Yangtze- and Taiwan-derived sediments on the inner shelf of East China Sea

X-ray diffraction (XRD) mineralogical and grain-size analyses indicate that inner continental shelf sediments in the East China Sea (ECS) represent a unique mixing of clays derived from the Yangtze River and silts/sands from small western Taiwanese rivers. Taiwanese (e g., Choshui) clays (< 2 mu m) display no smectite but the best illite crystallinity and are only distributed along southeastern Taiwan Strait. Both Yangtze and Taiwanese river clays are illite-dominated, but the poor illite crystallinity and the presence of smectite and kaolinite indicate that Taiwan Strait clays are mainly Yangtze-dominated. In contrast, medium silts (20-35 mu m) and very fine sands (63-90 mu m) in the Taiwan Strait are characterized by low feldspar/quartz, low K-feldspar/plagioclase and high kaolinite/quartz, indicating their provenance from Taiwanese rivers. Taiwanese silts and sands are introduced primarily by the way of typhoon-derived floods and transported northward by the Taiwan Warm Current during summer-fall months. Yangtze clays, in contrast, are widely dispersed southward about 1000 km to the western Taiwan Strait, transported by the China Coastal Current during winter-spring months Since most Taiwan Strait samples were collected in May 2006, clay results in this paper might only represent the winter-spring pattern of the dispersal of Yangtze sediments. (C) 2009 Elsevier Ltd. All rights reserved.

REE and epsilon(Nd) of clay fractions in sediments from the eastern Pacific Ocean: Evidence for clay sources

Clay fractions in the non-calcareous surface sediments from the eastern Pacific were analyzed for clay minerals, REE and Nd-143/Nd-144. Montmorillonite/illite ratio (M/I ratio), total REE contents (Sigma REE), LREE/HREE ratio and cerium anomaly (delta Ce) may effectively indicate the genesis of clay minerals. Clay fractions with M/I ratio > 1, delta Ce < 0.85, Sigma REE > 400 mu g/g, LREE/HREE ratio approximate to 4, and REE patterns similar to those of pelagic sediments are terrigenous and autogenetic mixed clay fractions and contain more autogenetic montmorillonite. Clay fractions with M/I ratio < 1, delta Ce=0.86 to 1.5, Sigma REE=200 to 350 mu g/g, LREE/HREE ratio approximate to 6 and REE distribution patterns similar to that of China loess are identified as terrigenous clay fraction. The Nd-143/Nd-144 ratios or epsilon(Nd) values of clay fractions inherit the features of terrigenous sources of clay minerals. Clay fractions are divided into 4 types according to epsilon(Nd) values. Terrigenous clay minerals of type I with the eNd values of -8 to -6 originate mainly from North American fluvial deposits. Those of type 11 with the epsilon(Nd) Values of -9 to -7 are mainly from the East Asia and North American fluvial deposits. Those of type III with epsilon(Nd) values of -6 to -3 could come from the central and eastern Pacific volcanic islands. Those of type IV with epsilon(Nd) values of -13 to -12 may be from East Asia eolian. The terrigenous and autogenetic mixed clay fractions show patchy distributions, indicating that there are volcanic or hot-spot activities in the eastern Pacific plate, while the terrigenous clay fractions cover a large part of the study area, proving that the terrigenous clay minerals are dominant in the eastern Pacific.

Clay mineral distributions in the southern Yellow Sea and their significance

To better understand the characteristics of the clay minerals in the southern Yellow Sea, the X-ray quantitative determinations have been carried out for the surface samples obtained from the Yellow Sea. With newly compiled clay mineral synoptic maps, the depositional processes were described for four main clay minerals (illite, chlorite, kaolinite and smectite). The analysis shows that most clay minerals are of terrigenous source with the Huanghe River acting as the major sediment supplier. Besides, the source of muddy sediments in the Yellow Sea was also discussed. As for the central Yellow Sea mud (CYSM), the sediments in its northern part mainly come from the Huanghe River, and those in the rest are of multi-origin. Very similarly, a large amount of sediments in the northern part of the southeastern Yellow Sea Mud (SEYSM) derive from the Keum River and Yeong-san River, while those in the southern part are of multi-origin.

Development of the East Asian monsoon: Mineralogical and sedimentologic records in the northern South China Sea since 20 Ma

We here reconstruct the past change of the East Asian monsoon since 20 Ma using samples from Ocean Drilling Program (ODP) Site 1146 in the northern South China Sea based On a multi-proxy approach including a monomineralic quartz isolation procedure, identification of clay minerals by X-ray Diffraction (XRD) and grain-size analysis of isolated terrigenous materials. Terrigenous supply to ODP Site 1146 was dominated by changes in the strength of multiple sources and transport processes. Grain-size data modeled by an end-member modeling algorithm indicate that eolian dust from the and Asian inland and fluvial input have contributed on average 20% and 80% of total terrigenous material to ODP Site 1146, respectively. Specifically, about 40-53% of the total (quartz+feldspar) and only 6-11% of the total clay is related to eolian supply at the study site. Detailed analysis of the sedimentary environment, and clay minerals combined with previous studies shows that smectite originates mainly from Luzon, kaolinite from the Pearl River and illite and chlorite from the Pearl River, Taiwan and/or the Yangtze River. The proportion and mass accumulation rate (MAR) of the coarsest end-member EM1 (interpreted as eolian dust), ratios of (illite+chlorite)/smectite, (quartz+feldspar)% and mean grain-size of terrigenous materials at ODP Site 1146 were adopted as proxies for East Asian monsoon evolution. The consistent variation of these independent proxies since 20 Ma shows three profound shifts in the intensity of East Asian winter monsoon relative to summer monsoon, as well as aridity of the Asian continent, occurred at similar to 15 Ma, similar to 8 Ma and the youngest at about 3 Ma. In comparison, the summer monsoon intensified contemporaneously with the winter monsoon at 3 Ma. The phased uplift of the Himalaya-Tibetan plateau may have played a significant role in strengthening the Asian monsoon at similar to 15 Ma, 8 Ma and 3 Ma. (C) 2007 Elsevier B.V. All rights reserved.

