early stage of exploration in China. Suggestions for improving exploration of both conventional and unconventional oil and gas reservoirs in China are also given in the paper.     

东沙海域浅层沉积物硫化物分布特征及其与天然气水合物的关系

对南海东沙海域浅层沉积物中硫化物的含量进行了分析,结果表明,沉积物中硫化物的含量与沉积物顶空气甲烷含量有密切的关系,在存在顶空气甲烷高异常的沉积物岩心中,沉积物中硫化物含量明显高于无甲烷异常的沉积物岩心,且随层位深度的增加,其含量明显增大,存在显著的变化梯度带。碎屑矿物鉴定结果表明,沉积物中硫化物主要以黄铁矿的形式存在。浅层沉积物中高含量的硫化物与天然气水合物分解形成的甲烷流有直接的关系,反映了下部沉积物中可能存在天然气水合物。     

龙泉山断裂带隐伏断层氡气特征及其活动性分析

龙泉山断裂构造带作为龙门山推覆带的前陆隆起,严格控制了成都平原东边界,其活动性历来受到人们的关注。通过对龙泉山断裂带的氡气进行测量,可以有效地判断隐伏断层的位置及其活动性。测量结果显示,龙泉山断裂带北段东坡活动性强于西坡,主断层的活动性明显强于边缘隐伏断层,4条断层的活动性由强到弱依次为合兴场断层 > 红花塘断层 > 龙泉驿断层 > 松林场断层。龙泉山断裂带同一条断层在地表由多个破碎带组成,其氡气异常特征与断层活动性和破碎带特征呈正相关性,即断层活动性越强,氡气异常特征越显著。龙泉山断裂带氡气平均异常浓度是背景值的9.6倍,将各异常带峰值浓度与背景值进行对比分析,大致归纳出了龙泉山地区隐伏断层活动性的相对判别标准。     

东北地区油气领域接替形势展望 （代序）

东北地区存在5套油气勘探层系.松辽盆地内的白垩系松花江群坳陷层系是目前生产的主力,已进入稳产阶段后期.下白垩统的断陷层系仅在松辽、二连、海拉尔等盆地发现油气田,正处于勘探开发高潮期.以断陷为主体的下—中侏罗统含煤层系是待探索的新领域,可能在白垩系(甚至上侏罗统火山岩)覆盖下保存.近年来,东北地区上古生界的含油气远景已被广泛认可,并开展了选区评价工作.东北东部的新生界断陷含有丰富的煤、油页岩,其下可能有白垩系深埋,但受浅部火山岩的影响,对其深部的研究工作不足.针对以上5个领域的特点提出了今后的研究方向,特别强调了新领域开拓以及常规和非常规油气勘探并举.     

Characteristics of faults and their implications for oil and gas enrichment in the Liaoxi Depression,Bohai Bay Basin,eastern China

The faults that developed in the Liaoxi Depression can be classified into three types according to their extent and connectivity with the source and reservoir rocks (i.e. type I faults, type II faults and type III faults). These faults played different roles in controlling the basin geomorphology; the formation and evolution of the source rocks, reservoir rocks, cap rocks and traps; and the migration and accumulation of hydrocarbons in the Liaoxi Depression. Extending from the basement to the Neogene strata, type I faults, which are the largest in the basin, mainly controlled the development and basin-scale geomorphology; type II faults mainly controlled the sub-tectonic zones; and type III faults mainly controlled the formation and evolution of the traps. The movements of type I and type II faults during the hydrocarbon expulsion period were closely related to oil and gas migration. The rates of fault activity varied among the different sags of the Liaoxi Depression. Type I faults in both the northern and southern sags appear to have moved considerably during the hydrocarbon generation and expulsion stages, which strongly promoted hydrocarbon migration, whereas weakly active type I faults in the central sag made limited contributions to hydrocarbon migration. The sealing behaviour of the faults controlled the hydrocarbon migration directions and locations, and the good lateral sealing ability of the type I faults in the northern and southern sags confined the accumulation of hydrocarbons within the sags independently. However, the type I faults in the central sag partially opened laterally, which increased the likelihood of hydrocarbon migration from the sag centre to the uplift and reduced the likelihood of hydrocarbon accumulation within the sag centre. Therefore, the oil- and gas-enrichment patterns in the Liaoxi Depression are closely related to the characteristics of the faults, with traps near types I and II faults showing an increased likelihood of oil- and gas-field formation, as observed with the JZ9-3, LD4-2 and LD5-2 wells, and traps located in the sags remote from types I and II faults showing a reduced likelihood of oil and gas accumulation.     

