利用测井信息评价盐湖相烃源岩

盐湖相烃源岩富含膏、盐质成分,使其测井响应特征发生极大改变,给测井评价烃源岩带来困难。基于实测数据,分析了盐湖相烃源岩中普遍发育的纯泥岩、含膏(盐)泥岩和膏(盐)质泥岩有机碳含量的测井响应模式,发现纯泥岩和含膏(盐)泥岩TOC与AC和LogRt呈正比,与DEN呈反比,膏(盐)质泥岩TOC与DEN呈正比,与LogRt呈反比,并基于此建立了盐湖相烃源岩测井评价方法,即首先利用ΔGR区分岩性,再针对不同岩性建立TOC评价模型,最后根据实测S₁+S₂和TOC建立相关关系,就可以求取烃源岩的TOC和S₁+S₂。利用该方法对东营凹陷沙四下亚段烃源岩性质和展布进行分析,发现预测TOC与实测TOC吻合程度高,具有一定推广价值。     

中国昆明地区岩溶洞穴洞口带苔藓植物研究

为了研究中国西南岩溶洞穴植物区系与生物多样性特征, 作者曾两次对云南昆明地区12个岩溶洞穴进行了野外考察和苔藓植物标本采集工作。其中含昆明市石灰岩洞穴1个, 石林县石灰岩洞穴5个和宜良县白云岩洞穴6个。根据采自12个岩溶洞穴洞口带的164件苔藓植物标本研究, 本文首次报道昆明地区洞穴苔藓植物10科18属25种。昆明地区洞穴中分布较多的苔藓植物科有丛藓科( Po ttiaceae) 5属8种,凤尾藓科( Fi ssidentaceae ) 1属4种,柳叶藓科( Amblystegiaceae ) 3 属3 种和青藓(Brachytheciaceae ) 2属3种。溶洞中较常见的4种苔藓植物种类是萤光苔类植物光苔Cyathodiumcavernarum Kunze ( 见于6个溶洞中) , 小凤尾藓Fissidens bryoides Hedw ( 见于4个溶洞中) , 橙色净口藓Gymnostonum calcareum Nees et Ho rsch (见于3 个溶洞中)和长叶扭口藓Tortella tortuosa( Hedw ) Limp ( 见于3个溶洞中)。野外观察表明,受洞穴弱光环境生态因子的限制, 昆明地区洞穴苔藓植物主要生长于洞穴洞口0～ 26m带范围内; 2种丛集型藓类植物, 橙色净口藓Gymnostonumcalcareum Nees et Horsch, 和钩喙净口藓G.recurvirost re Hedw 参与洞口带钟乳石或石笋钙华沉积。      

Analysis on the deployment of mining research supported by the grant program of Deep Resources Exploration and Mining

The Deep Resources Exploration and Mining(DREAM) grant program, within the framework of The National Key Research and Development Program grants, is a pillar to implement China's science and technology strategy in the area of deep resources exploitation. To tackle the insufficient of theories and technologies for the 1000-meter-deep mining, a section of mining, covering the research of basic theories, general technologies and application demonstration, was arranged in the layout of DREAM under the principle of "whole chain design, integrated implementation". In the aspect of basic research, DREAM mainly focused on the deep rock mechanics and mining theory, such as the in-situ mechanical behavior of deep rock, deep high stress induction and energy regulation theory. For the general and key technologies, DREAM supported the research on the mine construction and hoisting, excavation, rock breaking, mining methods and mining safety according to the characteristics of coal and metal mines. For the demonstration application, taking green, safe and efficient as the starting point, DREAM aimed at the green, safe and high efficiency mining, and the demonstration and leading role projects such as the low-waste and high-efficiency back fill mining. Since 2016, 10 RD projects have been funded, and 122 institutional participants with a total budget of RMB 235 million from the central government and RMB 480 million from enterprises as well as local governments have been involved. It is expected that the mining section of DREAM would contribute to establishing the theory and technology system in the area of deep mining and promoting the ability of deep resource exploitation in China.     

