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101.
Xin Li Dongliang Wang Baoquan Liu Chunling Ren Jianying Guo Xuefeng Su Jian Wang 《中国地球化学学报》2008,27(4):412-419
The northern margin of the Qaidam Basin is one of the main oil-gas exploration areas in western China, where source rocks are composed mostly of Middle and Lower Jurassic dark mud shale, carbargillite and coal. A large number of subsurface and outcrop samples differing in lithology with different types of organic matter were selected for resource evaluation, research and calculation. And among them, 13 samples were used for simulation experiment on hydrocarbon generating potential of various source rocks. At first, two kinds of heating modes were compared through simulation experiment, including single temperature-step heating and continual heating. Perhaps, the process of hydrocarbon generation and expulsion occurred naturally between a close system and an open system. In addition, the first heating mode was convenient, and all its reaction products were involved in the whole thermal evolution, and the final simulation experimental results were basically in consistency with the natural evolution trend Therefore, the first heating mode was adopted and the hydrocarbon yield of every sample was worked out. According to the type and lithology of organic matter and the hydrocarbon yield of samples for simulation experiment, hydrocarbon generation and expulsion mode with three kinds of lithology and five types of source rock has been established to provide the basis for hydrocarbon generation evaluation, research and resource calculation. 相似文献
102.
Three-dimensional modelling from single images remains an interesting topic of investigation in the research community, even though range sensors are becoming a common alternative for the generation of 3D information. The interest in single-image-based modelling is motivated by a wide spectrum of applications such as cultural heritage, civil engineering, urban planning and even criminology. In this paper a complete new production flowline is presented for modelling based on a single image. The modelling process consists of a series of familiar steps in photogrammetry and computer vision: feature extraction, vanishing point computation, camera self-calibration, 3D reconstruction and dimensional analysis. In particular, the methodology developed for single-image-based modelling takes a scientific approach combining several proven techniques with robust estimators. Finally, in order to demonstrate its capabilities, the reported examples include several real situations applied in different contexts. 相似文献
103.
通过对呼伦贝尔市煤矿地质环境敏感性的综合评价,结合当地实际情况,提出了以修筑拦挡建筑物、支撑与坡面防护、锚固、排水、选择更合理的开采工艺等技术手段,对该地区地质灾害进行防治的方案。方案对海拉尔河河道治理、生物措施、井下回填工程、加固边坡、抽排水、发展煤矸石砖厂、移民避让、招商引资8个部分提出了防治方法,促进地质环境治理工作的进行。 相似文献
104.
Spin rate estimation of sounding rockets using GPS wind-up 总被引:2,自引:1,他引:1
Carrier phase wind-up is a well-known effect that arises from the relative rotation between a transmitting and receiving antenna.
In GPS measurements at L1 frequency, this effect translates into an error of 19.029 cm per full relative rotation of antennas.
Since this effect is independent of the satellite elevation for pure rotation about the antenna boresight axis, it is usually
absorbed by the clock estimation in navigation algorithms. Therefore, the impact of wind-up is usually neglected for applications
that do not require accuracies to the cm level like RTK. However, in receiving platforms with high rotation rate, the accumulated
wind-up value can be important and actually be larger than receiver noise or even ionospheric variations. Therefore, in such
scenarios, the wind-up contribution can be isolated and used as a source of information to compute the spin rate of such platforms
using an appropriate combination of GPS observables. This work shows some results of a coarse, yet simple, approach to monitor
the rotation angle and spin-rate of spin stabilized sounding rockets flown by DLR. 相似文献
105.
106.
Large-scale ancient landslides of the area of more than 5 km2 and volume exceeding 200 × 106 m3 are characteristic features of the valleys incised in the northern periphery of the Crimean Mountains (Ukraine). The largely
affected area is located in the outermost cuesta range of the Crimean Mountains which consists of rigid Sarmatian limestones
overlying weak Middle Miocene and Upper Palaeogene deposits. A giant landslide arose in the Alma water gap as a reflection
of several coincident preparatory factors such as suitable bedrock stratification, smectite-rich bedrock exposed to swelling
activity, presence of faults parallel to the valley trend, and river capture event which preceded the landslide event. The
occurrence of such ancient megaslides is particularly interesting in the area which is characterized by low precipitation
(<500 mm/year) and weak contemporary seismicity. It probably reflects a more dynamic environment in humid phases of the Holocene;
however, seismic triggering along the Mesozoic suture zone cannot be rejected. Compressional features such as gravitational
folds in the central and distal parts of the landslide, which probably correlate with the whole landslide genesis or its significant
reactivation, arose, according to the radiocarbon dating, during the Holocene climatic optimum in the Atlantic period. The
slope deformation has been relatively quiescent since that time, except minor historic reactivization which took place in
the frontal part of the landslide. We suppose that the studied landslide could be classified as a transitional type of slope
deformation with some signs of spreading and translational block slides. 相似文献
107.
