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1.
The French Society of Mineralogy and Crystallography is honoured to be invited to give a short presentation of its activity to the Chinese Society for Mineralogy,Petrology and Geochemistry.BRIEF HISTORY AND SOME FRENCH FOUNDERS OF MINERALOGY  相似文献   

2.
The hydroxyl in phyllosilicate minerals is the most common occurrence of water in primitive meteorites. Direct hydrogen isotopic analysis of this water component using an ion microprobe has been made in some glassy or phyllosilicate spherules from the Al Rais (CR) and Orgueil (CI) chondrites. The spherules from Al Rais show large deuterium excesses (δD = +200 -+800‰) relative to terrestrial standards, whereas deuterium-enrichments in the spherules from Orgueil are much smaller (δD = +40 - +130‰). The phyllosilicate spherules are products of  相似文献   

3.
ＱＵＡＮＴＩＴＡＴＩＶＥＤＹＮＡＭＩＣＳＴＲＡＴＩＧＲＡＰＨＹ（ＱＤＳ）Ｄｕｒｉｎｇｔｈｅｐａｓｔｆｅｗｄｅｃａｄｅｓｉｎｄｅｐｅｎｄｅｎｔｓｔｕｄｉｅｓｏｆｓｅｄｉ－ｍｅｎｔａｒｙｂａｓｉｎｓｗｅｒｅｃａｒｒｉｅｄｏｕｔａｌｏｎｇｄｉｆｅｒｅｎｔａ...  相似文献   

4.
Vibrational properties of diaspore, α-AlOOH, have been re-investigated using room-temperature single-crystal Raman spectroscopy and low-temperature powder infrared (IR) transmission spectroscopy. First-principles harmonic calculations based on density functional theory provide a convincing assignment of the major Raman peaks and infrared absorption bands. The large width of the Raman band related to OH stretching modes is ascribed to mode–mode anharmonic coupling due to medium-strength H-bonding. Additional broadening in the powder IR spectrum arises from depolarization effects in powder particles. The temperature dependence of the IR spectrum provides a further insight into the anharmonic properties of diaspore. Based on their frequency and temperature behavior, narrow absorption features at ~2,000 cm−1 and anti-resonance at ~2,966 cm−1 in the IR spectrum are interpreted as overtones of fundamental bending bands.  相似文献   

5.
ＰＯＳＩＮＧＴＨＥＰＲＯＢＬＥＭ“ＣｏｍｐｌｅｘｉｔｙａｎｄＳｅｌｆ－ＯｒｇａｎｉｚｅｄＣｒｉｔｉｃａｌｉｔｙｏｆＳｏｌｉｄＥａｒｔｈＳｙｓｔｅｍ”ｉｓａｎｅｗｐｒｏｂｌｅｍａｓｗｅｌａｓａｎｅｗｐｒｏｐｏｓｉｔｉｏｎ．Ｔｈｅａｕｔｈｏｒｐｕｔｓｆｏ...  相似文献   

6.
The biogeochemical migration of iodine in soil and its effect factors were studied by the isotope tracer (125I) and experiments of leaching and absorption by Chinese cabbage to iodine under simulated condition. The results show that the quantities of tran…  相似文献   

7.
The Lisan Peninsula is located within the Dead Sea basin which represents the plate boundary between African and Arabian plates. This basin constitutes a good example of a pull-apart basin because of its large dimensions, its structural simplicity and its active subsidence . The gravity data reveal that the Dead Sea basin can be divided into segments, each of them about 30 km long in N-S direction , where the Lisan Peninsula represents the deepest one (9 km thick Pleistocene sediments ), overlying about 6 km thick Mesozoic sediments . In addition , 20 km of extension was predicted along the Dead Sea basin, which indicates that the Dead Sea basin should be about 3.3 Ma in age . Furthermore, the Precambrian basement under the Lisan area is characterized by high susceptibility contrast that is related to continuous tectonic activity in the region.  相似文献   

