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An investigation on the wind profiles and gravity wave dynamics in MLT region based on the meteor radars from the Meridian Project

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Earth and Planetary Physics 2025年第1期9卷 29-38页

作者： Tai Liu Zhe Wang MengXi Shi Willie Soon ShiCan Qiu department of Geophysics College of the Geology Engineering and GeomaticsChang’an UniversityXi’an 710054China Center for environmental Research and Earth Sciences(CERES) SalemMA 01970USA Institute of Earth Physics and Space Science(ELKH EPSS) 9400SopronHungary

The meteor radar can detect the zenith angle,azimuth,radial velocity,and altitude of meteor trails so that one can invert the wind profiles in the mesosphere and low thermosphere(MLT)region,based on the Interferometric and Doppler *** this paper,the horizontal wind field,gravity wave(GW)disturbance variance,and GW fluxes are analyzed through the meteor radar observation from 2012−2022,at Mohe(53.5°N,122.4°E)and Zuoling(30.5°N,114.6°E)stations of the(Chinese)Meridian *** Lomb−Scargle periodogram method has been utilized to analyze the periodic variations for time series with observational data *** results show that the zonal winds at both stations are eastward dominated,while the meridional winds are southward *** variance of GW disturbances in the zonal and meridional directions increases gradually with height,and there is a strong pattern of annual *** zonal momentum flux of GW changes little with height,showing weak annual *** meridional GW flux varies gradually from northward to southward with height,and the annual periodicity is *** both stations,the maximum values of zonal and meridional wind occur close to the peak heights of GW flux,with opposite *** observational evidence is consistent with the filtering *** horizontal wind velocity,GW flux,and disturbance variance of the GW at Mohe are overall smaller than those at Zuoling,indicating weaker activities in the MLT at *** power spectral density(PSD)calculated by the Lomb−Scargle periodogram shows that there are 12-month period and 6-month period in horizontal wind field,GW disturbance variance and GW flux at both stations,and especially there is also a 4-month cycle in the disturbance *** PSD of the 12-month and 6-month cycles exhibits maximum values below 88 km and above 94 km.

关键词： meteor radar wind field gravity wave Lomb−Scargle method

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Geochemical Study of Rare Earth Elements on Four Attapulgite Clay Deposits in Jiangsu and Anhui Provinces,China

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Journal of Rare Earths 2003年第4期21卷 478-483页

作者：陈天虎徐晓春鲁安怀岳书仓汪家权彭书传 department of Resources and environmental Sciences department of geology

This paper discussed in detail about the REE component and the characteristics of the different kinds of attapulgite clay ores as well as basalts, weathered basalts in four localities of attapulgite clay deposits of Jiangsu and Anhui Provinces of China. It is concluded that the half weathered basalts have not distinct REE fractionation and strong weathered basalts have HREE loss in the process of the basalts weathered to form smectite group minerals. And the lateritic montmorillonite clays that formed from the basalts weathering have a distinct Ce positive anomaly, a little MREE loss and LREE and HREE renew enrichment. That reflects the particular oxidation condition in the Earth's surface and the adsorption of the colloid solution of the lake water in the basin of the continent in the time of the clays formed. The attapulgite clays produced by the reaction between basalts with lake water in the original place of the basin have same REE characteristics as that of the basalts and the weathered basalts. This shows that REE does not transfer heavily in the progressive chemical weathering process. The sedimentary attapulgite clays have also a similar REE component and characteristic parameters to the basalts and the weathered basalts, and have a distinct Eu negative anomaly and a big value of LREE/HREE, which shows that the sedimentary clay came from the weathered basalts, and REE partitioning patterns characters of the clays are controlled by the residual material of the weathered basalts.

关键词： geochemistry attapulgite basalt rare earths

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Authigenic gypsum found in gas hydrate-associated sediments from Hydrate Ridge, the eastern North Pacific

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Science China Earth Sciences 2004年第3期47卷 280-288页

作者： Erwin Suess Dirk Rickert department of Marine environmental geology Research Centre of Marine Geology University of Kiel Kiel D-24148 Germany Department of Marine Environmental Geology Research Centre of Marine Geology University of Kiel Kiel D-24148 Germany