Evolution and variability of the East Asian summer monsoon during the Pliocene: Evidence from clay mineral records of the South China Sea

The Late Pliocene is thought to be characterized by the simultaneous intensification of both the East Asian winter monsoon (EAWM) and East Asian summer monsoon (EASM). However, the evolution of the EASM during the Pliocene remains still controversial and only little is known about the dynamics of the EASM during the Pliocene on orbital time scales. Here we use clay mineral assemblages in sediments from Ocean Drilling Program (ODP) Site 1143 in the southern South China Sea (SCS) to obtain proxy records of past changes in the EASM climate during the Pliocene. Provenance analysis suggests that illite, chlorite and kaolinite originated mainly from the Mekong River drainage area. Smectite was derived mainly from the Indonesian islands. The kaolinite/illite ratio and the chemical index of alteration (CIA) of siliciclastic sediments allowed us to reconstruct the history of chemical weathering and physical erosion of the Mekong River drainage area and thus, the evolution of,the EASM during the Pliocene. Our clay minerals proxy data suggests a stronger EASM during the Early Pliocene than during the Late Pliocene. We propose that the long-term evolution of the EASM has been driven by global cooling rather than the uplift of the Tibetan Plateau. Spectral analysis of kaolinite/ illite ratio displays a set of strong periodicities at 100 ka, 30 ka, 28 ka, 25 ka, and 22 ka. with no clear obliquityrelated signal. Our study suggests that the Pliocene EASM intensity on orbital time scales is not only controlled by the Northern Hemisphere summer insolation, but also strongly influenced by equatorial Pacific ENSO-like ocean atmosphere dynamics. (C) 2010 Elsevier B.V. All rights reserved.

Characteristics of clay minerals in the northern South China Sea and its implications for evolution of East Asian monsoon since Miocene

Clay mineral assemblages, crystallinity, chemistry, and micromorphology of clay particles in sediments from ODP Site 1146 in the northern South China Sea (SCS) were analyzed, and used to trace sediment sources and obtain proxy records of the past changes in the East Asian monsoon climate since the Miocene, based on a multi-approach, including X-ray diffraction (XRD) and scanning electron microscopy combined with energy dispersive X-ray spectrometry (SEM-EDS). Clay minerals consist mainly of illite and smectite, with associated chlorite and kaolinite. The illite at ODP Site 1146 has very well-to-well crystallinity, and smectite has moderate-to-poor crystallinity. In SEM the smectite particles at ODP Site 1146 often appear cauliflower-like, a typical micromorphology of volcanic smecites. The smectite at ODP Site 1146 is relatively rich in Si element, but poor in Fe, very similar to the smectite from the West Philippine Sea. In contrast, the chemical composition of illite at ODP Site 1146 has no obvious differences from those of the Loess plateau, Yellow River, Yangtze River, and Pearl River. A further study on sediment source indicates that smectite originates mainly from Luzon, kaolinite from the Pearl River, and illite and chlorite from the Pearl River, Taiwan and/or the Yangtze River. The clay mineral assemblages at ODP Site 1146 were not only controlled by continental eathering regimes surrounding the SCS, but also by the changing strength of the transport processes. The ratios of (illite+chlorite)/smectite at ODP Site 1146 were adopted as proxies for the East Asian monsoon evolution. Relatively higher ratios reflect strongly intensified winter monsoon relative to summer monsoon, in contrast, lower ratios indicate a strengthened summer monsoon relative to winter monsoon. The consistent variation of this clay proxy from those of Loess plateau, eolian deposition in the North Pacific, planktonic, benthic foraminifera, and black carbon in the SCS since 20 Ma shows that three profound shifts of the East Asian winter monsoon intensity, and aridity in the Asian inland and the intensity of winter monsoon relative to summer monsoon, occurred at about 15 Ma, 8 Ma, and the younger at about 3 Ma. The phased uplift of the Himalaya-Tibetan plateau may have played a significant role in strengthening the Asian monsoon at 15 Ma, 8 Ma, and 3 Ma.

