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1.
<正>Oil and gas content in shale and mudstone is one of the key factors that influence exploration of shale oil,and how to carry out quantitative study is one of the puzzles to be solved all along.In the last decade,with the progress of exploration practice and improvement of testing method in shale oil,it is possible for researchers to carry out quantitative study on gas content in shale[1-2],and their achievements have widely been applied in shale gas 相似文献
2.
光谱矿物定量方法的基本原理 总被引：2，自引：0，他引：2
On account of the natural distribution of the mineral grains in the specimen under preparation, a new emission-spectrographic method has been developed on the basis of the principles of the permutations and combination of mineral grains, which are deduced from theoretical calculation and experimental tests. This method has been proved valid and applicable to the investigation of .the mode of occurrence of rare elements and to the quantitative determination of minerals as well as to the performance of statistics of their grain -size distribution in geologic samples. 相似文献
3.
Response of Reactive Phosphorus Burial to the Sedimentary Transition from Cretaceous Black Shales to Oceanic Red Beds in Southern Tibet 
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下载免费PDF全文 The mechanism of sedimentary transition from the Cretaceous black shales to the oceanic red beds is a new and important direction of Cretaceous research. Chemical sequential extraction is applied to study the burial records of reactive phosphorus in the black shale of the Gyabula Formation and oceanic red beds of the Chuangde Formation, Southern Tibet. Results indicate that the principal reactive phosphorus species is the authigenic and carbonate-associated phosphorus (CaP) in the Gyabula Formation and iron oxides-associated phosphorus (FeP) in the Chuangde Formation which accounts for more than half of their own total phosphorus content. While the authigenic and carbonate-associated phosphorus (CaP) is almost equal in the two Formations; the iron oxides-associated phosphorus is about 1.6 times higher in the Chuangde Formation than that in the Gyabula Formation resulting in a higher content of the total phosphorus in the Chuangde Formation. According to the observations on the marine phosphorus cycle in Modern Ocean, it is found that preferential burial and regeneration of reactive phosphorus corresponds to highly oxic and reducing conditions, respectively, leading to the different distribution of phosphorus in these two distinct type of marine sediments. It is the redox-sensitive behavior of phosphorus cycle to the different redox conditions in the ocean and the controlling effects of phosphorus to the marine production that stimulate the local sedimentary transition from the Cretaceous black shale to the oceanic red beds. 相似文献
4.
热分析法用于碳酸盐岩石中碳酸盐矿物的定量测定 总被引：2，自引：0，他引：2
Thermal-analysis technique has proved highly effective not only in the qualitative identification of various carbonate minerals in carbonate rocks, but also in the quantitiative determination of them. Both qualitative identification and quantitative determination of carbonate minerals in carbonate rocks can be made based upon the DTA curves produced by various carbonate minerals during their decomposition at different temperatures, and the weight loss of CO2 escaped .from carbonate minerals respectively By comparing the results from artificially prepared sampling tests and the quantitative thermal analysis on Liaoning Sinian carbonate rocks with those from chemical calculation,we can see that the error is as small as below 2.50%. And thus, this technique is considered as one valid method with the advantages of simplibility in performance and reliability in the qualitative identification and quantitative determination of corbonate minerals in carbonate rocks. 相似文献
5.
N.G.Rudraswami A.K.Naik R.P.Tripathi N.BhANDari S.G.Karapurkar M.Shyam Prasad E.V.S.S.K.Babu U.V.R.Vijaya Sarathi 《地学前缘(英文版)》2019,10(2):495-504
The carbonaceous chondrites are intriguing and unique in the sense that they are the only rocks that provide pristine records of the early solar nebular processes. We report here results of a detailed mineralogical, chemical, amino acid and isotopic studies of a recently observed fall at Mukundpura, near Jaipur in Rajasthan, India. Abundance of olivines in this meteorite is low and of serpentine minerals is high. FeO/SiO_2 = 1.05 in its Poorly Characterized Phases(PCP) is similar to that observed in other CM2.0 chondrites. The water content of ～9.8 wt.% is similar to that found in many other CM chondrites.Microscopic examination of matrix shows that its terrestrial weathering grade is WO but aqueous parent body alteration is high, as reflected in low abundance of identifiable chondrules and abundant remnants of chondrules(～7%). Thus, most of the chondrules formed initially have been significantly altered or dissolved by aqueous alterations on their parent bodies. The measured bulk carbon(2.3%) and nitrogen content and their isotopic(δ13C =-5.5‰, δ15N = 23.6%0) composition is consistent with CM2.0 classification probably bordering CM1. Several amino acids such as Alanine, Serine, Proline, Valine, Threonine,Leucine, Isoleucine, Asparagine and Histamine are present. Tyrosine and Tryptophan may occur in trace amounts which could not be precisely determined. All these data show that Mukundpura chondrite lies at the boundary of CM2.0 and CM1 type carbonaceous chondrites making it one of the most primitive chondrites. 相似文献
6.
