Northern Minerals eyes globally significant role for Browns Range project amid heightened interest in rare earth elements

Dysprosium is an essential ingredient in the production of NdDyFeB(dysprosium-neodymium-iron-boron)magnets which are used in clean energy and high-tech solutions.Northern Minerals Ltd(ASX:NTU)is progressing the staged development of its Browns Range heavy rare earths project as global events create a unique moment in the rare earth metals industry.

Clay minerals and elemental composition of sediments on different sedimentary units in the northern East China Sea shelf:provenance tracing and genetic mechanism analysis

The composition,provenance,and genetic mechanism of sediment on different sedimentary units of the East China Sea(ECS)shelf are essential for understanding the depositional dynamics environment in the ECS.The sediments in the northern ECS shelf are distributed in a ring-shaped distribution centered on the southwestern Cheju Island Mud.From the inside to the outside,the grain size goes from fine to coarse.Aside from the“grain size effect”,hydrodynamic sorting and mineral composition are important restrictions on the content of rare earth elements(REEs).Based on the grain size,REEs,and clay mineral composition of 300 surface sediments,as well as the sedimentary genesis,the northern ECS shelf is divided into three geochemical zones:southwestern Cheju Island Mud Area(ZoneⅠ),Changjiang Shoal Sand Ridges(ZoneⅡ-1),Sand Ridges of the East China Sea shelf(ZoneⅡ-2).The northern ECS shelf is mostly impacted by Chinese mainland rivers(the Changjiang River and Huanghe River),and the provenance and transport mechanism of sediments of different grain sizes is diverse.The bulk sediments come primarily from the Changjiang River,with some material from the Huanghe River carried by the Yellow Sea Coastal Current and the North Jiangsu Coastal Current,and less from Korean rivers.Among them,surface sediments in the southwestern Cheju Island Mud Area(ZoneⅠ)come mostly from the Changjiang River and partly from the Huanghe River.It was formed by the counterclockwise rotating cold eddies in the northern ECS shelf,which caused the sedimentation and accumulation of the fine-grained sediments of the Changjiang River and the Huanghe River.The Changjiang Shoal Sand Ridges(ZoneⅡ-1)were developed during the early-middle Holocene sea-level highstand.It is the modern tidal sand ridge sediment formed by intense hydrodynamic action under the influence of the Yellow Sea Coastal Current,North Jiangsu Coastal Current,and Changjiang Diluted Water.The surface sediments mainly originate from the Changjiang River and Huanghe River,with the Changjiang River dominating,and the Korean River(Hanjiang River)influencing just a few stations.Sand Ridges of the East China Sea shelf(ZoneⅡ-2)are the relict sediments of the paleo-Changjiang River created by sea invasion at the end of the Last Deglaciation in the Epipleistocene.The clay mineral composition of the surface sediments in the study area is just dominated by the Changjiang River,with the North Jiangsu Coastal Current and the Changjiang Diluted Water as the main transporting currents.

Effects of Enclosure on Grassland Ecological and Economic Benefits in Northern China

Grasslands in northern China serve the country as both an ecological barrier and a livestock production base.There,installing enclosures has been becoming the major grassland restoration measure adopted by many local governments.However,the effects of restoration on both ecological and production benefits of grassland remain unclear for implemented grassland restoration policies.Therefore,a representative rangeland in northern China,the Maodeng pasture in Inner Mongolia Autonomous Region was selected as the study area,and remote sensing monitoring analyses were carried out to quantify the ecological benefits and economic benefits from 2015 to 2021.The results showed that:1) in terms of ecological benefits,the grassland area with a grassland coverage rate of more than 60% accounts for 32.3% of the regional area,and 86.4% of its grassland grew significantly better than the same period in2015,showing a significant improvement in grassland growth.Using the average amount of carbon per unit area as the ecological benefit evaluation index,it increased by 27.1% to 32.48Tg C/yr from 2015 to 2021.2) In terms of economic benefits,both theoretical grass production and livestock carrying capacity increased from 2015 to 2021.Compared to 2015,the theoretical grass production in 2021 increased by 24.8% to 71 900 t.The livestock carrying capacity reached 52 100 sheep units in 2021,nearly 11 000 sheep units more than that in 2015.During the study period,multiple economic indicators(on a per capita basis of permanent residents) for the pastoral area of Xilinhot City to which the Maodeng pasture belongs,have grown steadily.Per capita total income rose from 29 630 yuan(RMB) in2015 to 62 859 yuan(RMB) in 2021.Relying on grassland resources to develop the pastoral ecology also broadens the potential economic development space.Overall,the establishment of the reserve and the experiment of implanting an enclosure policy have had a significant and positive impact on Maodeng pasture’s development from both an ecological and economic perspective.With the support of scientific evidence,enclosure policy can be extended to more than 110 000 km~2 of grasslands in northern China with similar precipitation and temperature conditions,enhancing the productive and ecological potential of grasslands.The above research results will contribute to the scientific formulation of grassland pasture quality improvement plans in northern China.