Principles of Probabilistic Regional Mineral Resource Estimation

Five principal sources of uncertainty in quantitative mineral resource estimation are listed and illustrated by means of a simple example (mosaic model) and a case history study for large copper deposits in the Abitibi area of the Canadian Shield. Abitibi copper potential originally was estimated on the basis of 1968 estimates of production and reserves totalling 3.12 Mt Cu. This prognostication now could be evaluated on the basis of 2008 copper production and reserves totalling 9.50 Mt Cu. An earlier hindsight study performed on the basis of 1977 data (totalling 5.23 Mt Cu) showed seven new discoveries occurring either in the immediate vicinities of known deposits or on broad regional copper anomalies predicted from the 1968 inputs. By 1977, the global geographic distribution pattern of large copper deposits in the Abitibi area had stabilized. During the next 30 years, new copper was essentially found close to existing deposits, much of it deeper down in the Earth's crust. In this paper, uncertainties associated with copper ore tonnage are analyzed by comparison of 2008 data with 1968 data using (a) log-log plots of size versus rank, and (b) lognormal QQ-plots. Straight lines fitted by least squares on these plots show that 1968 slopes provide good estimates of 2008 slopes but 1968 intercepts are much less than 2008 intercepts. In each linear log-weight versus log-rank plot, the slope is related to fractal dimension of a Pareto frequency distribution, and in a lognormal QQ-plot it is determined by logarithmic variance. The difference between 2008 and 1968 intercepts represents the increase in copper ore production and reserves from 1968 to 2008. The Pareto model fits actual copper and massive sulphides increase over the past 40 years better than the lognormal frequency distribution model for 10 km×10 km cells on favorable environments in the Abitibi area.      

Application of 3D Static Modelling in Reservoir Characterization: A Case Study from the Qishn Formation in Sharyoof Oil Field, Masila Basin, Yemen

Three-dimensional(3 D)static modelling techniques are applied to the characterization of the Qishn Formation(Fm.)in the Sharyoof oil field locating within the Masila basin,southeastern Yemen.The present study was initiated by the seismic structural interpretation,followed by building a 3 D structural framework,in addition to analysing well log data and from these,3 D facies and petrophysical models are constructed.In the Sharyoof oil field,the Qishn Fm.exhibits depth values within the range of 400-780 m below sea level,with a general increase towards the SSE.A set of high dip angle normal faults with a general ENE-WSW trend dissect the rocks.The strata are also folded as a main anticline with an axis that is parallel to the fault trend,formed as a result of basement uplift.According to the facies models,the Qishn Fm.comprises 43.83% limestone,21.53% shale,21.26% sandstone,13.21% siltstone and 0.17% dolomite.The Qishn Carbonates Member has low porosity values making it a potential seal for the underlying reservoirs whereas the Upper Qishn Clastics SI A and C have good reservoir quality and SIB has fair reservoir quality.The Upper Qishn Clastics S2 and S3 also have fair reservoir quality,while the Lower Qishn Clastics zone has good reservoir quality.The water saturation decreases towards the west and east and increases towards north and south.The total original oil in-place(OOIP)of the Upper Qishn clastics is 106 million STB within the SI A,SIC and S2 zones.Drilling of development wells is recommended in the eastern study area,where good trapping configuration is exhibited in addition to the presence of a potential seal(Upper Qishn Carbonates Member)and reservoir(Qishn Clastics Member)with high porosity and low water saturation.     

印度共和国地质构造与区域成矿

印度共和国位于南亚次大陆中部,陆地面积297.32万km2(不包括印控克什米尔地区与锡金),北部为喜马拉雅高山区,海拔平均为5500m;中部是印度河-恒河-布拉马普特河(在中国境内称雅鲁藏布江)平原,平均海拔100~200m,是印度经济最发达、人口最稠密地区;南部是印度半岛高原区,西高东低,     

多年冻土环境对寒区天然气管线稳定性的影响

Field investigations of several gas mains in different geosystems were carried out in Noviy Urengoy region (Eastern Siberia) in September, 2003. There were on ground pipelines covered with peat or sand. In case of small rivers pipelines were elevated by pile support on the shores. Because pipelines were applied in cryolithozone that means special secure methods used in pipeline systems functioning and operating. There are multiple sites of natural landscapes destructed or totally destroyed during building and exploiting of the pipelines. That causes negative cryogenic processes development. The most dangerous one is the heaving, that reaches up to several meters in humid landscapes. The complex thermoerosion, thermokarst and heaving occur very often at one site. The heaving of piles leads to pipe deformations and the emergency situations to occur. It is possible to predict negative cryogenic processes development and so far to reduce an emergency risk.     