The experiments on gold solubility in amino acid solution mdicate that gold is very intensively soluble in amino acid(or other organic acids),which is extensively present in geological bodies,and is most soluble in histidine.The temperature and concentration,acidity and type of amino acid in the solution are important factors affecting gold-amino acid complexing. The solubility of gold in amino acid is different under different conditions of temperature, amino acid concentration and pH value of the solution,At 80℃ and pH=6-8,gold is most soluble in amino acid.Gold dispersed in water and rocks could be concentrated and transported by amino acid and then precipitated in favorable loci.Amino acids might have played an important role in metallogenesis as well as in the formation of source beds of gold.Nitrogen,oxygen and sulfur in amino acid might have reacted with gold to form soluble complex ions. 相似文献
7.
He Zhigao 《《地质学报》英文版》1986,60(4):57-65
The compositional variation of oil-soluble gaseous hydrocarbons in high-pressure in-place oil from more than 40 oil wells in the Northern Jiangsu oil field, China, was studied. Samples in which the effects of the factors of pressure and biodegradation had been got rid of were chosen as the representatives that could really reflect the original composition of hydrocarbon gases. Such samples were compared compositionally with their corresponding hydrocarbons formed by decarboxylation of volatile low-molecular fatty acids. Thus highly correlative regularities were found to exist between them. The numerical values of both are graphically expressed. The two curves on the diagram are very similar. These two sets of values have a simple correlation coefficient of 0.9935, which presents their genetic relation.Based on the study of the formation of gaseous hydrocarbons from decarboxylation of volatile fatty acids, the following regularities of the isomers are revealed:1) n-butyric acid + isobutyric acid = propane:2) 1 2 isopentanoic acid(2-methyl-butyric acid) + n-pentanoic acid = n-butane; and3) 1 2 isopentanoic acid(3-methyl-butyric acid) = isobutane.The thermodynamics of decarboxylation was analysed and the enthalpy change △H, entropy change △S and Gibbs free energy change △G in the following reaction were calculated:CH_3COOH(1)--CH_4(g) + CO_2(g).Thus the author considers that the reaction for the formation of hydrocarbons due to the decarboxylation of fatty acids is an exothermic one with increased entropy and decreased free energy as well as a spontaneous one. According to the CRC rule, the resultant Gibbs free energy change △G is approximately-41.84 kJ/mol, which is well within the range of the energy levels of biophysiological changes.According to the changes in odd-carbon preference in n-alkanes of petroleum and sediments and the analysis of fatty acids and amino acids, it is considered that hydrocarbon gases do not originate from pyrolysis or thermal degradation but from decarboxylation of organisms. But this biological reaction is not ordinary biochemical reaction in the artificial fermentation for generating marsh gas. On the basis of the change tendency of the fatty acid content in the fermentation liquor for marsh gas generation and the change tendency of the carbon isotopes in methane and carbon dioxide in the marsh gas, it can be judged that the biochemical reaction for forming hydrocarbon gases is a special biological one occurring after the fermentation. 相似文献
8.
Erum Bashir Shahid Naseem Salma Hamza 《中国地球化学学报》2007,26(3):259-266
Quantitative estimation of ground and stream waters draining through sedimentary rocks of the Pab and Mor ranges (Jurassic-Cretaceous) and the Bela ophiolite has been made. The degree of correspondence among cations and anions has been estimated in order to evaluate their mutual relationships. The abundance of major ions is interpreted to be related to bedrocks and climatic conditions, which may contribute to the genetic affiliation. The log TDS and Na/Na Ca ratio reflected supremacy of weathering of rocks with some influence of evaporation. Ionic relationship is exhibited in the form of Stiff diagrams. Patterns of ionic composition revealed high NaCl, medium Ca(HCO3)2 and low MgSO4. Piper diagram has been used to classify the hydrofacies. The important hydrogeochemical parameters have been estimated for assessment of groundwater quality for domestic purposes in accordance to WHO. Irrigation water qualities have been evaluated in terms of EC, SAR, RSC, ESP and pH. 相似文献
9.