Satellite observations of coastal upwelling in the northern Arafura Sea

Coastal upwelling is significant for marine ecosystems by lifting nutrient-rich deep waters into the euphotic zone,thereby increasing primary and secondary productivity.The satellite observations show that the northern Arafura Sea(NAS),especially in the coastal region,features high chlorophyll-a(chl-a)concentrations,implying a strong coastal upwelling.However,coastal upwelling in the NAS has not received much attention.Based on a semi-automatic image processing technology,the seasonal and interannual variability of coastal upwelling in the NAS are investigated in this study using satellite-observed sea surface temperature(SST)and wind data.The results suggest that there are seasonal coastal upwelling events in the NAS modulated by upwelling-favorable southeast monsoon(SEM).The annual mean days,mean area,and annual mean intensity of coastal upwelling events during the SEM season are 92 days,6514 km^(2),and-5.31×10^(5),respectively,while the corresponding values during the northwest monsoon(NWM)season are 32 days,5569 km^(2),and-1.41×10^(5).It is also found that the SEM coastal upwelling in the NAS displays prominent interannual variability.The strong upwelling events are found in 2010,2013,2016,and 2017 when the southeast monsoon winds were weaker.Further analysis suggests that at the interannual scale,the upwelling index(UI)averaged in the SEM season is negatively correlated with that of three upwelling indicators.This can be attributed to the limitation of onshore geostrophic flow which is evidenced by the negative correlation between the UI and the alongshore difference in sea surface height.This study highlights the important role of the southeast monsoon in the temporal variability of coastal upwelling in the NAS.

Coral records of Mid-Holocene sea-level highstands and climate responses in the northern South China Sea

High-resolution sea-level data and high-precision dating of corals in the northern South China Sea(SCS)during the Holocene provide a reference and historical background for current and future sea-level changes and a basis for scientific assessment of the evolutionary trend of coral reefs in the SCS.Although sporadic studies have been performed around Hainan Island in the northern SCS,the reconstructed sea level presents different values or is controversial because the indicative meaning of the sea-level indicators were neither quantified nor uniform criteria.Here,we determined the quantitative relationship between modern living coral and sea level by measuring the top surfaces of 27 live Porites corals from the inner reef flat along the east coast of Hainan Island and assessed the accuracy of results obtained using coral as sea-level indicators.Additionally,three in situ fossil Porites corals were analyzed based on elevation measurements,digital X-ray radiography,and U-Th dating.The survey results showed that the indicative meanings for the modern live Porites corals is(146.09±8.35)cm below the mean tide level(MTL).It suggested that their upward growth limit is constrained by the sea level,and the lowest low water is the highest level of survival for the modern live Porites corals.Based on the newly defined indicative meanings,6 new sea-level index points(SLIPs)were obtained and 19 published SLIPs were recalculated.Those SLIPs indicated a relative sea level fluctuation between(227.7±9.8)cm to(154.88±9.8)cm MTL between(5393±25)cal a BP and(3390±12)cal a BP,providing evidences of the Mid-Holocene sea-level highstand in the northern SCS.Besides that,our analysis demonstrated that different sea-level histories may be produced based on different indicative meanings or criteria.The dataset of 276 coral U-Th ages indicates that coral reef development in the northern SCS comprised the initial development,boom growth,decline,and flourishing development again.A comparison with regional records indicated that synergistic effects of climatic and environmental factors were involved in the development of coral reefs in the northern SCS.Thus,the cessation of coral reef development during the Holocene in the northern SCS was probably associated with the dry and cold climate in South China,as reflected in the synchronous weakening of the ENSO and East Asian summer monsoon induced by the reduction of the 65°N summer insolation,which forced the migration of the Intertropical Convergence Zone.