Magmatic and hydrothermal zircon growth during multiple orogenic cycles in an evolving mantle wedge

The Hongseong area of the Hongseong-Imjingang Belt in the central-western Korean Peninsula forms part of a subduction-collision system that is correlated with the Qinling-Dabie-Sulu Belt in China. Several serpentinized ultramafic bodies carrying blocks of metamorphosed mafic rocks occur in this area. Here we investigate zircon grains in serpentinites from Bibong(BB) and Wonnojeon(WNJ), and high-pressure(HP) mafic granulite from Baekdong(BD) localities based on U-Pb, REE and Lu-Hf analyses. The zircons from BD HP mafic granulite show distinct age peaks at 838 Ma, 617 Ma and 410 Ma, with minor peaks at1867 Ma, 1326 Ma and 167 Ma. The Neoproterozoic age peaks in these rocks as well as in the serpentinites suggest subduction-related melt-fluid interaction in the mantle wedge at this time. The older zircon grains ranging in age from the Early to Middle Paleoproterozoic might represent detrital grains from the basement rocks transferred to the wedge mantle through sediment subduction. The BD HP mafic granulite shows a Middle Paleozoic age peak(Devonian; 410 Ma). The 242-245 Ma age peaks in the compiled age data of zircon grains serpentinites from BB and WNJ correspond to a major Triassic event that further added melts and fluids into the ancient mantle wedge to crystallize new zircons. In the chondrite normalized rare earth element diagram, the magmatic zircon grains from the studied rocks show LREE depletion and HREE enrichment with sharply negative Eu and Pr anomalies and positive Ce and Sm anomalies. The REE patterns of hydrothermal zircons show LREE enrichment, and relatively flat patterns with negative Eu anomaly. Zircon Hf signature from the WNJ serpentinite show negative εHf(t)(-18.5 and-23.5) values indicating an enriched mantle source with TDM in the range of 1614 Ma and1862 Ma. Zircons from the BD HP mafic granulite also show slightly negative εHf(t)(average-4.3) and TDM in the range of 1365-1935 Ma. Our study provides evidence for multiple zircon growth in an evolving mantle wedge that witnessed melt and fluid interaction during different orogenic cycles.     

Advanced reliability analysis of slopes in spatially variable soils using multivariate adaptive regression splines

This study aims to extend the multivariate adaptive regression splines(MARS)-Monte Carlo simulation(MCS) method for reliability analysis of slopes in spatially variable soils. This approach is used to explore the influences of the multiscale spatial variability of soil properties on the probability of failure(P_f) of the slopes. In the proposed approach, the relationship between the factor of safety and the soil strength parameters characterized with spatial variability is approximated by the MARS, with the aid of Karhunen-Loeve expansion. MCS is subsequently performed on the established MARS model to evaluate Pf.Finally, a nominally homogeneous cohesive-frictional slope and a heterogeneous cohesive slope, which are both characterized with different spatial variabilities, are utilized to illustrate the proposed approach.Results showed that the proposed approach can estimate the P_f of the slopes efficiently in spatially variable soils with sufficient accuracy. Moreover, the approach is relatively robust to the influence of different statistics of soil properties, thereby making it an effective and practical tool for addressing slope reliability problems concerning time-consuming deterministic stability models with low levels of P_f.Furthermore, disregarding the multiscale spatial variability of soil properties can overestimate or underestimate the P_f. Although the difference is small in general, the multiscale spatial variability of the soil properties must still be considered in the reliability analysis of heterogeneous slopes, especially for those highly related to cost effective and accurate designs.     

Analysis on the law of occurrence of shallow geothermal energy in Zhoukou City of Henan Province,China

In this paper,through data collection and field investigation,the development and utilization status of shallow geothermal energy in Zhoukou urban area was discussed.Based on the analysis of hydrogeological conditions,rock and soil structure characteristics and field test research,the spatial distribution characteristics of rock and soil in the study area were summarized.The study shows that Zhoukou City is located in the alluvial plain of Huanghuai,and the loose deposits of river alluvial genesis range 0-200 m.These loose deposits and groundwater stored in their pores are the main carriers of shallow geothermal energy.In the central part of the Yinghe River in the middle of the study area,the aquifer thickness is within 200 m,the particle size is coarser,the water-bearing degree and recharge capacity is better.On this basis,the paper uses AHP to evaluate the suitability of shallow geothermal energy development and utilization to guide the rational development and utilization of shallow geothermal energy resources.     