YANG Kai ZHANG Bing WANG Xuben HE Lanfang YANG Hongyu WANG Pengwan TANG Jialin DENG Jixin ZHANG Cong 《《地质学报》英文版》2020,94(5):1531-1546
The Lower Silurian Longmaxi Formation in the south of Sichuan is a key player in the exploration and development of shale gas in China. Due to a highly complex topographic area, electromagnetic methods (EM) become important exploration means in this area. Many studies have been conducted on the shale mineral composition and electrical properties of shale, however, the correlation between sedimentary environments and the electrical properties of shale remain poorly understood. The electrical properties and sedimentary environment of the organic-rich shale of the Longmaxi Formation have been studied by means of X-ray diffraction, organic geochemistry, scanning electron microscopy and complex resistivity measurements. The discovered high quartz content of the Longmaxi Formation shale results in low resistivity. Deep-water shelf biogenic quartz contributes lower resistivity more than that of shallow-water terrigenous quartz. The deep-water anoxic and organic sedimentary environment led to major enrichment of pyrite, leading to a high polarization effect in shale. We present the correlation between the lithofacies types and electrical properties of Longmaxi Formation. The mixed siliceous shale lithofacies is the most favorable among the three lithofacies, which is characterized by high total organic carbon (TOC) content, high brittleness mineral content, high polarization and low resistivity (“three high and one low”). This feature is an effective identification of shale gas reservoirs by electromagnetic prospecting. Our study can provide constraints on electrical parameters of rocks for electromagnetic “sweet spot” exploration of shale gas, and so this has important geological significance to shale gas exploration and development. 相似文献
10.
电子顺磁共振法测定煤、沥青、石油和沉积岩分散有机质中自由基含量及其在地质上的意义 总被引：1，自引：0，他引：1
《地球化学》1975,(1):75-82
Method for determining the radical content in dispersed organic matter from coal, asphalt, petroleum and sedimentary rocks by means of ESR is discussed. Factors affecting the results are also considered. The possibility of using radical content as an indicator is suggested for the degree of metamorphism of the dispersed organic matter and for other geologic problems pertaining to sedimentary rocks and deposits.From the variation of relative concentrations of radical in flame coal samples determined after experiments at elevated temperatures and pressures, the maxium temperature to which the flane coal may have been subjected during its evolution and the temperature-pressure limit for the flame coal-fat coal inversion have been predicted. 相似文献
11.
The origin of the Jurassic low maturity natural gas in the Turpan-Hami Basin has attracted scientists’ attention for some time, and it is known that radiogenesis may have played a role. However, little has been done on the uranium-rich background of the whole basin. Based on plentiful logging and geological data for the Jurassic strata in the Turpan-Hami Basin, this research examined the features and factors controlling the distribution of rocks with high gamma reading. The results show that 70%-100% of the rocks with high gamma readings correspond to mudstones in the prodelta subfacies rather than those in semideep-deep lacustrine subfacies rich in mudstones. Therefore, we propose that the distribution of rocks with high gamma readings is mainly controlled by sedimentary facies rather than by lithology. Further analysis of the gamma spectrometry logging data shows that high gamma values are more strongly correlated with U content than with Th or K content. By comparing the U and Th contents of felsic rocks in peripheral provenances, we find that the Jueluotage Mountain and Harlik Mountain were the dominant uranium sources for the Jurassic Turpan-Hami Basin. Radiolysis due to high-level uranium in the prodelta subfacies can make the low maturity source rocks generate H2 and CH4, thus contributing to the production of low maturity natural gas in the Turpan-Hami Basin. 相似文献
12.