8.
Earth-reservoirs are increasingly exploited today with the extraction of resources, such as heat and hydrocarbons, and the large-scale emplacement of waste, such as CO2 sequestration. The characterization, site investigation, predictive modeling and long-term monitoring are dependent on the processes being investigated and modeled. In most cases complex coupled processes have to be addressed in a geologically complex rock mass system. In this paper we present a conceptual holistic framework known as geomechanical facies linking all the scales of investigation, characterization and reservoir development methods. We demonstrate this concept on the work undertaken during the design and development of the enhanced geothermal systems (EGS) systems at the forefront of European Hot-Dry-Rock (HDR) technology, Soultz-sous-Forêts (France) and Spa Urach (Germany). Soultz-sous-Forêts is situated within granitic rocks and an active tectonic graben system in the central part of the Rhine Graben. It presents conditions of lithology, temperature, stress, hydraulics and geochemistry that are very different from those at Spa Urach, located in a very dense gneiss formation in the South German crystalline complex. Spa Urach exhibits more elastic behavior and is set tectonically within an almost inactive strike-slip stress field described in more detail in Sects. “Drill core analysis” and “Hydraulic stimulation at Spa Urach”. This paper compares the exploration and field development methods used at these two sites against the back drop of the geomechanical facies concept. Issues addressed include the key parameters for flow and heat transport properties, coupled hydro-mechanical process identification, the success of the HDR reservoir as a heat exchanger and exploration techniques applicable to the different facies. Identification of the key geomechanical facies gives an indication as to which technologies will prove more efficient in the application of HDR technology. The results of this study will hopefully help in developing heat recovery schemes for the long-term economical operation of future HDR plants and EGS as well as assist in the understanding of engineered geosystems.  相似文献   

9.
An almost complete juvenile dinosaur skull with lower jaw was discovered from the Early Cretaceous Yixian Formation in Beipiao, Liaoning Province, China. Here, the specimen is described and a cladistic analysis is performed in order to find its phylogenetic relationships. The result shows that this specimen represents a new genus of Psittacosauridae, Hongshanosaurus houi, gen. et sp. nov., and confirms the monophyletic status for Ceratopsia and Marginocephalia. However, Heterodontosaurus is found to be the sister taxon to Marginocephalia, rather than a basal Omithopoda.  相似文献   

10.
Sedimentary indicators of catastrophic glacial megafloods—plane-bedded angular gravel, cobbles, and boulders—are described in several sections of the high terraces of the Chuya River valley. The principal difference of these sediments from typical alluvium of this area is demonstrated. The clast roundness, grain size of clasts, and sedimentary structures of the high-terrace deposits of the Chuya and Katun’ valleys indicate the same facies originated through megaflood deposition. These results are at odds with ideas of alluvial, glacial, or glaciofluvial genesis of the high-terrace deposits of the Chuya River.  相似文献   

11.
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12.
Batch adsorption and dissolution experiments with lepidocrocite (γ-FeOOH) and two siderophores, desferrioxamine B (DFOB) and aerobactin, were performed between pH 3 and 8 in the dark and under irradiation with UV-visible light. The increase in surface concentrations of adsorbed DFOB with increasing pH was explained in terms of electrostatic interactions between the protonated and charged terminal amine group of DFOB surface complexes and the charged lepidocrocite surface. The adsorption of aerobactin was consistent with the typical anion-like adsorption behavior of low molecular weight organic acids and indicated that the adsorption properties are strongly determined by the carboxylic acid groups. The adsorption experiments revealed furthermore that the Fe(III)-DFOB solution complex has a very low affinity for the surface, in contrast to Fe(III)-aerobactin solution complexes. In accordance with a surface-controlled mechanism of ligand-promoted dissolution, we found a linear correlation between dissolution rates of lepidocrocite and the surface concentrations of adsorbed DFOB. In the dark, 6- to 8-fold lower dissolution rate coefficients were determined for aerobactin in comparison to DFOB. These results suggested that aerobactin forms surface complexes that are less dissolution-active, characterized by a higher degree of multinuclear surface complexation and/or by less dissolution-active coordination modes of the involved iron-binding groups. For both DFOB and aerobactin, dissolution rate coefficients increased significantly under irradiation with UV-visible light. This increase was interpreted in terms of light-induced reduction of surface Fe(III), primarily by intrinsic photochemical processes of the lepidocrocite bulk phase, based on the observed photoreductive dissolution in the absence of organic ligands between pH 3 and 6. We hypothesize that the α-hydroxycarboxylate group of aerobactin may form a surface complex that additionally promotes photoreductive dissolution by a ligand-to-metal charge-transfer (LMCT) reaction, similar to citrate. However, LMCT reactions involving the α-hydroxycarboxylate group of aerobactin are rather ineffective, based on the comparison of light-induced dissolution rate coefficients determined in the presence of aerobactin and citrate.  相似文献   

