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The paper presents results of palynological studies of the coal-bearing Carboniferous in Central Kazakhstan. A quantitative dynamics of major genera of miospores reflects an overall succession of the Carboniferous miospore assemblages. Viséan Serpukhovian assemblages are dominanted by Lophozonotriletes fuscatus,Acanthozonotriletes cristifer,A. inclusus,Punctatisporites glabratus,Crassispora ignorata,C. scrupea,Cyclobaculisporites trichacanthus,Lycospora breviapiculata,L. echinata and Vallatisporites decrescens. Rare Punctatisporites bertschoguriensis,Stenozonotriletes marginellus,Vallatisporites appilicatus,Verrucosisporites scrobiculatus, Reticulatisporites cancellatus,Granulatisporites arcuatus are recorded,which are not found in assemblages from overlying sediments. Bashkirian--Moscovian assemblages are dominated by Lycospora subtriquetra,L. pusilla, Vallatisporites ciliaris,Apiculatisporis mollis,Cyclogranisporites testiculatus,Calamospora microrugosa,Schopfipollenites principalis,Psilohymena psiloptera,Florinites grandis and Granulatisporites piroformis miospores. Cristatisporites latispinus,Angulisporites didymus,Thymospora obscura and Torispora securis are also present,as well as single Apiculatisporis curvispinus,Raistrickia inordinata,Marsupipollenites retroflexus,Entylissa caperata, Potonieisporites grandis and Cordaitina sp. A similar succession of miospore assemblages is recorded in the Carboniferous deposits of Europe and North America,which allows carrying out correlations,despite an endemic characters of many species of Paleozoic miospores from the coal-bearing Carboniferous of the Kazakhstan Province in the Euramerian Paleofloristic Region.
The Early Cretaceous flora from the coal-bearing strata ( Ussuri and Lipovtsy formations) in the Markovsky peninsula of South Primorye,Far East Russia,is reported in some detail in this paper. The flora containing over 80 species of about 50 genera can be divided into two assemblages. The paleofloristic characteristics and the comparisons of this flora with its coeval floras from the adjacent region of the eastern Heilongjiang of Northeast China,indicate the flora and its coal-bearing strata of the Markovsky peninsula can be compared to those of the Chengzihe and Muling formations of the Jixi area of Heilongjiang,representing probably the late Barremian and Aptian age,respectively.
In the Middle Jurassic,a large-scale tectonic-magmatic activities and hydrothermal mineralization occurred in the eastern Jilin province. The deposit types consist of the orogenic gold deposit,porphyry molybdenum deposit and skarn gold deposit,etc. ,which constitute regional hydrothermal metallogenic series. The magmatic bodies related to mineralization belong to calc-alkaline series,which are characterized by active continental margins. The above-mentioned different types of deposits formed in a uniform tectonic setting,which resulted from the combined processes between the subduction of Pacific plate under the Eurasia plate and the persistent post-collisional convergent forces between the North China plate and the Siberian plate. The mineralizations were happening in the deceleration period,after which Paleo-Pacific plate was strongly subducted under the Eurasia continental block,i. e. transition period from compression to extension.
By means of microscopy and laser Raman spectroscopy,the authors studied the fluid inclusions in petrography. The results show that there exist three-phase CO2-bearing and two-phase aqueous inclusions in gold ore; the fluid of NaCl--H2O--CO2 system went through immiscibility in ore-forming process. Ore-forming fluids were of low salinity ( 0. 82%--5. 40% NaCleqv) ,low density ( 0. 54-0. 93 g /cm3 ) ; mineralization temperature were concentrated in 320℃--340℃,with ore-forming pressure in 62-126 MPa and mineralization depth in 6. 34-9. 35 km. The fluid inclusions in quartz are generally characterized by a small amount of CO2 and N2 . Combined with recent results of the isotopic analysis for fluid inclusions and dating data,it was indicated that the main ore-forming fluids derived mainly from source of mantle-derived fluids with a small amount of magmatic fluid and meteoric water. The genetic type was mesothermal gold deposits involved by mantle-derived fluids.
Panorama field geological image is an important form of displaying field geology information with high resolution. Taking an example for Xingcheng,the authors studied the use of panorama field geological images based on the Flex for rich client display technology,application of Google maps API for Flash,and discussed construction method for field geological panoramic information system which created the rich client Internet application program. The results indicate that using Google maps API to mark position and route of panoramic image collection point can be fully integrated field geological information and map information. It can provide visual field geological information for users. This program is characterized by quick execution speed,strong interaction and rich function,which promotes the users' experience effectively.