An investigation has been conducted of the geological and geochemical characteristics of euxenitebearing granitic veins found for the first time in China. It is shown that these veins are late intrusives in an Yah Shah granitic complex at a geosyclinal folded zone and composed mainly of medium grained biotite granite in which the local enrichment of euxenite during the late period of magmatic activity is obvious. The mineral has been found to be metamiet and chemically represent a transitional member between euxenite and polyclase. This study has provided a typical example that gralitic melts with a lower initial content of rare elements would contribute significantly to the local enrichment of rare element minerals under special external conditions. 相似文献
13.
SHENG Jun LIU Jincheng LI Yunlong ZOU Haiyan LONG Anlin WANG Lin LI Jiyong QI Qingshan YANG Xiaojing LI Yanan 《《地质学报》英文版》2022,96(3):1070-1081
Cenozoic fine-grained sedimentary rocks in the southwestern Qaidam Basin, as typical salinized lacustrine sediments, are significantly different from those in other freshwater lakes under the impact of the high salinity in the lake. Many fine-grained sedimentary rock samples were selected from the lower member of Neogene (N1) in the Gaskule Oilfield, Qaidam Basin, northwest China, with the aim to analyze and test their petrology, pore structure, and organic geochemical characteristics and determine its genesis and geological significance. Based on previous results, a new genesis of mixed sedimentary rocks is proposed. The Cenozoic lacustrine fine-grained sedimentary rocks in SW Qaidam Basin belong to mixed sedimentary rocks, which can be divided into three types, including carbonate and terrigenous clastic-bearing mudstone, carbonate-bearing to terrigenous clastic mixed sedimentary rocks, and carbonate-terrigenous clastic mixed sedimentary rocks. The geneses of mixing are quite different from that of mixed marine rocks. According to the sedimentary characteristics of the salinized lakes, three new geneses of mixed deposits are proposed: syn-sedimentary mixing, varve interbedded mixing, and biogenic mixing. The reservoir spaces of the Cenozoic lacustrine fine-grained sedimentary rocks in SW Qaidam Basin include residual intergranular pores, intercrystalline pores, microfractures, and minor dissolved pores. The reservoirs have super-low porosity and ultra-low permeability, with a porosity of 1.82%–21.04%, averaging 7.71%, and permeability of (0.0028–254.86) × 10?3 μm2, averaging 2.82 × 10?3 μm2. The test results of total organic carbon (TOC) content show that the highest content of organic carbon reached 1.41%, and those of vitrinite reflectance show that Ro ranges from 0.525%–0.824%, with an average of 0.806%. The organic geochemical characteristics show that the fine-grained mixed sedimentary rocks of SW Qaidam Basin have the potential for self-generation and self-storage. As an unconventional reservoir, it has potential industrial value. This is the first study of fine-grained sedimentary rocks in the Qaidam Basin, which offers certain theoretical and practical values. 相似文献
14.
Treatment with metallic copper for the removal of elemental sulfur from bitumen extracted from sedimentary rocks or petroleum is the most widely used method. Little attention has been paid, however, to its disadvantages. It was observed that copper can interact with some polar organic substances during conventional sulfur removal, which can strongly influence the quantitative and qualitative determination of bitumen, as has been confirmed by interaction of long-chain fatty acids with copper. The copper soap generated was analyzed by element analysis, inductively coupled plasma optical emission spectrometry （ICP-OES）, thermal analysis （TG-DSC） and Fourier Transform Infrared spectroscopy （FFIR）. Mechanism of the interaction was investigated and elucidated. Our experimental results would necessitate improvement of the present method for sulfur removal and/or a search for a new one. 相似文献
15.
Sulfur Isotopic Characteristics of Coal in China and Sulfur Isotopic Fractionation during Coal—burning Process 总被引：5，自引：1，他引：5
The determined results of the sulfur contents and isotopic composition of coal samples from major coal mines in 15 provinces and regions of China show that the coal mined in the north of China is characterized by higher ^34S and lower sulfur content, but that in the south of China has lower ^34S and higher sulfur content.During the coal-burning process in both indrstrial and daily use of coal as fuel the released sulfur dioxide is always enriched in lighter sulfur isotope relative to the corresponding coal;the particles are always enriched in heavier sulfur isotope.The discussion on the environmental geochemical significance of the above-mentioned results also has been made. 相似文献
16.