Enrichment model and major controlling factors of below-source tight oil in Lower Cretaceous Fuyu reservoirs in northern Songliao Basin,NE China

Based on the geochemical,seismic,logging and drilling data,the Fuyu reservoirs of the Lower Cretaceous Quantou Formation in northern Songliao Basin are systematically studied in terms of the geological characteristics,the tight oil enrichment model and its major controlling factors.First,the Quantou Formation is overlaid by high-quality source rocks of the Upper Cretaceous Qingshankou Formation,with the development of nose structure around sag and the broad and continuous distribution of sand bodies.The reservoirs are tight on the whole.Second,the configuration of multiple elements,such as high-quality source rocks,reservoir rocks,fault,overpressure and structure,controls the tight oil enrichment in the Fuyu reservoirs.The source-reservoir combination controls the tight oil distribution pattern.The pressure difference between source and reservoir drives the charging of tight oil.The fault-sandbody transport system determines the migration and accumulation of oil and gas.The positive structure is the favorable place for tight oil enrichment,and the fault-horst zone is the key part of syncline area for tight oil exploration.Third,based on the source-reservoir relationship,transport mode,accumulation dynamics and other elements,three tight oil enrichment models are recognized in the Fuyu reservoirs:(1)vertical or lateral migration of hydrocarbon from source rocks to adjacent reservoir rocks,that is,driven by overpressure,hydrocarbon generated is migrated vertically or laterally to and accumulates in the adjacent reservoir rocks;(2)transport of hydrocarbon through faults between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downward through faults to the sandbodies that are separated from the source rocks;and(3)migration of hydrocarbon through faults and sandbodies between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downwards through faults to the reservoir rocks that are separated from the source rocks,and then migrates laterally through sandbodies.Fourth,the differences in oil source conditions,charging drive,fault distribution,sandbody and reservoir physical properties cause the differential enrichment of tight oil in the Fuyu reservoirs.Comprehensive analysis suggests that the Fuyu reservoir in the Qijia-Gulong Sag has good conditions for tight oil enrichment and has been less explored,and it is an important new zone for tight oil exploration in the future.

Spatial differences of Sustainable Development Goals(SDGs)among counties(cities)on the northern slope of the Kunlun Mountains

The county(city)located on the northern slope of the Kunlun Mountains is the primary area to solidify and extend the success of Xinjiang Uygur Autonomous Region,China in poverty alleviation.Its Sustainable Development Goals(SDGs)are intertwined with the concerted economic and social development of Xinjiang and the objective of achieving shared prosperity within the region.This study established a sustainable development evaluation framework by selecting 15 SDGs and 20 secondary indicators from the United Nations’SDGs.The aim of this study is to quantitatively assess the progress of SDGs at the county(city)level on the northern slope of the Kunlun Mountains.The results indicate that there are substantial variations in the scores of SDGs among the nine counties and one city located on the northern slope of the Kunlun Mountains.Notable high scores of SDGs are observed in the central and eastern regions,whereas lower scores are prevalent in the western areas.The scores of SDGs,in descending order,are as follows:62.22 for Minfeng County,54.22 for Hotan City,50.21 for Qiemo County,42.54 for Moyu County,41.56 for Ruoqiang County,41.39 for Qira County,39.86 for Lop County,38.25 for Yutian County,38.10 for Pishan County,and 36.87 for Hotan County.The performances of SDGs reveal that Hotan City,Lop County,Minfeng County,and Ruoqiang County have significant sustainable development capacity because they have three or more SDGs ranked as green color.However,Hotan County,Moyu County,Qira County,and Yutian County show the poorest performance,as they lack SDGs with green color.It is important to establish and enhance mechanisms that can ensure sustained income growth among poverty alleviation beneficiaries,sustained improvement in the capacity of rural governance,and the gradual improvement of social security system.These measures will facilitate the effective implementation of SDGs.Finally,this study offers a valuable support for governmental authorities and relevant departments in their decision-making processes.In addition,these results hold significant reference value for assessing SDGs at the county(city)level,particularly in areas characterized by low levels of economic development.