Characteristic gypsum micro-sphere and granular mass were discovered by bin-ocular microscope in the gas hydrate-associated sediments at cores SO143-221 and SO143/TVG40-2A respectively on Hydrate Ridge of Cascadia margin, the eastern North Pacific. XRD patterns and EPA analyses show both micro-sphere and granular mass of the crystals have the typical peaks and the typical main chemical compositions of gypsum, although their weight percents are slightly less than the others in the non-gas hydrate-associated marine regions. SEM pictures show that the gypsum crystals have clear crystal boundaries, planes, edges and cleav-ages of gypsum in form either of single crystal or of twin crystals. In view of the fact that there are meanwhile gas hydrate-associated authigenic carbonates and SO42--rich pore water in the same sediment cores, it could be inferred reasonably that the gypsums formed also authigenically in the gas hydrate-associated environment too, most probably at the interface between the down-ward advecting sulfate-rich seawater and the below gas hydrate, which spilled calcium during its formation on Hydrate Ridge. The two distinct forms of crystal intergrowth, which are the granular mass of series single gypsum crystals at core SO143/TVG40-2A and the microsphere of gypsum crystals accompanied with detrital components at core SO143-221 respectively, indicate that they precipitated most likely in different interstitial water dynamic environments. So, the distinct authigenic gypsums found in gas hydrate-associated sediments on Hydrate Ridge could also be believed as one of the parameters which could be used to indicate the presence of gas hydrate in an unknown marine sediment cores.

关键词： authigenic gypsum, gas hydrate-associated sediment, Hydrate Ridge, eastern North Pacific.

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Magnetic Characterization of Amphibolites from the Fomopéa Pluton(West Cameroon):Their Implication in the Pan-African Deformation of the Central African Fold Belt

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Acta Geologica Sinica(English Edition) 2012年第1期86卷 73-84页

作者： NJANKO Théophile FOZING Eric Martial KWéKAM Maurice YAKEU SANDJO Angéline Flore NJONFANG Emmanuel Laboratory of environmental geology Department of Earth SciencesDschang University Laboratory of geology ENS Yaounde I University

The Fomopea granitic pluton is emplaced in gnessic and amphibolitic basement. These gneissic and amphibolitic basement rocks are represented in the pluton＇s body as sub-rounded, elongated or stretched xenoliths. Amphibolitic xenoliths display testimonies of two main tectonic events namely：（i） El flattening deformation event characterized by a NW-SE to E-W foliation with a best pole at 246/57 and a mineral stretched lineation with a best line at 293/47; and （ii） E2 compressive event typified by （1） N-S to NNE-SSW steeply dipping foliation; （2） S-type flexion-fold indicating a sinistral shear movement. These amphibolite rocks indicate a magnetic susceptibility magnitude （Km） range from 418 ~SI to 90092 IISI for 87% of the stations showing a ferromagnetic behavior. K-T curves reveal the presence of Ti-poor magnetite as susceptibility mineral carrier. Magnetic foliation and lineation suggest that the N-S strike direction observed in the Bamendou amphibolite is, as pointed out elsewhere in the Central African Fold Belt, of paramount importance in the tectonic evaluation of the Fomopea area, since it has most likely acted as major deformation phase in the second tectonic event in the belt.

关键词： amphibolite anisotropy of magnetic susceptibility (AMS) Pan-African fold belt Cameroon

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Mineralogy, Geochemistry and Geotectonic of Plagiogranites from Shahre-Babak Ophiolite, Zagros Zone, Iran

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Journal of Earth Science 2016年第3期27卷 507-518页

作者： Fatemeh Sepidbar Hassan Mirnejad department of geology University of Tehran department of Earth and environmental Earth Sciences Miami University

Shahre-Babak ophiolite is a part of the inner Zagros ophiolite belt in Iran. Major parts of intrusive masses of Share-Babak ophiolite are gabbro and plagiogranite. The SiO2 versus Na2O＋K2O diagram shows that the palgiogranites are related to calk-alkaline series. Rare earth elements exhibit relatively similar pattern that indicates these rocks are syngenetic. Also, REE patterns display an enrichment of LREE compared to HREE, and are characterized by flat to slightly concaveup patterns from Gd to Yb. Such patterns contrast sharply with those of plagiogranites in more complete ophiolite sequences, such as the Semail ophiolite, Oman, or the Troodos ophiolite, Cyprus, and Neyriz, where patterns are much flatter and slightly LREE-depleted. The slightly LREE-enriched patterns of the Shahre-Babak plagiogranites support a partial melting origin for them. The low TiO2, Nb, Ta content and high LREE concentrations of the Shahre-Babak plagiogranites indicate that the rocks were likely derived from the anatexis of amphibolites, which were related to hydrothermal alteration of gabbros in intra-oceanic back-arc basin.