班公湖带多不杂超大型富金斑岩铜矿床的成岩成矿年代学、岩石学及高氧化岩浆¬流体-成矿作用

Duobuza copper deposit, newly discovered typical gold-rich porphyry copper deposit with superlarge potential, is located in the Tiegelong Mesozoic tectonic -magmatic arc of the southern edge of Qiangtang block and the northern margin of Bangonghu-Nujiang suture. Quartz diorite porphyrite and grandiorite porphyry, occurred in stock, are the main ore-bearing porphyries. As the emplacement of porphyry stock, a wide range of hydrothermal alteration has developed. Within the framework of the ore district, abundant hydrothermal magnetite developed, and the relationship between precipitation of copper and gold and hydrothermal magnetite seems much close. Correspondingly, a series of veinlets and network veinlets occurred in all alteration zones. Therefore, systematic research on such a superlarge high-grade Duobuza gold-rich porphyry copper deposit can fully revealed the metallogenic characteristics of gold-rich porphyry copper deposits in this region, establish metallogenetic model and prospecting criteria, and has important practical significance on the promotion of regional exploration. In addition, this research on it can enrich metallogenic theory of strong oxidation magma-fluid to gold-rich porphyry copper deposit, and will be helpful to understand the metallogenic characteristics in early of subduction of Gangdese arc stages and its entire evolution history of the Qinghai-Tibet Plateau, the temporal and spatial distribution of ore deposits and their geodynamics settings. Northern ore body of Duobuza copper deposit have been controlled with width (north-south) about 100 ~ 400 m, length (east-west) about 1400 m, dip of 200 °, angle of dip 65 °~ 80 °. And controlled resource amount is of 2.7 million tons Cu with grade 0.94% and 13 tons Au with 0.21g/tAu. Overall features of ore body are large scale, higher grade copper, gold-rich. Ore occurred in the body of granodiotite porphyry and quartz diorite porphyrite and its contact zone with wall rock. Through the detailed mapping and field work studies, some typies of alteration are identificated as follows: albitization, biotititation, sericitization, silication, epidotization, chloritization, carbonatization, illitization, kaolinization and so on. The range of alteration is more than 10km2. Wall alteration zone can be divided into potassic alteration, moderate argillization alteration, argillization, illite-hydromuscovite or propylitization from ore-bearing porphyry center outwards, but phyllic alteration has not well developed and only sericite-quartz veins occurred in local area. Moreover, micro-fracture is development in ore district , and correspondingly a series of veinlets are development as follows: biotite vein (EB type), K-feldspar-biotite-chalcopyrite-quartz vein, magnetite-antinolite-K-feldspar vein, quartz-chalcopyrite-magnetite veins (A-type), quartz-magnetite-biotite-K-feldspar vein, chalcopyrite veinlets in potassic alteration zone; (2) chalcopyrite occurring in the center vein–quartz vein (B type), chalcopyrite veinlets, chalcopyrite-gypsum vein in intermediate argillization alteration; (3) chalcopyrite- pyrite-quartz vein, pyrite-quartz vein, chalcopyrite-gypsum veins, quartz-gypsum- molybdenite-chalcopyrite vein in argillization alteration; (4) gypsum veins, quartz-(molybdenite)-chalcopyrite vein, quartz-pyrite vein, gypsum- chalcopyrite vein, potassium feldspar veinlets, Carbonate veins, quartz-magnetite veins in the wall rock. In short, various veins are very abundant within the framework of the ore district. The results of electronic probe microscopy analysis (EMPA) indicate that Albite (Ab 91.5~99.7%) occurred along the rim of plagioclase phenocryst and fracture, and respresents the earliest stages of alteration. K-feldspar (Or 75.1~96.9%) altered plagioclase phenocryst and matrix or formed secondary potassium feldspar veinlets. Secondary biotite occurred mainly in phenocryst, matrix and veinlets, belong to magnesium-rich biotite formed under the conditions of high-oxidation magma- hydrothermal. Chloritization developed in all alteration zones and alterd iron- magnesium minerals such as biotite and hornblende and then formed chlorite veinlets. As the temperature rises, Si in the tetrahedral site of chlorite decreased, and chlorite component evolved from diabantite to ripiolite. The consistent 280℃~360℃ of formation temperature hinted that chlorite formed on the same temperature range in all alteration zones. However, formation temperature range of chlorite from the gypsum-carbonate-chlorite vein was 190℃~220℃, and it may be the product of the latest stage of hydrothermal activity. The closely relationship between biotite and rutile indicate that most of rutiles are precipitated in the process of biotite alteration and recrystallization. In addition, the V2O3 concentration of rutile from ore body in Duobuza gold-rich porphyry copper deposit is >0.4％, indicate that V concentration in rutile has important significance on marking main ore body of porphyry copper deposit. Apatites from Duobuza deposit all are F-rich. And apatite in the wall rock contained low MnO content and relatively high FeO content, which may due to the basaltic composition of the wall rocks. The MnO in apatite from altered porphyry show a strong positive correlation with FeO. In addition, Cl/F ratio of apatite from wall rock was highest, followed by the potassic alteration zone and potassic alteration zone overprinted by moderate argillization alteration was the lowest. SO2 in Apatite are in the scope of 0 to 0.66%, biotite in the apatite has the highest SO2, followed by the potassic alteration zone, potassic alteration zone overprinted by moderate argillization alteration, and the lowest in the surrounding rocks, which may be caused by the decrease of oxygen fugacity of hydrothermal fluid and S exhaust by sulfide precipitation in potassic alteration. Magnetite in the wall rock have higher Cr2O3 and lower Al2O3 features compared with altered porphyry, this may be due to basalt wall rock generally has high Cr content. And magnetites have higher TiO2 content in potassic alteration than moderate argillization alteration overprinted by potassic alteration, argillization and wall rock, suggested that its formation temperature in potassic alteration was the highest among them. The ore minerals mainly are chalcopyrite and bornite, and Au contents of chalcopyrite, bornite, and pyrite are similar with chalcopyrite slightly higher. The Eu* negative anomaly of disseminated chalcopyrite was relatively lower than chalcopyrite in veinlets. Within a drill hole, the Eu* negative anomaly of disseminated chalcopyrite was gradually larger from bottom to top. Magnetite has the same distribution model, with obvious negative Eu* abnormal, and ΣREE in great changes. The gypsum has the highest ΣREE content and the obvious negative anomaly, and biotite obviously has the Eu* abnormal. Based on the petrographic and geochemical characteristics, five series of magmatic rocks can be broadly classified; they are volcanic rocks of the normal island arc, high-Nb basaltic rocks, adakites, altered porphyry and diorite. The Sr, Nd, Hf isotopes and geochemistry of various series of magmatic rock show that they may be the result of mixing between basic magma and various degrees of acid magma coming from lower crust melted by high temperature basic underplating from partial melting of the subduction sediment melt metasomatic mantle wedge. Furthermore S isotope and Pb isotope of the sulfide, ore-bearing porphyries and volcanic rocks indicated ore-forming source is the mantle wedge metasomatied by subduction sediment melt. Oxygen fugacity of magma estimated by Fe2O3/FeO of whole rock and zircon Ce4+/Ce3+ indicated that the oxidation of basalt-andesitic rocks is higher than ore-forming porphyry, and might imply high-oxidation characteristics of underplated basic magma. Its high oxidative mechanism is likely mantle sources metasomatied by subduction sediment magma, including water and Fe3+. And such high oxidation of basaltic magma is conducive to the mantle of sulfides in the effective access to melt. And the An component of dark part within plagioclase phenocryst zoning belong to bytownite (An 74%), and its may be a result of magma composition changes refreshment by basaltic magma injection. SHRIMP zircon U-Pb and LA-ICP-MS zircon U-Pb geochronology study showed that the intrusions and volcanic rocks from Duobuza porphyry copper deposit belong to early Cretaceous magma series (126~105Ma). The magma evolution series are as follows: the earliest diorite and diorite porphyrite → ore-bearing porphyry and barren grandiorite porphyry →basaltic andesite → diorite porphyrite → andesite → basaltic andesite, and magma component shows a evolution trend from intermediate to intermediate-acid to basic. Based on the field evidences, the formation age of high-Nb basalt may be the latest. The Ar-Ar geochronology of altered secondary biotite, K-feldspar and sericite shows that the main mineralization lasting a interval of about 4 Ma, the duration limit of whole magma-hydrothermal evolution of about 6 Ma, and possibly such a long duration limit may result in the formation of Duobuza super-large copper deposit. Moreover, tectonic diagram and trace element geochemistry of volcanic rocks and diorite from Duobuza porphyry copper deposit confirm that it formed in a continental margin arc environment. Zircon U-Pb age of volcanic rocks and porphyry fall in the range of 105~121Ma, and Duobuza porphyry copper deposit locating in the north of the Bangonghu- Nujiang suture zone, suggested that Neo-Tethys ocean still subducted northward at least early Cretaceous, and its closure time should be later than 105 Ma. Three major inclusion types and ten subtypes are distinguished from quartz phenocrysts and various quartz veins. Vapor generally coexisting with brine inclusions, suggest that fluid boiling may be the main ore-forming mechanism. Raman spectrums of fluid inclusions display that the content of vapor and liquid inclusion mainly contain water, and vapor occasionally contain a little CO2. In addition, the component of liquid inclusions mainly include Cl-, SO42-, Na+, K+, a small amount of Ca2+, F-; and Cl- and Na+ show good correlation. Vapor mainly contains water, a small amount of CO2, CH4 and C2H6 and so on. The daughter minerals identified by Laman spectroscopy and SEM include gypsum, chalcopyrite, halite, sylvite, rutile, potassium feldspar, Fe-Mn-chloride and other minerals, and ore-forming fluid belong to a complex hydrothermal system containing H2O-NaCl-KClFeCl2CaCl2. H and O isotopic analysis of quartz phenocryst, vein quartz, magnetite, chlorite and gypsum from all alteration zones show that the ore-forming fluid of Duobuza gold-rich porphyry copper deposit consisted mainly of magmatic water, without addition of meteric water. Duobuza gold-rich porphyry copper deposit formed by the primary magmatic fluid (600-950C), which has high oxidation, ultra-high salinity and metallogenic element-rich, exsolution direct from the magma, and it is representative of the typical orthomagmatic end member of the porphyry continuum. Moreover, the fluid evolution model of Duobuza gold-rich porphyry copper deposit has been established. Furthermore, two key factors for formation of large Au-rich porphyry copper deposit have been summed up, which are ore-forming fluids earlier separated from magma and high oxidation magma-mineralization fluid system.