The Late Precambrian Luoquan Formation occurring on the southern margin of the North China platform is of important significance for the study of the tectonics, palaeogeography, palaeoclimatology and regional stratigraphy of the North China and Yangtze platforms. The origin of diamictites of the formation has long been a subject of controversy. Recently a certain type of cross bedding structure has been recognized in the massive diamictite. Analysis of the process of deposition indicates that the structure was formed by the basal melt-out process of the glacier and, to some extent, its form is the manifestation of the primary structure of basal debris-rich glacial ice. The discovery of this sedimentary structure is inducive to the understanding and reconstruction of the features and environmental conditions for the development of the glaciers in the Luoquan Glacial Epoch. 相似文献
17.
Summing up the abundant experience obtained by the author through many years of his work in mineral separation, an inversion formula has been proposed for calculating the element content in a sample and thus the proportion of minerals containing those elements in the sample. In terms of this inversion formula, the proportion of associated minerals containing the analyzed elements in the sample can be worked out.Long-term practice has proved that if the elcments analyzed quantitatively excees the defined limits, it will be shown that there exist independent minerals in the analyzed sample, and in the opposite case, it may be indicated that there is no presence of such minerals. The element content mainly depends on the type, proportion and grain-size of host minerals. The approach highly sophisticates the traditional method, by which one can not only know the association relations of minerals, but also get sights into the relative proporthin of associated minerals, thus making a very big step in the study of mineral associations from qualitative to quantitative level. 相似文献
18.
To study the quantitative relationship between surface sedimentary diatoms and water depth, 67 surface samples were collected for diatom analysis on eight profiles with water depth variation from the muddy intertidal zone to the shallow sea area in North-Central Bohai Bay, China. The results showed that the distribution of diatoms changed significantly in response to the change in water depth. Furthermore, the quantitative relationship between the distribution of dominant diatom species, their a... 相似文献
19.
Abstract: Deep-water turbidite channels have attracted much attention as a focused issue in petroleum exploration and development. Extensive studies have been performed on the architecture of turbidite channels, and most researches have focused on their geometric shapes, sedimentary processes and controlling factors. However, little attention has been paid to the distribution patterns, distribution laws and quantitative studies of composite sand bodies of turbidite channels. Taken one slope area of the Niger Delta Basin as an example, this study conducted a semi-quantitative to quantitative analysis on architecture of composite sand bodies of turbidite channels based on cores, well logging and seismic surveys. It is shown that turbidite channel systems can be classified as confined and unconfined channel systems. For confined channel systems, the vertical evolution process involves four stages. The sinuosity of a channel system is controlled by slope, with a negative power function relationship between them. When slope gradient reaches four degrees, the channel system is nearly straight. Based on the migration direction and migration amount of single channels within channel complexes, channel composite patterns can be divided into four classes (the lateral composite, en-echelon composite, swing composite and vertical composite) and several subclasses. Various channel composite patterns show specific distribution laws spatially. For meandering channel complexes at the middle-late evolution stage of confined channel systems, the lateral migration amongst single channels shows the features of integrity and succession. The sinuosity of single channels in the late period is greater than that in the early period, and cut-offs may occur locally when the sinuosity is larger than five degrees. This study provides a better understanding for the geological theory of deep-water sedimentary, and also improves exploitation benefits of this type of reservoirs. 相似文献
20.
Zheng M inghu Zhou Yufeng Fu Reaping Department of Mineral Resources Chengdu University of Technology Chengdu Sichuan Fei Zhenbi 《《地质学报》英文版》1995,69(4)
In recent years, a considerable amount of microscopic spherules have been found in concentrates recovered from some stratabound gold deposits occurring in Middle-Upper Triassic turbidite series in northwestern Sichuan. Study indicates that these spherules are cosmic dust. It is the first time that cosmic dust of extraterrestrial origin has been found in hydrothermal gold deposits in China.The spherules are steel-grey in colour and show metallic luster. Their grain size is commonly less than 100 μm. According to their composition, they belong to chromium-rich iron cosmic dust. The spherules have complex and diverse microscopic structures and textures, i.e. they show a very distinct Widmanstaten structure.The variation of cosmic dust content in gold deposits exhibits a positive correlation with the mineralization intensities and hydrothermal alteration. Such a relation indicates that the ore sub- stances may transport not only mechanically but also may chemically in hydrothermal solutions. 相似文献