关键词： plagiogranite back-arc basin Share-Babak ophiolite Neo-Tethys Iran

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Interrelationships between Deformation and Metamorphic Events across the Western Hinterland Zone, NW Pakistan

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Journal of Earth Science 2016年第4期27卷 584-598页

作者： Asghar Ali Mustafa Yar Muhammad Asif Khan Shah Faisal department of geology University of Peshawar department of Earth and environmental Sciences Bahria University National Centre of Excellence in geology University of Peshawar Earth and environmental Sciences IKBAS University of British Columbia

Microscopic to mesoscopic structural investigations and foliation intersection axes（FIAs） preserved in porphyroblasts reveal a very complex history of deformation and tectonism within the southwestern part of the western hinterland zone along the northern margin of the Indian plate, NW Pakistan. D_1, D_2, and D_3 related structures in the southwestern part resemble the F_1/F_2, F_3, and F_4 related structures in the northeastern part of the western hinterland zone. These structures developed at the same time through the same changes in the direction of bulk shortening in southwestern and northeastern parts of the western hinterland zone. FIA set 1 indicates NW-SE shortening. The D_2 fabrics, mineral lineations and fold axes indicate E-W shortening. FIA set 2, D_3 fold axes and mineral lineations indicate NNE-SSW shortening. D_3 deformation event is equivalent to the F_4 deformation event in the northeastern part of the western hinterland zone. D_4 fold axes, mineral stretching lineations and axial plane foliation suggest ENE-WSW shortening. The D_4 NNW-SSE fabrics, which formed in the region after the formation of the MMT（main mantle thrust）, Khairabad-Panjal thrust fault, Hissartang thrust fault and MBT（main boundary thrust）, likely resulted from ENE-WSW bulk shortening related to development of the Hazara-Kashmir syntaxis.

关键词： FIA western hinterland zone microstructure mesostructure metamorphism tectonics,NW Pakistan.

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Crystallization Conditions and Mineral Chemistry in the East of Tafresh, Central Iran, with Insights into Magmatic Processes

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Acta Geologica Sinica(English Edition) 2019年第6期93卷 1755-1772页

作者： Davood RAEISI Hassan MRNEJAD department of geology Faculty of ScienceUniversity of TehranTehranIran department of geology and environmental Earth Sciences Miami UniversityOxfordOhioUSA

The Tafresh granitoids are located at the central part of the Urumieh-Dokhtar Magmatic Arc(UDMA)in *** rocks,mainly consisting of diorite and granodiorite,were emplaced during the Early *** are composed of varying proportions of plagioclase+K-feldspar+hornblende±quartz±*** diagrams and chemical indices of amphibole phases reveal a calc-alkaline affinity and fall clearly in the crust-mantle mixed source *** estimated pressure,derived from Al in amphibole barometry,is approximately 3 *** granitoids are I-type,metaluminous and belong to the calc-alkaline *** are all enriched in light rare earth elements and large ion lithophile elements,depleted in high field strength elements and display geochemical features typical of subduction-related calc-alkaline arc *** crystal size distribution(CSD)line patterns from the granitoids show a non-straight trend which points to the effect of physical processes during *** presence of numerous mafic enclaves,sieve texture and oscillatory zoning along with the CSD results show that magma mixing in the magma chamber had an important role in the petrogenesis of Tafresh ***,the CSD analysis suggests that the plagioclase crystals were crystallized in a time span of less than 1000 years,which is indicative of shallow depth magma crystallization.

关键词： crust-mantle mixed source I-type subduction crystal size distribution magma mixing Urumieh-Dokhtar Magmatic Arc

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Responses of Ryegrass(Lolium perenne L.) Grown in Mudflats to Sewage Sludge Amendment

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Journal of Integrative Agriculture 2014年第2期13卷 426-433页

作者： BAI Yan-chao GU Chuan-hui TAO Tian-yun ZHU Xiao-wen XU Yi-ran SHAN Yu-hua FENG Ke College of environmental Science and Engineering Yangzhou University department of geology Appalachian State University