Depression&Anxiety Among Women in Northern Kenya:Sociodemographic Predictors

This article documents socio-demographic predictors of anxiety and depression among Maasai women in resource poor settings in Northern Kenya.These findings emerged from the findings of a dissertation research that aimed to establish the treatment effectiveness of an eclectic model of psychoeducation(PE)in treating depressive and anxiety symptoms among the women.The study adopted a quasi-experimental research design which had an experimental group(EG)and control group(CG).The population for the study was 686 female members of Conservation Enterprise Groups(CEG)in Laikipia County,from which a sample of 200 were recruited for the study(EG,n=100 and CG,n=100),at 80%power and 30%effective size.The Beck’s Depression Inventory(BDI)and Beck’s Anxiety Inventory(BAI)tools were used to assess the symptoms of depression and anxiety,respectively.The PE was provided as an intervention treatment to the EG at the middle and end of the study,after which the respondents were tested for symptoms of depression.The study established the prevalence of depression as 26.7%and 31.3%for anxiety and disorders,among women in the region.Data was analyzed using SPSS Version 21.0.

Spatial and Temporal Analysis of Maximum and Minimum Temperature Trends in Northern Sudan during (1990-2019)

The study addresses an urgent and globally significant issue of climate change by focusing on the detailed spatial and temporal analysis of temperature trends in Northern Sudan. It fills a critical research gap by providing localized data over a substantial period (1990-2019), which could help in understanding the nuanced impacts of climate change in Sahel regions like Northern Sudan. In addition, the comprehensive coverage of both spatial and temporal dimensions, supported by a substantial dataset from five meteorological stations, provides a thorough understanding of the subject area. The utilization of robust statistical methods (Mann-Kendall test and Sen’s slope analysis) for analyzing temperature trends adds scientific rigor and credibility to the findings. Our results reveal a consistently increasing trend in maximum temperatures across most stations, particularly during the hot season (AMJ). However, the wet season (JAS) shows high maximum temperatures but no significant trend. Moreover, significant increasing trends in minimum temperatures were observed in all stations except Abu Hamed, where the trend, although increasing, did not reach statistical significance during the hot and cold seasons, and the coldest temperatures were observed during the cold season. These findings underscore the complex temperature dynamics in Northern Sudan and highlight the need for continued monitoring and adaptive measures in response to ongoing climate changes in the region.

A review of mineral systems and associated tectonic settings of northern Xinjiang,NW China

In this paper we present a review of mineral systems in northern Xinjiang, NW China, focussing on the Tianshan, West and East Junggar and Altay orogenic belts, all of which are part of the greater Central Asian Orogenic Belt （CAOB）. The CAOB is a complex collage of ancient microcontinents, island arcs, oceanic plateaux and oceanic plates, which were amalgamated and accreted in Early Palaeozoic to Early Permian times. The establishment of the CAOB collage was followed by strike-slip movements and affected by intraplate magmatism, linked to mantle plume activity, best exemplified by the 250 Ma Siberian Traps and the 280 Ma Tarim event. In northern Xinjiang, there ale numerous and economically important mineral systems. In this contribution we describe a selection of representative mineral deposits, including subduction-related porphyry and epithermal deposits, volcanogenic massive sulphides and skarn systems. Shear zone-hosted Au lodes may have first formed as intrusion-related and subsequently re-worked during strike-slip deformation. Intraplate magmatism led to the emplacement of concentrically zoned （Alaskan-style） mafic-ultramafic intrusions, many of which host orthomagmatic sulphide deposits. A huge belt of pegmatites in the Altay orogen, locally hosts world-class rare metal deposits. Roll-front,