13.
The compressibility of -Mns (alabandite) was determined by x-ray analysis using a Mao-Bell type diamond anvil cell. The zero pressure bulk modulus (K0) is 74±2 GPa with the pressure derivative of the bulk modulus (Ko) fixed at four. Allowing (Ko) to vary yielded a statistically better fit with K0 = 88±6 GPa and k0 = 2.2±0.6. Our data combined with the data of McCammon (1991) gave Ko = 73±1 GPa with ko fixed at four. A fit with ko allowed to vary yielded ko = 75±2 GPa and ko = 3.7±0.4. Alabandite transformed from the B1 structure (NaCl-type) to an unknown high-pressure phase at 26 GPa. The high-pressure phase has lower than hexagonal symmetry and it is stable to at least 46±4 GPa.Also affiliated with the James Franck Institute, University of Chicago  相似文献   

14.
The F–(Ba–Pb–Zn) ore deposits of the Zaghouan District, located in NE Tunisia, occur as open space fillings or stratabound orebodies, hosted in Jurassic, Cretaceous and Tertiary layers. The chondrite-normalized rare earth element (REE) patterns may be split into three groups: (i) “Normal marine” patterns characterizing the wallrock carbonates; (ii) light REE (LREE) enriched (slide-shaped) patterns with respect to heavy REE (HREE), with small negative Ce and Eu anomalies, characteristic of the early ore stages; (iii) Bell-shaped REE patterns displaying LREE depletion, as well as weak negative Ce and Eu anomalies, characterizing residual fluids of subsequent stages. The 87Sr/86Sr ratios (0.707654–0.708127 ± 8), show that the Sr of the epigenetic carbonates (dolomite, calcite) and ore minerals (fluorite, celestite) are more radiogenic than those of the country (Triassic, Jurassic, Cretaceous, lower Miocene) sedimentary rocks. The uniformity of this ratio, throughout the District, provides evidence for the isotopic homogeneity and, consequently, the identity of the source of the mineralizing fluids. This signature strongly suggests that the radiogenic Sr is carried by Upper Paleozoic basinal fluids.The δ34S values of barite, associated to mineralizations, are close to those of the Triassic sea water (17‰). The δ34S values of sulfide minerals range from − 13.6‰ to + 11.4‰, suggesting two sulfur-reduced end members (BSR/TSR) with a dominant BSR process.Taking account of the homogeneity in the Pb-isotope composition of galenas (18.833–18.954 ± 0.001, 15.679–15.700 ± 0.001 and 38.690–38.880 ± 0.004, for the 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios respectively), a single upper crustal source for base-metals is accepted. The Late Paleozoic basement seems to be the more plausible source for F–Pb–Zn concentrated in the deposits. The genesis of the Zaghouan District ore deposits is considered as the result of the Zaghouan Fault reactivation during the Late Miocene period.  相似文献   