Tamás Mikes Dominik Christ Rüdiger Petri István Dunkl Dirk Frei Mária Báldi-Beke Joachim Reitner Klaus Wemmer Hazim Hrvatović Hilmar von Eynatten 《Swiss Journal of Geoscience》2008,101(1):31-54
Sandwiched between the Adriatic Carbonate Platform and the Dinaride Ophiolite Zone, the Bosnian Flysch forms a c. 3000 m thick, intensely folded stack of Upper Jurassic to Cretaceous mixed carbonate and siliciclastic sediments in the Dinarides. New petrographic, heavy mineral, zircon U/Pb and fission-track data as well as biostratigraphic evidence allow us to reconstruct the palaeogeology of the source areas of the Bosnian Flysch basin in late Mesozoic times. Middle Jurassic intraoceanic subduction of the Neotethys was shortly followed by exhumation of the overriding oceanic plate. Trench sedimentation was controlled by a dual sediment supply from the sub-ophiolitic high-grade metamorphic soles and from the distal continental margin of the Adriatic plate. Following obduction onto Adria, from the Jurassic–Cretaceous transition onwards a vast clastic wedge (Vranduk Formation) was developed in front of the leading edge, fed by continental basement units of Adria that experienced Early Cretaceous synsedimentary cooling, by the overlying ophiolitic thrust sheets and by redeposited elements of coeval Urgonian facies reefs grown on the thrust wedge complex. Following mid-Cretaceous deformation and thermal overprint of the Vranduk Formation, the depozone migrated further towards SW and received increasing amounts of redeposited carbonate detritus released from the Adriatic Carbonate Platform margin (Ugar Formation). Subordinate siliciclastic source components indicate changing source rocks on the upper plate, with ophiolites becoming subordinate. The zone of the continental basement previously affected by the Late Jurassic–Early Cretaceous thermal imprint has been removed; instead, the basement mostly supplied detritus with a wide range of pre-Jurassic cooling ages. However, a c. 80 Ma, largely synsedimentary cooling event is also recorded by the Ugar Formation, that contrasts the predominantly Early Cretaceous cooling of the Adriatic basement and suggests, at least locally, a fast exhumation. 相似文献
108.
Stephen V. Smith Silvia E. Ibarra-Obando Victoria Díaz-Castañeda Francisco Javier Aranda-Manteca José D. Carriquiry Brian N. Popp Oscar Gonzalez-Yajimovich 《Estuaries and Coasts》2008,31(4):719-727
Sediment grain size and organic carbon (OC) data collected over the past 50 years, together with δ13C values of OC in recently collected samples, were analyzed to improve understanding of sediment OC distribution and abundance in Todos Santos Bay. Sediments in the submarine canyon at the mouth of the bay and in quiet-water locations along the shore are fine grained, high in OC, and have generally low δ13C values; sediments in high-energy environments are low in OC and have high δ13C values. A bivariate isotopic mixing model indicates that none of the sediments contain >50% terrigenous OC (average ~30%), and that the terrigenous OC content of the sediments is a small proportion of the OC content of local soils. Sediment OC composition is apparently controlled by energy-related sorting and deposition, oxidation of much of the original terrigenous OC, and replacement of some terrigenous OC by marine OC. 相似文献
109.
Based on four UK Schmidt Telescope (UKST) IIIa-j direct plates which had been digitized by the Automated Plate Measuring System (APM), a detailed identification of the disk galaxies in the Virgo cluster has been carried out. The certain and possible member galaxies are mainly selected from the updated Catalogue of 2096 Galaxies in the Virgo Cluster Area (VCC). The area of this identification covers a 85 square degree region centered on this cluster. As a result, we compiled a new catalogue of 340 certain and possible member disk galaxies, including 85 lenticulars (SO), 136 spirals (S) and 119 irregulars (Irr), where the APM-measured values of the position angle (P.A.) and diameters of 299 disk galaxies are provided. For at least 149 galaxies, the values of the P.A. and diameters are published for the first time.Comparison between the APM-measured P.A. and diameters of galaxies and those given by the Uppsala General Catalog of Galaxies (UGC) demonstrates the reliability of our data. The statistical properties and completeness of this database are also discussed. Compared with the UGC-given P.A. and diameters which were determined by eyes, our data has no selection effect owing to the instrument measurements. Within our searching region, this might be the largest and relatively complete photometric database published so far for investigating the spatial orientation of the spin vectors of galaxies in the Virgo cluster. 相似文献
110.
A quadtree-based image segmentation procedure (HQ) is presented to map complex environmental conditions. It applies a hierarchical nested analysis of variance within the framework of multiresolution wavelet approximation. The procedure leads to an optimal solution for determining mapping units based on spatial variability with constraints on the arrangement and shape of the units. Linkages to geostatisiics are pointed out, but the HQ decomposition algorithm does not require any homogeneity criteria. The computer implementation can be parameterized by either the number of required mapping units or the maximum within-unit variance, or it can provide a spectrum of significances of nested ANOVA. The detailed mathematical background and methodology is illustrated by a salt-affected grassland mapping study (Hortobágy, Hungary), where heterogeneous environmental characteristics have been sampled and predicted based on remotely sensed images using these principles. 相似文献