Physicochemistry and Mineralogy of Storm Dust and Dust Sediment in Northern China

Dust sediments collected from 1995 to 1998 in Beijing, Dunhuang, Inner Mongolia, Kashi, the Kunlun Mountains, Lanzhou, Ningxia, the Taklimakan Desert, and Xi’an, China, were characterized in terms of their physical, chemical, and mineralogical properties. Most aerosols and dust analysed ranged in texture from silty clay to clay loam. Their median particle diameters (Mds) generally ranged between 5 to 63 μm, coinciding with those of loess from central China and the ?nest sand from northwestern China. The dust sediments were characterized by a predominance of SiO2 and Al2O3, followed by K2O. Their SiO2/Al2O3 and K2O/SiO2 molar ratios ranged from 5.17 to 8.43 and from 0.009 to 0.0368, respectively. The mass concentration spectrum during a dust storm showed a single peak, rather than the triple peak generally observed under clear sky conditions. The dominant minerals were chlorite, illite, calcite, and dolomite. These physical, chemical, and mineralogical properties were consistent with those of aeolian soils and loess in western and central China. The results suggest that aerosols and ?ne-grained fractions of dust sediments collected in northern China are mainly composed of soil material transported from the arid and semiarid regions of China and Mongolia by prevailing winds. The rate of deposition and properties of dust falling on eastern China were strongly in?uenced by meteorological conditions, season, latitude, longitude, and altitude of the sampling sites.

Characteristics of mineral elements in shoots of three annual halophytes in a saline desert, Northern Xinjiang

Halophytes are valuable salt-, alkali- and drought-resistant germplasm resources. However, the char- acteristics of mineral elements in halophytes have not been investigated as intensively as those in crops. This study attempted to investigate the characteristics of mineral elements for annual halophytes during their growth period to reveal their possible physiological mechanisms of salt resistance. By using three native annual halophytes （Salsola subcrassa, Suaeda acuminate and Petrosimonia sibirica） distributed in the desert in Northern Xinjiang of China, the dynamic changes in the mineral element contents of annual halophytes were analyzed through field sampling and laboratory analyses. The results demonstrated that the annual halophytes were able to absorb water and mineral nutrients selectively. In the interaction between the annual halophytes and saline soil, the adaptability of the annual halophytes was manifested as the accumulation of S, Na and CI during the growth period and maintenance of water and salt balance in the plant, thus ensuring their selective absorption of N, P, K, Ca, Mg and other mineral nutrients according to their growth demand. By utilizing this property, halophyte planting and mowing （before the wilting and death periods） could bioremediate heavy saline-alkali soil.

Early Paleozoic Magmatism and Gold Mineralization in the Northern Altun, NW China

This paper discusses the relationships between granitic magmatism and gold mineralization and the exhumation history of the Dapinggou gold deposit in northern Altun, NW China based on the geochronological data, including zircon U-Pb ages, Rb-Sr isochron age and 40Ar-39Ar dating and MDD modeling data. The main granitic magmatism age in this area is attained from the ID TIMS U-Pb geochronology of zircons from the Kuoshibulak granite, the biggest granite in the northern Altun area, which gives a concordant age of 443±5 Ma in the Late Ordovician. Zircon ID TIMS U-Pb geochronology of the West Dapinggou biotite granite west of the Dapinggou gold deposit gives concordant ages around 485±10 Ma, representing the early stage of Ordovician magmatism. The Rb-Sr isochron age (487±21 Ma) of 6 quartz inclusion samples from quartz veins in this gold deposit is very close to that of the West Dapinggou granite. MDD modeling of step heating 40Ar-39Ar data of K-feldspar from the same West Dapinggou biotite granite gives a rapid cooling history from 300℃ to 150℃ during 200-185 Ma. According to the age data and the geological setting of this area, we conclude that the Dapinggou gold deposit was formed at the early stage of the Early Paleozoic granitic magmatism in northern Altun, and exhumed in the Early Jurassic due to the normal faulting of the Lapeiquan detachment. The Early Paleozoic magmatism may provide heat source and produce geological fluids, which are very important for gold mineralization. Exhumation in the Mesozoic caused the uplift of the deposit towards the ground surface.