Une Microflore du Barrémien dans la Province de Valencia,Espagne

A Barremian microflora is recorded in the terrigenous facies (Weald) of the Lower Cretaceous in the northern region of the Province of Valencia (Spain), these beds have been poorly dated up to now due to the absence of fossils. The Villar del Arzobispo microflora correspond unquestionably to the Barremian-Aptien period, but the numerical importance of derived forms from the Jurassic, the remarkable variety of forms of Cicatricosisporites, and the rareness of pollen of Angiosperms, indicate a Barremian age to be more likely.This discovery permits us to establish the stratigraphical relationship of this terrigenousfacies of Villar del Arzobispo with the dated “Weald” of other areas of the Iberian Chain and to give a complete chrono-stratigraphical interpretation to the different litho-stratigraphical units that constitute the Lower Cretaceous of this region.     

Geochemistry and petrology of Mesozoic-Cenozoic magmatic complexes of the southern framing of the Aldan shield: Geodynamic problems

This paper summarizes the results of long-term geological, petrological, and geochemical investigations of the Mesozoic-Cenozoic complexes of the Stanovoy Range in order to determine the main reasons for their generation and evolution. The analysis of this material showed that the compositionally variable Late Mesozoic igneous complexes of the Stanovoy Range were formed in various depth facies, from abyssal to surficial. The majority of their salic complexes show minor compositional variations, whereas the mafic complexes are more variable, especially in the southeast of the region. The southeastern Stanovoy Range comprises comparable amounts of both subalkaline and low-alkali igneous rocks, whereas the central part is dominated by subalkaline rocks, and the northwestern part contains rocks only of the shoshonite-latite series. This zoning is fundamentally different from that of typical island arcs, which are characterized by the occurrence of volcanic rocks of similar alkalinity in each zone. Extrusive and intrusive rocks with similar alkali and silica contents (and schlieren-like inclusions in the granitoids of the region) were formed from common magmas of corresponding chemical compositions. In addition, the mafic and most of the salic magmas were formed as independent melting products, whereas the magmas of intermediate composition were formed mainly by mixing of chemically contrasting liquids (i.e., salic and basic). It was shown that the available information on the magmatism of the region is best interpreted in terms of the model of mantle diapirism. In particular, mantle diapirs ascended rather slowly during the Mesozoic and occurred over the whole territory of the Stanovoy Range during the Jurassic-Cretaceous stage (J₃-K₁), when alkaline and subalkaline basalts were formed. During the Early-Late Cretaceous stage, mantle diapirs produced alkali-poor basalts in the central and eastern parts. During the Cenozoic, the diapir ascended rather rapidly but only in a small area in the eastern part of the region forming alkali basalts. In contrast to the Cenozoic, the Earth’s crust was strongly affected by mantle diapirs and related mafic magmas in the Mesozoic. As a result, crustal sequences were reworked by fluids and subsequently yielded tremendous volumes of compositionally corresponding salic magmas, which interacted and mixed with mafic magmas producing the corresponding chemical zoning. The maximum generation of crustal magmas was confined to the axial zones of ascending diapirs, where the highest energy effects took place, whereas the role of autochthonous gneissic granites increased away from the axis at the expense of typical intrusive complexes.     