In the current theory of bridge foundation design,all of the loads above the cap are loaded by the pile,and the bearing capacity of the soil among piles is not taken into account. In order to analyze the bearing capacity of the soil among piles in bridge pile foundation,a model of pile foundation is established based on a bridge foundation which is under construction,and by the finite element analysis software ANSYS. According to the results of finite element analysis ( FEA) and current bridge foundation design theory,a feasible composite pile foundation which can be applied in the design of bridge foundation,is recommended. Additionally,a number of modifications are made to the original design. It was confirmed that these modifications derived from numerical simulations can improve the performance of the foundation.
Glacier-lake outburst debris flow ( GLODF) ,unique in high altitude mountains where modern glacier is active,is significantly large in its scale of time and space,and strong in power of destroy. Following the world's becoming warmer,GLODF frequency gradually rises. In late years,quantitative estimation methodologies has been put into use of mass GLODF estimations. To improve former methodologies,this article suggests that the glacier ( or the massif) on the trailing edge and the moraine dam are the two major systems providing independent glacier lake outburst possibilities. Bucket Effect exists in GLODF issues. Therefore focusing on the relatively unstable one of the above two provides better accuracy in estimation on GLODF possibility. Thus,this article summarizes method of presort through specific GLODF evaluation.
Determination of water saturation is important for reservoir evaluation. When complex pore structures such as fracture and cavity are present in reservoir,Archie equation is no longer suitable. According to different models of pore structure division,the authors studied water saturation computation models. The results show that dual porosity system is divided into four models. The first model is based on dual laterolog,the second is Dual Porosity Ⅰ,the third is Dual PorosityⅡ,and the last one is based on the conductive pore. Besides,the triple porosity system is triple porosity model. Compute water saturation was using all the above five models in volcanic reservoir in Songnan gas field. The triple porosity system is the most suitable model for water saturation computation in complex pore structure volcanic reservoir.
The study examines the changes of land cover /use resources for the period under investigation. An unsupervised vegetation classification is being performed that provides five distinctive classes and thus assesses these changes in five broad land cover classes-high /moist forests,forest regrowth,mixed savanna,bare land / grass and water. The remote sensing images used in this work are both images of TM and ETM + in different time periods ( 1986 to 2001) to determine land cover /use changes. A fairly accuracy report is recorded after performing the unsupervised classification,which shows vegetation has been depleted for over the years. Changes created are mostly human and to a lesser extent environment. Human activities are mainly encroachment thus altering the landscape through activities such as population growth,agriculture,settlements,etc. and environment due to some perceive climatic changes. This vegetation classification highlights the importance to acquire and publish information about the country's partial vegetation cover and vegetation change including vegetation maps and other basic vegetation influencing factors,leading to an understanding of its evolution for a period.
Based on remote sensing technique,using 1990's Landsat TM data and 2000's Landsat ETM data,the authors conducts the comparative study of mainstream area of Songhua River by means of human-computer interaction method. The results show that the area of Songhua River mainstream was 738 102 km2 in 1990, and was 810. 451 km2 in 2000. From 1990 to 2000,the increased area of river mainstream is up to 72. 349 km2 due to soil erosion and water loss. Meanwhile,the dynamic changes of surrounding vegetation cover are also studied. It is estimated that the trend of surrounding soil erosion and water loss of Songhua River mainstream becomes worse in Jilin Province.
Coal bed methane is unconventional raw natural gas stored in coal seam with considerable reserves in China. In recent years,as the coal bed methane production,the safety and the use of resources have been paid more attentions. Evaluating coal bed methane content is an urgent problem. A BET adsorption isotherm equation is used to process the experimental data. The various parameters of BET equation under different temperatures are obtained; a theoretical gas content correction factor is proposed,and an evaluation method of actual coal bed methane is established.
It is difficult for normal moveout ( NMO) correction of shallow long offset of vertical transversely isotropic medium,as seismic event after conventional NMO correction experienced strong stretching and distortion due to interleaving of signal. Even using higher order non-hyperbolic NMO correction,it still cannot get the right results. This paper aims to improve the accuracy of NMO correction. Based on the analysis of conventional NMO correction method and previous optimization move-out equation,we use longitudinal optimization method to correct seismic event. The results of the theoretical model and the real data show that our method can completely remove NMO stretching and greatly improve correction accuracy.
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