泥河湾盆地大长梁剖面岩石磁学和环境磁学研究

The fluvio-lacustrine sequence in the Nihewan Basin is an important archive of late Pliocene-Pleistocene climate and environment changes in temperate northern China, which provides excellent sources of early human settlements in high latitude East Asia. The recent years have witnessed a considerable progress in the paleomagnetic dating of its stratigraphy, which has notably increased our understanding of a series of important issues such as the early human occupation in the Old World, the infilling history of the Nihewan Basin, and the chronological sequence of the Nihewan faunas. Up to now, the long-term paleoenvironmental changes directly retrieved from this basin, which might influence the evolution and expansion of early humans in the Nihewan Basin, are still poorly constrained, although several paleoclimatic records have been retrieved from this area. In this study, a combined mineral-magnetic and geochemical investigation was carried out on the fluvio-lacustrine sequence from the Dachangliang section at the eastern margin of the basin in order to reveal its rock magnetic and environmental magnetic characteristics and its implications for early human evolution in East Asia. The major findings and conclusions are listed as the following: First, there is an increased cooling coupled with an intensified aridification recorded in the fluvio-lacustrine sequence of the Dachangliang section. The cooling is related to an up-section decrease in propensity to chemical weathering as inferred from an increase in low-field susceptibility after cycling to 700 °C. Close to 700 °C, reacting chlorite is providing the iron source for newly formed very fine-grained ferrimagnetic minerals which enhances the susceptibility signal. The reactivity of chlorite after annealing at temperatures above 600 °C is documented with X-ray diffraction. Second, degrees of chemical weathering in the Nihewan Basin are further estimated by clay mineralogy (i.e. chlorite and illite contents and chlorite/illite ratio) and a series of major element proxies (i.e. Na2O/Al2O3 versus K2O/Al2O3 diagram, Al2O3-(CaO + Na2O)-K2O ternary diagram (A-CN-K), chemical index of alteration (CIA), (CaO + Na2O + MgO)/TiO2, (CaO + Na2O + MgO + K2O)/(TiO2 + Al2O3), CaO/Al2O3 and CaO/TiO2). The up-section decrease in propensity to chemical weathering suggested by the aforementioned rock mangetic measurement is further confirmed by these geochemical analyses. Combining the chemical weathering records from the Nihewan Basin, Chinese Loess Plateau, South China Sea and eastern China, we find that the consecutive decreasing trend in chemical weathering intensity during the late Cenozoic is ubiquitous across China. This pattern may result from a long-term decreasing East Asian summer monsoon and increasing East Asian winter monsoon, and thus a consecutive increasing of aridification and cooling in Asia during the Quaternary. Furthermore, the chemical weathering intensity increased from South China to North China during the Quaternary, in line with the decreasing East Asian summer monsoon and increasing East Asian winter monsoon and thus the gradually intensified aridification and cooling from South China to North China. Third, a combined mineral-magnetic and geochemical investigation provides evidences that the large-amplitude alterations of concentration of magnetic minerals mainly result from preservation/dissolution cycles of detrital magnetic minerals in alternately oxic and anoxic depositional environments. The preservation/dissolution model implies that the high-magnetic and low-magnetic cycles of this sedimentary sequence represent glacial and interglacial climate cycles, respectively. This contribute significnatly to our understanding of the link between climate and magnetic properties. Finally, the paleoclimatic implications of these rock magnetic and geochemical characteristics significantly increase our understanding of the general setting of early humans in high northern latitude in East Asia. We propose that the cold and dry climate may have contributed significantly to the expansion and adaptation of early humans, rather than bringing hardship, as is often thought. The relationship between magnetic properties and climate possibly provides valuable information on the climatic context of the Paleolithic sites in the basin, especially whether the occupation occurred during an interglacial or glacial period.