Statistical considerations for grain-size analyses of tills

Relative percentages of sand, silt, and clay from samples of the same till unit are not identical because of different lithologies in the source areas, sorting in transport, random variation, and experimental error. Random variation and experimental error can be isolated from the other two as follows. For each particle-size class of each till unit, a standard population is determined by using a normally distributed, representative group of data. New measurements are compared with the standard population and, if they compare satisfactorily, the experimental error is not significant and random variation is within the expected range for the population. The outcome of the comparison depends on numerical criteria derived from a graphical method rather than on a more commonly used one-way analysis of variance with two treatments. If the number of samples and the standard deviation of the standard population are substituted in at-test equation, a family of hyperbolas is generated, each of which corresponds to a specific number of subsamples taken from each new sample. The axes of the graphs of the hyperbolas are the standard deviation of new measurements (horizontal axis) and the difference between the means of the new measurements and the standard population (vertical axis). The area between the two branches of each hyperbola corresponds to a satisfactory comparison between the new measurements and the standard population. Measurements from a new sample can be tested by plotting their standard deviation vs. difference in means on axes containing a hyperbola corresponding to the specific number of subsamples used. If the point lies between the branches of the hyperbola, the measurements are considered reliable. But if the point lies outside this region, the measurements are repeated. Because the critical segment of the hyperbola is approximately a straight line parallel to the horizontal axis, the test is simplified to a comparison between the means of the standard population and the means of the subsample. The minimum number of subsamples required to prove significant variation between samples caused by different lithologies in the source areas and sorting in transport can be determined directly from the graphical method. The minimum number of subsamples required is the maximum number to be run for economy of effort.     

Connectivity of a network of random discontinuities

Discontinuities such as fractures or cracks are common in geo-materials. Connectivity is a comprehensive parameter that includes the influence of length, orientation and density of the discontinuities. The main objectives of this paper are to define connectivity based on the statistical geometrical parameters of a network of random discontinuities and to quantify the hydraulic properties of the network using connectivity. An analytical method is first proposed to evaluate connectivity through the density of degree of freedom (DDOF). The analytically estimated DDOF is verified using numerical analysis. DDOF increases with the increases in the mean length, relative orientation and density of the random discontinuity network. Connectivity becomes better and the permeability becomes larger with increasing DDOF. The representative element volume (REV) of a random discontinuity network can be estimated based on connectivity. When a discontinuity network is poorly connected, a REV does not exist when the size of the discontinuity network is smaller than 10 times of the mean length of the discontinuities. When a discontinuity network is normally connected, a REV exists when the REV size is smaller than 10 times of the mean length of the discontinuities. When the discontinuity network is highly connected, the REV size is only 2–4 times of the mean length of the discontinuities. The results indicate that DDOF is a good indicator to quantify the connectivity of a random discontinuity network and the relationship between connectivity and permeability.     

Stress-strain analysis of geogrid-supported liners over subsurface cavities

Summary Finite element analyses were conducted to investigate the magnitude of tensile strains imposed on landfill liners due to the formation of subsurface cavities. The study incorporated the significance of using geogrids to reduce the magnitude of strains and possibly the potential for collapse of landfill liners. Variations of key parameters included depth of overburden (D) and diameter of the cavity (B). Estimated stress distributions were compared to theoretical values obtained from a model reported in the literature. Results indicated that, contrary to conventional wisdom, the critical area based on the mechanics of arching was above the edge of the cavity where stress concentration occurred. Incorporation of geogrid reinforcement reduced the magnitude of tensile strains. The tensile force in the geogrid was dependent upon the size of the cavity, the depth of the overburden, and the applied pressure.     

贵州罗甸二叠纪末生物大灭绝事件后沉积的微生物岩时代和沉积学特征

二叠纪末期发生的显生宙以来最大的生物绝灭事件,使海洋生态系统和陆地生态系统均受到重创之后,微生物岩广泛分布于全球正常浅海地区。研究认为,扬子地台在二叠纪末期存在一次海平面降低的事件,造成研究区二叠纪地层与早三叠世微生物岩之间存在沉积间断或剥蚀,并使三叠纪牙形石混入二叠纪末期的沉积物中。二叠-三叠系界线位于微生物岩层的底界;微生物岩形成于早三叠世最早期,相当于Hindeodus parvus带,是早三叠世最早期开始的海侵事件为其提供生长所需的可容纳空间。在Isarcicella staeschei带-I. isarcica带早期再次发生相对海平面降低事件,之后海平面开始快速上升。研究区早三叠世早期的微生物岩以凝块构造发育为特征,具有斑状、层状、枝状和网状凝块构造4种典型中型构造。结合前人的工作,认为微生物群落通过生物沉积和物理沉积作用形成球状体,球状体汇聚形成不同的中型凝块构造。研究扬子地台早三叠世凝块石的确切时代和结构、构造类型特征,为准确恢复生物大灭绝事件前后的环境变迁以及生物演化事件与环境变化的相互作用关系提供重要的证据。     