Sewage sludge amendment （SSA） is an alternative waste disposal technique and a potential way to increase fertility of mudflats for crop growth. The present study aimed to assess the suitability of SSA by assessing the nitrogen （N） and phosphorous （P） uptakes, heavy metal accumulation, growth, biomass, and yield response of ryegrass （Lolium perenne L.） at 0, 30, 75, 150, and 300 t ha-1 SSA rates at various growth stages. The results showed that the highest biomass ofryegrass at seedling and vegetative stages were at 300 and 150 t ha-1 SSA rate, respectively. The increments of ryegrass yield at reproductive stage at 30, 75, 150, and 300 t ha1 SSA rates were 98.0, 122.6, 88.1, and 61.2%, compared to unamended soil. N and P concentrations in ryegrass increased with increasing SSA rates at all stages except N and P in roots dropped significantly at 300 t ha-1 rate at vegetative stage. The metal concentration for Mn, Cu, Zn, Ni, Cd, Cr, and Pb in shoot of ryegrass at 300 t ha-1 S SA rate increased by 0.63-, 2.34-, 15.02-, 0.97-, 10.00-, 0.01- and 1.13-fold, respectively, compared to unamended soil. However, heavy metal concentrations in shoot of ryegrass were lower than the standard for forage products in China. The study suggested that sewage sludge amendment in mudflat soils might be feasible. However, the impacts of sludge application on edible crop plants and soil environment need further investigations.

关键词： sewage sludge mudflat soil ryegrass growth metals

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Facies Analysis and Sequence Stratigraphy of the Qal'eh Dokhtar Formation(Middle-Upper Jurassic) in the West of Boshrouyeh, East Central Iran

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Acta Geologica Sinica(English Edition) 2017年第5期91卷 1797-1819页

作者： Mahnaz SABBAGH BAJESTANI Asadollah MAHBOUBI Reza MOUSSAVI-HARAMI Ihsan AL-AASM Mehdi NADJAFI department of geology Faculty of Sciences Ferdowsi University of Mashhad department of Earth and environmental Sciences University of Windsor

The study area is located in the east Tabas Block in Central Iran. Facies analysis of the Qal＇eh Dokhtar Formation（middle Callovian to late Oxfordian） was carried out on two stratigraphic sections and applied to depositional environment and sequence stratigraphy interpretation. This formation conformably overlies and underlies the marly-silty Baghamshah and the calcareous Esfandiar formations, respectively. Lateral and vertical facies changes documents low-to high energy environments, including tidal-flat, beach to intertidal, lagoon, barrier, and open-marine. According to these facies associations and absence of resedimentation deposits a depositional model of a mixed carbonate-siliciclastic ramp was proposed for the Qal＇eh Dokhtar Formation. Seven third-order depositional sequences were identified in each two measured stratigraphic sections. Transgressive systems tracts（TSTs） show deepening upward trends, i.e. shallow water beach to intertidal and lagoonal facies, while highstand systems tracts（HST） show shallowing upward trends in which deep water facies are overlain by shallow water facies. All sequence boundaries（except at the base of the stratigraphic column） are of the no erosional（SB2） types. We conclude eustatic rather than tectonic factors played a dominant role in controlling carbonate depositional environments in the study area.

关键词： Sequence stratigraphy Qal9eh Dokhtar Formation mixed sUiciclastic-carbonate ramp Jurassic Central Iran

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A critical review of mineral-microbe interaction and co-evolution:mechanisms and applications

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National Science Review 2022年第10期9卷 209-229页

作者： Hailiang Dong Liuqin Huang Linduo Zhao Qiang Zeng Xiaolei Liu Yizhi Sheng Liang Shi Geng Wu Hongchen Jiang Fangru Li Li Zhang Dongyi Guo Gaoyuan Li Weiguo Hou Hongyu Chen Center for Geomicrobiology and Biogeochemistry Research State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences State Key Laboratory of Biogeology and environmental geology China University of Geosciences Illinois Sustainable Technology Center Illinois State Water Survey University of Illinois at Urbana-Champaign department of geology and environmental Earth Science Miami University

Mineral-microbe interactions play important roles in environmental change,biogeochemical cycling of elements and formation of ore *** provide both beneficial(physical and chemical protection,nutrients,and energy) and detrimental(toxic substances and oxidative pressure) effects to microbes,resulting in mineral-specific microbial *** impact dissolution,transformation and precipitation of minerals through their activity,resulting in either genetically controlled or metabolism-induced *** these interactions,minerals and microbes co-evolve through Earth ***-microbe interactions typically occur at microscopic scale but the effect is often manifested at global *** advances achieved through decades of research,major questions *** areas are identified for future research:integrating mineral and microbial ecology,establishing mineral biosignatures,linking laboratory mechanistic investigation to field observation,and manipulating mineral-microbe interactions for the benefit of humankind.

关键词： biomineralization co-evolution interactions microbe mineral nutrients

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