中国东部上第三系硬粘土的工程地质特性及边坡开挖工程环境效应研究

The engineering geological properties of Neogene hard clays and related engineering problems are frontiers in the fields of Engineering Geology, Soil Mechanics and Rock Mechanics. Recently, it has been recognized that Neogene hard clay is the intermediate type of material between the soil and the rock. Many aspects of them, such as sampling, testing, calculating and engineering process, are special, which could not be researched by means of theories and methods of traditional Soil Mechanics of Rock Mechanics. In order to get real knowledge and instruct the engineering practice, intersect studying of multiple disciplines, including Engineering Geology, Soil Mechanics and Rock Mechanics, etc., is necessary. Neogene hard clay is one of the important study objects of regional problem rocks & soils in our country, which extensively distributed in China, especially in Eastern China. Taking the related areas along the middle line of the Project of Transferring Water from the South to the North (e.g. Nanyang basin, Fangcheng-Baofeng area and Handan-Yongnian area), South-west of Shandong, Xu-Huai area and Beijing area, etc. as main study areas, the paper divided Neogene hard clays into reduction environment dominated origin and oxidation environment dominated origin, which distributed on areas western and eastern to Mount Taihangshan respectively. Intermediate types are also existed in some areas, which mainly distribute near the edges of depositional basins; they are usually of transitions between diluvial and lacustrine deposits. As to Neogene hard clays from Eastern China, the clay particle content is high, and montmorillonite or illite/montmorillonite turbostratic mineral is the dominating clay mineral. The content of effective montmorillonite is very high in each area, which is the basis for the undesirable engineering properties of Neogene hard clays. For hard clays from the same area, the content of effective montmorillonite in gray-greenish hard clay is much higher than that in purple-brownish or brown-yellowish hard clay, which is the reason why the gray-greenish hard clay usually has outstanding expansive property. On the other hand, purple-brownish or brown-yellowish hard clay has relatively less montmorillonite, so its property is better. All of these prove that the composition (clay mineral) of Neogene hard clay is the control factor for the engineering properties. Neogene hard clays have obvious properties such as fissured, overconsolidated and expansive, which are the main reasons that many engineering problems and geological harzards usually occur in Neogene hard clays. The paper systematically elaborates the engineering properties of Neogene hard clays from Eastern China, analyses the relationships between engineering properties and basic indexes. The author introduces the ANN method into the prediction of engineering property indexes of hard clays, which provides a new way for quantitatively assessment and prediction of engineering property indexes. During investigation in the field, the author found that there exists obvious seam-sheared zone between different hard clays in Miocene Xiacaowan formation in Xu-Huai area. Similar phenomenon also exists near the borderline between Neogene hard clays and underlying coal measures in the Southwest of Shandong province, which could be observed in the cores. The discovery of seam-sheard zone has important theoretical and practical significance for engineering stability analysis and revealing the origin of fissures in Neogene hard clays. The macrostructure, medium structure and microstructure together control the engineering properties of hard clays. The author analyses and summarizes the structural effects on hard clays in detail. The complex of the strength property of hard clays is mostly related to the characteristics of fissures, which is one of the main factors that affect the choice of shear strength parameters. So structure-control theory must be inseparably combined with composition-control theory during the engineering geological and rock/soil mechanics research of hard clays. The engineering properties, such as fissured, overconsolidated and expansive, control the instability of engineering behaviors of Neogene hard clays under the condition of excavation, i.e. very sensitive to the change of existence environment. Based on test data analysis, the author elaborates the effects of engineering environment change on the engineering properties. Taking Nanyang basin as example, the author utilizes FEM to study the effects of various factors on stability of cutting canal slopes, than sets forth the characteristics, development laws and formation mechanism of the deformation and failure of hard clay canal slopes, summarizes the protection and reinforcement principles, as well as the protection and remedy steps. On the basis of comparison of engineering properties of domestic and foreign Neogene muddy deposits, in the view of whole globe and associated with the geological characteristics of China, the paper demonstrates that the intermediate type of the material between the soil and the rock, named "hard clay/soft rock", which can not be separated abruptly, really exists in China. The author has given a preliminary classification based on its geological origin and distribution law, which is very significant for promoting the mixture of Engineering Geology, Soil Mechanics and Rock Mechanics. In the course of large scales engineering construction in China, many engineering experiences and testing data are gained, summarizing these testing results and automatically managing them with computer technology are very necessary. The author develops a software named "Hard Clay-Soft Rock Engineering Geological Information Management and Analysis System (HRGIMS)", realizes the automatic and visual management of geo-engineering information, on the basis of information management, the functions of test data analysis and engineering property prediction are strengthened. This system has well merits for practice and popularization.