Lipid geochemistry of a post-glacial lacustrine sediment

The post-glacial environmental history of Voua de la Motte, a small pond, was studied by the lipid geochemistry of a 6 m long core. Palynological studies show that the deepest part of the core goes back to 10,000 yr BP corresponding to the time of formation of the lake following the retreat of the Rhodanian glacier. Hydrocarbons, aldehydes, linear alcohols, sterols, monocarboxylic and monohydroxy fatty acids, were determined throughout the core both in the free and bound lipid fractions, as well as in the tightly bound fraction for the carboxylic acids. There is no clear evidence of a transformation from the unbound to the bound form, except perhaps for the α-hydroxy acids.Qualitative as well as quantitative fluctuations in the distributions of these lipid classes were observed upward in the core. An attempt is made to correlate these fluctuations with the bioenvironmental and climatological evolution of the Basin on the basis of information obtained from palynology.     

Paleoenvironmental changes in the northern shelf of the Sea of Okhotsk during the Holocene

The combined micropaleontological (spores and pollen, diatoms, benthic foraminifers), lithologic, and isotopic-geochemical analysis of sediments from the northern shelf of the Sea of Okhotsk recovered by hydrostatic corer from the depth of 140 mbsl elucidated environmental changes in this part of the basin and adjacent land areas during the last 12.7 thousands cal. years. Geochronological scale of the core is established using the acceleration mass-spectrometry method for radiocarbon dating of benthic Foraminifera tests. The first insignificant warming in the northern part of the sea after glaciation occurred in the mid-Boreal time (9.6 ka ago) but not at the onset of the Holocene. The strongest warming in the region took place in the mid-Atlantic epoch to reach climatic optimum in the second half of the Subboreal (6 to 2.5 ka ago). A cooling in the northern shelf and adjacent land areas is established at the beginning of the Subatlantic (2.5 ka). A comparison of results obtained for Core 89211 with dated hydrological and climatic changes in central and southern parts of the Sea of Okhotsk (Gorbarenko et al., 2003, 2004) is used for a high-resolution analysis of climatic fluctuations in the study region and other areas of the basin during deglaciation and the Holocene.     

Aussiedler migration and its impact on Braşov's ethnic German population and built environment

The expression of different ethnic identities in the landscape is a product of the creation, destruction and preservation of the built environment. This may illustrate the changing processes over the evolution of a landscape. In the case of Braşov, Romania, it is possible to see in the urban landscape a reflection of the changing nature of the relationship between the ethnic German and Romanian populations, and the German and Romanian governments. This paper will demonstrate the persistence of ethnic German culture in the built environment and social organisation of Braşov in spite of the exodus of the ethnic German population. This revised version was published online in July 2006 with corrections to the Cover Date.     

湖南张家界溹水河谷与流域形态特征及其地貌意义

利用数字高程模型(DEM)数据、地形图、地质图数据结合实地踏勘,分析并计算了张家界地貌主要分布区溹水流域河谷形态特征和侵蚀积分值(HI),探讨了流域地貌侵蚀发育阶段特征。研究发现:溹水干流比降沿程基本上逐渐减小,纵剖面呈上凹形,凹度值约为0.70;主要支流比降明显大于干流,凹度值介于0.12～0.98;溹水干流河谷宽度和宽深比沿程向下表现出上升趋势、深度表现出下降趋势;溹水河谷横剖面凹度值上游较低,中游较高,近河口又降低,平均值约为0.63,都大于0.5;上中游主要支流河谷相对窄深,下游支流河谷相对宽浅;支流河谷横剖面的凹度值变化范围较大,平均值大于0.50。说明这一地区在地壳迅速抬升之间有较长时间地壳相对稳定,横向侵蚀形成一定宽度的河漫滩,河谷为U型谷,地貌发育处于壮年期或壮年期的中晚期。河谷侧蚀,河谷凹度值大于0.5,是张家界地貌独立峰柱得以形成的重要条件;溹水流域上游下段和中游HI值较高,下游HI值较低,最高值出现在天子山周围;没有发现地势和基岩特性对溹水流域HI值分布存在显著影响;张家界砂岩峰林地貌发育地区集中于溹水上游下段和中游上段的泥盆系砂岩分布区,这一地区HI平均值为0.46,处于地貌侵蚀旋回的壮年期。