苏北盆地高邮凹陷隐蔽性断层构造特征分析与预测

晚白垩世晚期—新生代发育的高邮凹陷,是苏北盆地南部典型富含油气的半地堑式断陷盆地,自南向北分为南断阶、深凹带与北斜坡。该凹陷复杂断裂构造系统与相应的沉积格局受印支期NEE向逆冲基底断层系与晚侏罗世伊泽纳崎板块高速斜向俯冲形成的NNE向左行平移基底断层系影响,同时受古近纪期间区域近SN向拉张应力状态控制。北斜坡东部花瓦构造带主体EW向正断层与NNE向隐蔽性断层发育了限制型、连接型、复合型3类隐蔽性断块圈闭模式,同时在平面上形成多种组合样式。通过研究花瓦区隐蔽性断块圈闭实例与有限差分法数值模拟,分析总结出高邮凹陷NNE向隐蔽性断层的成因机制与构造特征,并推断了5条隐蔽性断层发育带。     

塔里木盆地西部的新生代断裂活动

研究区以塔里木盆地西部的巴楚隆起为核心,包括其南侧的麦盖提斜坡和北侧的北部坳陷(阿瓦提凹陷)。这里新生代断裂异常发育。以鸟山-古董山地区为重点,通过精细的地震剖面解释,在塔里木盆地西部识别出5期新生代断裂活动,分别发生于:白垩纪末-古近纪初(ca.65Ma)、中新世末-上新世初(ca.5Ma)、上新世末-更新世中期(ca.3~1.5Ma)、更新世中-晚期(ca.1~0.1Ma)和全新世(ca.0.01Ma)。中寒武统和古近系膏盐层构成了研究区的2个主滑脱面。ca.65Ma的冲断受控于基墨里中间大陆与亚洲大陆碰撞的远程效应;ca.5Ma、ca.3~1.5Ma、ca.1~0.1Ma和ca.0.01Ma的断裂活动(包括滑脱断层、冲断层、走滑断层和正断层)均受控于印度-亚洲碰撞的远程效应。晚新生代(中新世以来)的断裂活动以脉动式冲断为特征,两次相邻脉动式冲断之间为时间不等的短暂的构造间歇期;间歇期构造平静,甚至可以形成正断层。     

中国东北地区油气地质特征与勘探潜力展望

中国东北地区发育50多个盆地,规模大小不一,较大的盆地包括松辽、二连、海拉尔盆地和5个跨境盆地。东北地区油气资源潜力巨大,油气储量增幅显著,同时面临油气上产、稳产难度仍然持续加大的现实。本文在深入分析东北地区构造与沉积古地理演化过程的基础上,总结了东北地区构造与沉积协同作用下的成藏组合差异发育特征。进一步结合勘探实践,针对油气勘探中存在的问题,围绕着新领域新层系的工作思路,提出了东北地区油气勘探的方向,包括:松辽盆地中央坳陷带中浅层油气精细勘探,松辽盆地南部深层火山岩油气勘探,松辽盆地西斜坡和北部倾末端油气勘探,东北地区古生界油气勘探,大三江盆地群油气勘探,东北地区页岩油和油页岩资源勘探。为未来东北地区油气资源的勘探部署提供了科学依据。     

定日县岗嘎地堑盆地隐伏断层氡气特征及其活动性分析

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