生物－热催化过渡带沉积成岩演化及其成烃作用研究

The biothermocatalytic transitional zone gas is a new type of natural gas genetic theory, and also an clean, effective and high quality energy with shallow burial depth, wide distribution and few investment. Meanwhile, this puts biothermocatalytic transitional zone gas in important position to the energy resource and it is a challenging front study project. This paper introduces the concept, the present situation of study and developmental trend about biothermocatalytic transitional zone gas in detail. Then by using heat simulating of source rocks and catalysis mechanism analysis in the laboratory and studying structural evolution, sedimentation, diagenesis and the conditions of accumulation formation and so on, this paper also discusses catalytic mechanism and evolutionary model of the biothermocatalytic transitional zone gas formation, and establishes the methods of appraisal parameter and resources prediction about the biothermocatalytic transitional zone gas. At last, it shows that geochemical characteristics and differentiated mark of the biothermocatalytic transitional zone gas, and perfect natural gas genetic theory, and points out the conditions of accumulation formation, distribution characteristics and potential distribution region on the biothermocatalytic transitional zone gas m China. The paper mainly focuses on the formation mechanism and the resources potential about the biothermocatalytic transitional zone gas. Based on filed work, it is attached importance to a combination of macroscopic and microcosmic analysis, and the firsthand data are obtained to build up framework and model of the study by applying geologic theory. Based on sedimentary structure, it is expounded that structural actions have an effect on filling space and developmental cource of sediments and evolution of source rocks. Carried out sedimentary environment, sequence stratigraphy, sedimentary system and diagenesis and so on, it is concluded that diagenesis influences developmental evolution of source rocks, and basic geologic conditions of the biothermocatalytic transitional zone gas. Applying experiment simulating and catalytic simulating as well as chemical analysis, catalytic mechanism of clay minerals is discussed. Combined diagenecic dynamics with isotope fractionation dynamics, it is established that basis and method of resource appraisal about the biothermocatalytic transitional zone gas. All these results effectively assess and predict oil&gas resources about the biothermocatalytic transitional zone gas-bearing typical basin in China. I read more than 170 volumes on the biothermocatalytic transitional zone gas and complete the dissertation' summary with some 2.4 ten thousand words, draw up study contents in some detail and set up feasible experimental method and technologic course. 160 pieces of samples are obtained in oilfield such as Liaohe, Shengli, Dagang and Subei and so on, some 86 natural gas samples and more than 30 crude oil samples. Core profiles about 12 wells were observed and some 300 geologic photos were taken. Six papers were published in the center academic journal at home and abroad. Collected samples were analysised more than 1000 times, at last I complete this dissertation with more than 8 ten thousand words, and with 40 figures and 4 plates. According to these studies, it is concluded the following results and understandings. 1. The study indicates structural evolution and action of sedimentary basin influence and control the formation and accumulation the biothermocatalytic transitional zone gas. Then, the structural action can not only control accommodation space of sediments and the origin, migration and accumulation of hydrocarbon matters, but also can supply the origin of energy for hygrocarbon matters foramtion. 2. Sedimentary environments of the biothermocatalytic transitional zone gas are lake, river and swamp delta- alluvial fan sedimentary systems, having a warm, hot and humid climate. Fluctuation of lake level is from low to high., frequency, and piling rate of sedimentary center is high, which reflect a stable depression and rapidly filling sedimentary course, then resulting in source rocks with organic matter. 3. The paper perfects the natural gas genetic theory which is compound and continuous. It expounds the biothermocatalytic transitional zone gas is a special gas formation stage in continuous evolutionary sequence of organic matter, whose exogenic force is temperture and catalysis of clay minerals, at the same time, having decarbxylation, deamination and so on. 4. The methodology is established which is a combination of SEM, TEM and Engery spectrum analysis to identify microstructure of crystal morphology about clay minerals. Using differential thermal-chromatographic analysis, it can understand that hydrocarbon formation potential of different typies kerogens and catalytic method of all kinds of mineral matrix, and improve the surface acidity technology of clay minerals measured by the pyridine analytic method. 5. The experiments confirm catalysis of clay minerals to organic matter hygrocarbon formation. At low temperature (<300 ℃), there is mainly catalysis of montmorillonite, which can improve 2-3 times about produced gas of organic matters and the pyrolyzed temperature decreased 50 ℃; while at the high temperature, there is mainly catalysis of illite which can improve more than 2 times about produced gas of organic matters. 6. It is established the function relationship between organic matter (reactant) concentration and temperature, pressure, time, water and so on, that is C=f (D, t). Using Rali isotope fractionation effect to get methane isotope fractionation formula. According to the relationship between isotope fractionation of diagenesis and depth, and combined with sedimentary rate of the region, it is estimated that relict gas of the biothermocatalytic transitional zone gas in the representative basin. 7. It is revealed that hydrocarbon formation mechanism of the biothermocatalytic transitional zone gas is mainly from montmorillonite to mixed minerals during diagenesis. In interlayer, a lot of Al~(3+) substitute for Si~(4+), resulting in a imbalance between surface charge and interlayer charge of clay minerals and the occurrence of the Lewis and Bronsted acid sites, which promote to form the carbon cation. The cation can form alkene or small carbon cation. 8. It is addressed the comprehensive identification mark of the biothermo - catalytic transitional zone gas. In the temproal-spatial' distribution, its source rocks is mainly Palaeogene, secondly Cretaceous and Jurassic of Mesozoic, Triassic, having mudy rocks and coal-rich, their organic carbon being 0.2% and 0.4% respectively. The vitrinite reflection factor in source rocks Ro is 0.3-0.65%, a few up to 0.2%. The burial depth is 1000-3000m, being characterized by emerge of itself, reservoir of itself, shallow burial depth. In the transitional zone, from shallow to deep, contents of montmorillonites are progressively reduced while contents of illites increasing. Under SEM, it is observed that montmorillonites change into illite.s, firstly being mixed illite/ montmorillonite with burr-like, then itlite with silk-like. Carbon isotope of methane in the biothermocatatytic transitional zone gas , namely δ~(13)C_1-45‰- -60 ‰. 9. From the evolutionary sequence of time, distribution of the biothermocatalytic transitional zone gas is mainly oil&gas bearing basin in the Mesozoic-Neozoic Era. From the distribution region, it is mainly eastern stuctural active region and three large depressions in Bohaiwang basin. But most of them are located in evolutionary stage of the transitional zone, having the better relationship between produced, reservoir and seal layers, which is favorable about forming the biothermocatalytic transitional zone gas reservoir, and finding large gas (oil) field.