15.
Platinum-group elements （PGE） in PGE-rich porphyry copper （gold） deposits are mainly Pt and Pd, whereas the concentrations of other PGE （Ru, Rh, Os, Ir） are significantly low. Moreover, Pt and Pd mainly exist in sulfides in the forms of crystal lattice or tiny platinum-group mineral （PGM） inclusions. The present data show that there is a positive relationship between Pt and Pd concentrations and Cu （Au） in porphyry copper （gold） deposits. The comparison of chondrite-normalized PGE distribution patterns between the ore-bearing porphyry intrusions and ore-barren porphyry intrusions in arc setting, 187^Os/188^Os, 87^Sr/86^Sr and S isotopes for porphyry copper （gold） deposits shows that PGEs were mainly derived from the mantle, and fluids from subduction zones devoted trivial PGE to the magma. The porphyry copper （gold） deposits associated with subducted events are most probably enriched in PGE, whereas those related to crustal thickening, lithospheric delamination or underplating rarely concentrate PGE. The osmium isotopic compositions in porphyry copper （gold） deposits reveal that （187^Os/188^Os）i values are highly variable and not lower than those of primitive upper mantle （PUM） and mantle peridotite, however, osmium concentrations are commonly lower than mantle peridotite, suggesting that parental magmas of some porphyry intrusions had experienced crustal contamination during magma evolution. Experimental investigations have proved that PGE exist in the forms of Cl^- and HS^- complexes during transportation and migration of the oreforming fluids. This paper summarizes previous studies including crucial controlling factors and mechanisms for PGE enrichment, and points out that the mantle-derived magmas parental to porphyry intrusions are the prerequisite for PGE enrichment in porphyry copper （gold） deposits. Favorable physical and chemical conditions （including salinity, temperature, pressure, pH, and oxygen fugacity） in hydrothermal fluids crucially control the  相似文献   

16.
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17.
The study provides new petrologic and isotope geochemical data for rocks of the 465 ± 5 Ma Bulka massif (Borodina et al., 2011). The primary amphibole from granitoid stocks cutting across the layered series of the massif yielded an Ar–Ar age of 415.9 ± 3.7 Ma. The rocks of the Bulka massif have 143Nd/144Nd ratio of 0.513243 and εNd (Т) values of +12.00. The granitoids have 143Nd/144Nd ratios between 0.512919 and 0.512961 and εNd (Т) values between +8.03 and +9.25. The Nd isotope composition indicates that the rocks of the Bulka massif and granitoids were derived from a depleted mantle source. Depletion of the rocks of the massif in LILE, LREE, and HFSE over LILE is inherited from the mantle source, which has geochemical signatures of N-MORB and subduction-related components. Granitoids are metaluminous I-type granites, which were probably generated either by differentiation of intermediate to mafic mantle-derived magmas or by melting of metabasites. The rocks of the granitoid stocks are characterized by enrichment in LILE and LREE and depletion in HFSE over LILE, which suggests derivation from arc-related parental magmas.  相似文献   

18.
There are several source rock units in the Zagros Basin, but the Cretaceous Kazhdumi and Paleogene Pabdeh formations probably have produced the majority of the commercial hydrocarbons in this area. Among the hydrocarbon provinces of Iran, the Dezful Embayment, which is located southwest of Zagros Mountains, is one of the most prolific regions in the Middle East. Numerous studies have been made in the northern part of the Dezful Embayment, but relatively few have been done in its southern part. The present study focuses on organic matter characterization of two potential source rocks (Kazhdumi and Pabdeh formations) in southern part of the Dezful Embayment. Cuttings samples (114) were collected from 10 wells and evaluated using Rock–Eval pyrolysis and organic petrography in order to characterize the content and type of organic matter and thermal maturity. The results showed that the average total organic carbon (TOC) content of Kazhdumi and Pabdeh formations are 2.48 and 1.62 wt%, respectively. The highest TOC contents for both formations are found in the northern compartment and decreased gradually toward the south. Pyrolysis data reveal that organic matter has a fair to very good hydrocarbon generation potential and are classified as Type II–III and Type III. Rock–Eval Tmax and vitrinite reflectance show that the majority of samples are in the early mature to mature stage of the oil generation window.  相似文献   

19.
Magneticmineralsintheloess paleosolseriesaccountforabout 1 % -2 %ofthetotal (LiuTungshengandZhangZhonghu ,1 962 ) .Duetotheiraerolianorigin ,themagneticmineralsarecomplicatedincomposition ,largeingrainsizerange ,andsignificantlydifferentincrystallinity .Asaresult,researchonthesemagneticmineralswouldbesetwithalotofdifficulties.Previousre searchersemployedopticalmicroscopic ,X raydiffractionandM ssbauerspectrometrictechniquestostudythemagneticmineralsintheloess paleosolseries,andchieflyontheb…  相似文献   

20.
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