Glass and Mineral Chemistry of Northern Central Indian Ridge Basalts:Compositional Diversity and Petrogenetic Significance

The glass and mineral chemistry of basaits examined from the northern central Indian ridge （NCIR） provides an insight into magma genesis around the vicinity of two transform faults： Vityaz （VT） and Vema （VM）. The studied mid-ocean ridge basalts （MORBs） from the outer ridge flank （VT area） and a near-ridge seamount （VM area） reveal that they are moderately phyric plagioclase basalts composed of plagioclase （phenocryst [An60-90] and groundmass [An35-79]）, olivine （Fo81-88）, diopside （Wo45-51, En25-37, Fs14-24）, and titanomagnetite （FeOt -63.75 wt% and TiO2 -22.69 wt%）. The wholerock composition of these basalts has similar Mg# [mole Mg/mole（Mg＋Fe2＋）] （VT basalt： -0.56-0.58; VM basalt： -0.57）, but differ in their total alkali content （VT basalt： -2.65; VM basalt： -3.24）. The bulk composition of the magma was gradually depleted in MgO and enriched in FeOt, TiO2, P2O5, and Na2O with progressive fractionation, the basalts were gradually enriched in Y and Zr and depleted in Ni and Cr. In addition, the ∑REE of magma also increased with fractionation, without any change in the （La/ Yb）N value. Glass from the VM seamount shows more fractionated characters （Mg#： 0.56-0.57） compared to the outer ridge flank lava of the VT area （Mg#： 0.63-0.65）. This study concludes that present basalts experienced low-pressure crystallization at a relatively shallow depth. The geochemical changes in the NCIR magmas resulted from fractional crystallization at a shallow depth. As a consequence, spinel was the first mineral to crystallize at a pressure 〉10 kbar, followed by Fe-rich olivine at 〈10 kbar pressure.

Dual Control of Depositional Facies on Uranium Mineralization in Coal-bearing Series： Examples from the Tuanyushan Area of the Northern Qaidam Basin, NW China

The uranium deposits in the Tuanyushan area of northern Qaidam Basin commonly occur in coal-bearing series. To decipher the U-enrichment mechanism and controlling factors in this area, a database of 72 drill cores, including 56 well-logs and 3 sampling wells, was examined for sedimentology and geochemistry in relation to uranium concentrations. The results show that coal-bearing series can influence uranium mineralization from two aspects, i.e., spatial distribution and dynamic control. Five types of uranium-bearing rocks are recognized, mainly occurring in the braided river and braided delta sedimentary facies, among which sandstones near the coals are the most important. The lithological associations of sandstone-type uranium deposits can be classified into three subtypes, termed as U-coal type, coal-U-coal type, and coal-U type, respectively. The coal and fine siliciclastic rocks in the coal- bearing series confined the U-rich fluid flow and uranium accumulation in the sandstone near them. Thus, the coal-bearing series can provide good accommodations for uranium mineralization. Coals and organic matters in the coal-bearing series may have served as reducing agents and absorbing barriers. Methane is deemed to be the main acidolysis hydrocarbon in the U-bearing beds, which shows a positive correlation with U-content in the sandstones in the coal-bearing series. Additionally, the 613C in the carbonate cements of the U-bearing sandstones indicates that the organic matters, associated with the coal around the sandstones, were involved in the carbonation, one important component of alteration in the Tuanyushan area. Recognition of the dual control of coal-bearing series on the uranium mineralization is significant for the development of coal circular economy, environmental protection during coal utilization and the security of national rare metal resources.