内陆湖沼相和近海沼泽相沉积环境煤中微量元素和矿物的对比研究—以辽宁北票、江西建新和桥头煤研究为例

Using knowledge of geology, geochemistry, coal petrology, mineralogy, by means of a variety of advanced measuring methods such as inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled atomic emission spectrometry (ICP-AES), X-ray powder diffraction (XRD), scanning electron microscopy with energy-dispersive spectrometer(SEM-EDS), sequential chemical extract and density fractions, the characteristics of trace elements and minerals in Jurassic Beipiao coal mine under inland limnetic sedimentary environment and in late Permian Jianxin and Qiaotou coal mines under paralic swamp sedimentary environment were studied. Compared with the average concentration in the world bituminous coals, the Beipiao coal was characterized by relatively high contents of Sc, Ti, Cr, Co, Ni, Zn, Se, Sr, Zr, Y, Ba, REE and Th, and lower contents of V, Rb, Cd, Sn, Pb, Bi and U; while the Jianxin coal was relatively enriched in Li, Sc, Ga, Sr, Y, Nb, Sb, Th and U, with low concentration of Be, Co, Ni, Cu, Ge, Zr, Mo, Cd, Cs, Ba, Pb and Bi; and the Qiaotou coal was enriched in Li, Sc, Sr, Nb, Ta, Zr, REE, Hf, Th and U, with low concentration of Be, V, Co, Ni, Cu, Ge, Mo, Cd, Cs, Ba, Tl, Pb and Bi. The concentrations of Ca, Mg and K in Beipiao coal are higher than those in Jianxin coal and Qiaotou coal, while Fe, S and Ti in Beipiao coal are lower than those in Jianxin coal and Qiaotou coal. The proximate analysis of coal samples was carried out, which indicated that Beipiao coal was medium- to high- ash (5.92-60.68%) with low sulphur coal, and Jianxin coal and Qiaotou coal was medium to high ash (8.85-46.33%) with high sulphur. The reflectivity was measured, which explained that Beipiao coal belonged to high volatile bituminous coal, Jianxin coal was low volatile bituminous coal and Qiaotou coal was low volatile anthracite. Quantitative maceral analyses were studied. The characteristics of rare earth elements (REE) were investigated, which showed that the total contents of REE were higher than that of the world's average content. With the increase of coal's metamorphic grade, the total contents of REE decreased from 98.5 X 10"6 of Beipiao coal to 94.2 X 10"6 of Jianxin coal, and to 75.9 X 10"6 of Qiaotou coal, and 5Eu reduced which indicated that the element Eu depleted. The characteristics of REE was controlled by the metamorphic grade of coal. And REE were mainly absorbed in clay minerals in Beipiao coal samples, while in Jianxin and Qiaotou coal mines, REE were primarily related to clay mineral and pyrite. The variation of trace elements in vertical direction of coal seams was studied, and the results showed that different trace elements differed greatly. The correlation between trace elements and ash were determined. Four major trace elements (aluminium-silicates, sulphide, carbonate and phosphate) accounted for the occurrence and distribution of most elements studied were determined. Coal samples were separated by density fraction, which showed that Cr, Cu, Mo and Pb were closely related to inorganic matters mainly distributed in P >2.6 and dropped remarkably in the density fractions P <2.3 . The occurrences of Co, Cr, Ni, As, Se, Mo, U were studied directly and quantitatively using sequential chemical extract with six steps, which showed that Co. Ni, Mo and U were mainly in the form of mineral, and As, Se chiefly in the form of organic state, while Cr mostly in the form of organic state and mineral. Major mineral phases presented in the Beipiao coal were Kaolinite, illite, quartz, calcite, and small amount of siderite, barite. While major mineral phases in Jianxin and Qiaotou coal were pyrite, kaolinite, and small amount of marcasite, rutile, sphalerite. This is the first time that the chromite in the coal was discovered in China, which indicates that Cr occurrence appeared in the form of chromite. The ratio of Sr/Ba, Sr/Ca and V/Ni in Beipiao coal mine under inland limnetic is smaller than that of in Jianxin and Qiaotou coal mines under paralic swamp. The ratio of K/Na and Th/U of Beipiao coal mine is higher than that of Jianxin and Qiaotou coal mine, which proved that Beipiao coal was not affected by sea water and Jianxin and Qiaotou coal were affected by sea water. Trace elements such as Cr, Ni, Mo in minerals were analyzed by SEM-EDS. The factors controlling the enrichment of trace elements can be divided into syngenetic stage factors and epigenetic stage factors.

东南极格罗夫山地区的土壤特征及其环境研究

The Grove Mountains, including 64 nunataks, is situated on an area about 3200km2 in the inland ice cap of east Antarctica in Princess Elizabeth land (72o20'-73°101S, 73°50'-75o40'E), between Zhongshan station and Dome A, about 450km away from Zhongshan station (69°22'S, 76°22'E). Many workers thought there was no pedogenesis in the areas because of the less precipitation and extreme lower temperature. However, during the austral summer in 1999-2000, the Chinaer 16 Antarctic expedition teams entered the inland East Antarctica and found three soil spots in the Southern Mount Harding, Grove Mountains, East Antarctica. It is the first case that soils are discovered in the inland in East Antarctica. Interestingly, the soils in this area show clay fraction migration, which is different from other cold desert soils. In addition, several moraine banks are discovered around the Mount Harding. The soil properties are discussed as below. Desert pavement commonly occurs on the three soil site surfaces, which is composed of pebbles and fragments formed slowly in typical desert zone. Many pebbles are subround and variegated. These pebbles are formed by abrasion caused by not only wind and wind selective transportation, but also salt weathering and thaw-freezing action on rocks. The wind blows the boulders and bedrocks with snow grains and small sands. This results in rock disintegration, paved on the soil surface, forming desert pavement, which protects the underground soil from wind-blow. The desert pavement is the typical feature in ice free zone in Antarctica. There developed desert varnish and ventifacts in this area. Rubification is a dominant process in cold desert Antarctic soils. In cold desert soils, rubification results in relatively high concentrations of Fed in soil profile. Stained depth increases progressively with time. The content of Fed is increasing up to surface in each profile. The reddish thin film is observed around the margin of mafic minerals such as biotite, hornblende, and magnetite in parent materials with the microscope analyzing on some soil profiles. So the Fed originates from the weathering of mafic minerals in soils. Accumulations of water-soluble salts, either as discrete horizons or dispersed within the soil, occur in the soil profiles, and the salt encrustations accumulate just beneath surface stones in this area. The results of X-ray diffraction analyses show that the crystalline salts consist of pentahydrite (MgSO4-5H2O), hexahydrite (MgSO4-6H2O), hurlbutite (CaBe2(PO4)2), bloedite (Na2Mg(S04)2-4H2O), et al., being mainly sulfate. The dominant cations in 1:5 soil-water extracts are Mg2+ and Na+, as well as Ca2+ and K+, while the dominant anion is SO42-, then NO3-, Cl- and HCO3-. There are white and yellowish sponge materials covered the stone underside surface, of which the main compounds are quartz (SiO2, 40.75%), rozenite (FeSOKkO, 37.39%), guyanaite (Cr2O3-1.5H2O, 9.30%), and starkeyite (MgSO4-4H2O, 12.56%). 4) The distribution of the clay fraction is related to the maximum content of moisture and salts. Clay fraction migration occurs in the soils, which is different from that of other cold desert soils. X-ray diffraction analyses show that the main clay minerals are illite, smectite, then illite-smectite, little kaolinite and veirniculite. Mica was changed to illite, even to vermiculite by hydration. Illite formed in the initial stage of weathering. The appearance of smectite suggests that it enriched in magnesium, but no strong eluviation, which belongs to cold and arid acid environment. 5) Three soil sites have different moisture. The effect moisture is in the form of little ice in site 1. There is no ice in site 2, and ice-cement horizon is 12 cm below the soil surface in site 3. Salt horizon is 5-10 cm up to the surface in Site 1 and Site 2, while about 26cm in site 3. The differentiation of the active layer and the permafrost are not distinct because of arid climate. The depth of active layer is about 10 cm in this area. Soils and Environment: On the basis of the characteristics of surface rocks, soil colors, horizon differentiation, salt in soils and soil depth, the soils age of the Grove Mountains is 0.5-3.5Ma. No remnants of glaciations are found on the soil sites of Mount Harding, which suggests that the Antarctic glaciations have not reached the soil sites since at least 0.5Ma, and the ice cap was not much higher than present, even during the Last Glacial Maximum. The average altitude of the contact line of level of blue ice and outcrop is 2050m, and the altitude of soil area is 2160m. The relative height deviation is about 110m, so the soils have developed and preserved until today. The parental material of the soils originated from alluvial sedimentary of baserocks nearby. Sporepollen were extracted from the soils, arbor pollen grains are dominant by Pinus and Betula, as well as a small amount Quercus, Juglans, Tilia and Artemisia etc. Judging from the shape and colour, the sporepollen group is likely attributed to Neogene or Pliocene in age. This indicates that there had been a warm period during the Neogene in the Grove Mountains, East Antarctica.