Spatial-temporal Frame,Evolution and Mineralization of the Northern Qilian Metallogenic Province

Four metallogenic epochs occurred in different tectonic environments during theevolution of the Northern Qilian metallogenic province through the geological time. The Mid-dle Proterozoic metallogenic epoch witnessed the tectonic environment of crustal breakupcaused by mantle diapirism, in which ultramafic-mafic rocks were intruded along beep faultbelts and the superlarge Jinchuan magmatic Cu-Ni sulphide deposit was formed. In theMiddle-Late Proterozoic metallogenic epoch the crust was further broken to form anintracontinental rift, in which the Chenjiamiao style massive Cu-Fe sulphide deposits hosted bybasic volcanic tuff were formed in the lower volcano-sedimentary sequence, while the largesedex type Jingtieshan style Fe-Cu deposits were formed within the upper abyssal carbon-richargillaceous sedimentary sequence. The Early Palaeozoic saw the aulacogen environment, with-in which the Baiyinchang style superlarge massive base and precious metal sulphide depositshosted by quartz keratophyric tuff were formed in the Middle-Late Cambrian rifted island arcand the massive Cu-Zn sulphide deposits and magmatic chromite deposits associated with theophiolite suite were formed in the Early-Middle Ordovician, and the Honggou style massiveCu-Fe sulphide deposits hosted by spilite were formed in the Late Ordovician back-arc basinenvironment. In the Late Palaeozoic-Meso-Cenozoic, the metallogenic province went into anintracontinental orogenic stage characterized by compressive tectonic environment, in whichthere occurred carbonate-quartz vein type and tectono-alteration gold deposits associated withductile-shear structures.

New Discovery of Post-Magmatic Pyrite in Natural Coke at Yangliu Coalmine,Northern China

Objective Material exchange between magma and coal has recently received much attention, with published studies dedicated mainly to intrusion-related geochemical anomalies(An et al., 2017). It is found that magmatism not only alters the chemical compositions of coal seams, but also brings new minerals to natural coke. Although some studies have related magmatic water to secondary minerals in the natural coke, the mineral formation

Comparisons on Mineralogy and Lithology between Paleozoic Marine and Lacustrine Dolostones, Northern China

1 Introduction Dolomite[Ca Mg(CO3)2],a common mineral in carbonate rocks,can be found in various geological settings from Precambrian to modern age,and is widely reported in almost all sedimentary and digenetic

Mineralogy, Geochemistry and Palaeomagnetism of Mafic Dykes from Kumaun Lesser Himalaya: Implication on Petrogenesis, Tectonic Setting and Timing of Mafic Magmatism in Northern Part of Indian Lithosphere

Occurrence of mafic dykes in Himalaya has been intriguing and debated since long because of its difficulty to ascent and emplacement through a thickened crust.Mafic dykes in Kumaun Lesser Himalaya(KLH)of central Indian

Genesis of pyroxenite veins in supra-subduction zone peridotites:Evidence from petrography and mineral composition of Egiingol massif(Northern Mongolia)

Swarms of orthopyroxenite and websterite veins are found within Egiingol residual SSZ peridotite massif of Dzhida terrain(Central Asian Orogenic Belt,Northern Mongolia).The process of Egiingol pyroxenite veins formation is investigated using new major and trace element analyses of pyroxenite minerals,calculations of closure temperatures and composition of equilibrium melt.The pyroxenites show abundant petrographic and geochemical evidence for replacement of the residual peridotite minerals by ortho-and clinopyroxene due to melt-rock interaction.Relics of peridotite olivines are found in pyroxenites,Cr#of spinel increases from peridotites to pyroxenites,and compositions of ortho-and clinopyroxene change from peridotite to pyroxenite.The authors show that calculated equilibrium melts for investigated pyroxenites are very similar to compositions of boninite lavas from the Dzhida terrain.Therefore,formation of pyroxenite veins most likely resulted from percolation of boninite melts through the Egiingol peridotites.Orthopyroxenite veins formed at first,followed by websterite veins.Thus,the authors assume that pyroxenite veins represent the channels for boninitic melts migration in supra-subduction environment.