中新世以来中国北方风尘堆积的粘土矿物组成及其古环境意义

In northern China, the loess-soil sequence of the last 2.6 Ma, the Hipparion Red-Earth of eolian origin and recently reported Pliocene-Miocene loess-soil sequence provide a near continuous continental eolian record of climatic history for the past 22.0 Ma. This work aims to investigate the composition and structure of clay minerals contained in deposits, and to explore their implications for environmental evolutions over the last 22.0 Ma. Clay minerals, which were extracted from eolian samples collected at Xifeng (0-6.2 MaBP) and Qinan (6.2-22.0 MaBP) sections, were analyzed qualitatively and semi-quantitatively by using X-ray diffraction (XRD), differential thermal analysis (DTA), thermogravimetric analysis (TG) and chemical analysis. The main conclusions are as follows: Over the last 22.0 Ma, the clay mineral assemblage among Quaternary loess-soils, Hipparion Red-Earth, and Miocene loess-soils shows similar components, mainly consisting of illite (55-80%), kaolinite (7-20%), chlorite (4-13%), smectite (2-23%) as results calculated by comparing major peak areas. There are no obvious differences in both types and amounts of clay minerals between loess and interbedded soils, suggesting that overwhelming part of the clay minerals is derived from the source. According to the components of clay minerals, the whole sequence of eolian deposits in the Loess Plateau can be divided into ten clay mineral assemblage zones over the last 22.0 Ma, whose corresponding ages are: 22.0-21.0 MaBP, 21.0-18.0 MaBP, 18-16.2 MaBP, 16.2-13.0 MaBP, 13.0-10.0 MaBP, 10.0-5.5 MaBP, 5.5-4.4 MaBP, 4.4-2.8 MaBP, 2.8-1.0 MaBP, 1.0-0 MaBP, respectively. This may imply that dust supply changed at least nine times over the past 22.0 Ma. The loess illite has a better crystaliinity, higher value of the FWHM and IC, than the interbedd soils. Previous studies indicated that irregular mixed layer minerals could form under relatively warm and humid conditions (Han, 1982). According to the general distribution of clay minerals of zonal soil (Chamley, 1989), the clay mineral assemblage of eolian deposits in Xifeng and Qinan sections is typical of temperature-humid and warm-subarid environment. Therefore, our results indicate climatic environment in Loess Plateau did not change remarkably since 22.0 Ma, and fluctuated between temperature-humid and warm-subarid climate. 4. The illite generally presents poorer crystaliinity during the period of 22.0 to 2.8 MaBP than in the last 2.8 Ma BP, especially at the intervals of 3.5-4.5 Ma BP, 14.0-17.0 MaBP and 20.0-22.0 Ma BP, which indicates that the weathering intensity was stronger in Neogene than in Quaternary. 5. The relatively low ice volume and high global temperature may be responsible for the strange weathering intensity during the interval of the 3.5-4.5 Ma BP, 14.0-17.0 Ma BP and 20.0-22.0 Ma BP.

大方不规则I/S间层的铝层柱化研究

层柱粘土是一类新型的矿物功能材料,具有大孔径、大比表面积、孔径可调、热稳定性好、表面酸性强及含有金属活性组分等特点.它是当前国际粘土矿物学、化学及材料科学界研究的一个热点.该文以贵州大方猫场不规则伊/蒙（简称I/S）间层为研究对象,利用聚合羟基铝作为柱化剂对其进行了层柱化研究,系统地介绍了大方不规则I/S间层的矿物学特征、柱化剂Al<,13>的形态特征、铝层柱I/S间层的制备及表征等.

伊/蒙不规则间层粘土的矿物学特征及其层柱化研究

该文首先详细而系统地介绍了一类新型纳米矿物材料——层柱粘土.论文以贵州大方I/S不规则有序间层粘土为例,在采用多种测试手段了解该矿物的组成、结构及性能的基础上,首次对I/S不规则间层粘土进行了较系统的铝、锆、钛的层柱化研究.XRD、HRTEM、FTIR及DTA-TG共同揭示了大方I/S间层粘土是以Rl型为主的I/S不规则有序间层粘土,化学分析数据计算表明结构中的八面体为二八面体,蒙皂石为钠型蒙脱石.通过对大方I/S不规则间层粘土的铝层柱研究发现,较低的初始铝浓度有利于形成较多的Keggin离子,产物层间距可达3.2～3.5nm,N<,2-BET比表面积达110m<'2>/g.首次对I/S不规则间层粘土进行了钻、钛层柱化研究,所获产物层间距都大于铝层柱者,分别为3.3～4.0nm和3.5~4.7nm.文章首次对层柱I/S不规则间层粘土进行了除层间距以外的孔结构、表面酸性、(水)热稳定性和显微形貌的表征.探讨了层与柱之间、颗粒与颗粒之间的排列和连接对层柱产物性能的影响,比较成功地用IR证据解释了层在机理中四面体的反转问题.最后初步试验了层柱I/S不规则间层粘土对水中重金属pb<'2+>和垃圾淋滤液中COD的去除效果,结果表明卫Ti-I/S对Pb<'2+>的吸附容量可达8.39mg/g,对COD的去除率可高达76.71%.