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Remote estimates of suspended particulate matter in global lakes using machine learning models

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International Soil and Water Conservation Research 2024年第1期12卷 200-216页

作者： Zhidan Wen Qiang Wang Yue Ma Pierre Andre Jacinthe Ge Liu Sijia Li Yingxin Shang Hui Tao Chong Fang Lili Lyu Baohua Zhang Kaishan Song Northeast Institute of geography and Agroecology CASChangchunJilin130102China department of geology Indiana University∼Purdue UniversityIndianapolisIN44602USA University of Chinese Academy of Sciences Beijing100100China College of geography and Urban Planning Liaocheng UniversityLiaochengChina

Suspended particulate matter(SPM)in lakes exerts strong impact on light propagation,aquatic ecosystem productivity,which co-varies with nutrients,heavy metal and micro-pollutant in *** lakes,SPM exerts strong absorption and backscattering,ultimately affects water leaving signals that can be detected by satellite *** regression models based on specific band or hand ratios have been widely used for SPM estimate in the past with moderate *** are still rooms for model accuracy improvements,and machine learning models may solve the non-linear relationships between spectral variable and SPM in *** assembled more than 16,400 in situ measured SPM in lakes from six continents(excluding the Antarctica continent),of which 9640 samples were matched with Landsat overpasses within±7 *** machine learning algorithms and two simple regression methods(linear and partial least squares models)were used to estimate SPM in lakes and the performance were *** overcome the problem of imbalance datasets in regression,a Synthetic Minority Over-Sampling technique for regression with Gaussian Noise(SMOGN)was adopted in this *** comparison,we found that gradient boosting decision tree(GBDT),random forest(RF),and extreme gradient boosting(XGBoost)models demonstrated good spatiotemporal transferability with SMOGN processed dataset,and has potential to map SPM at different year with good quality of Landsat land surface reflectance *** all the tested modeling approaches,the GBDT model has accurate calibration(n=6428,R^(2)=0.95,MAPE=29.8%)from SPM collected in 2235 lakes across the world,and the validation(n=3214,R^(2)=0.84,MAPE=38.8%)also exhibited stable ***,the good performances were also exhibited by RF model with calibration(R^(2)=0.93)and validation(R^(2)=0.86,MAPE=24.2%)*** applied GBDT and RF models to map SPM of typical lakes,and satisfactory result was *** addition,the GBDT model was evaluated b

关键词： Landsat imagery Remote estimation SPM Transferability

Mineralogy and whole-rock geochemistry of the Oligocene Barail Group of rocks of Belt of Schuppen,Northeast India:Implications for tectono-provenance and paleo-weathering

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Acta Geochimica 2024年第5期43卷 904-932页

作者： Manash Pratim Gogoi Yunpeng Dong Pradip Borgohain Devojit Bezbaruah Arvind Pandey Yadav Krishna Gogoi Garima Konwar Gautam Raj Bawri Bubul Bharali department of Petroleum Technology Dibrugarh UniversityAssam 786004India department of geology Northwest UniversityXi’an 710069China department of Applied geology Dibrugarh UniversityAssam 786004India department of Statistics Central University of RajasthanAjmer 305817India department of geology Mizoram UniversityAizawlMizoram 796004India department of geology Pachhunga University CollegeAizawlMizoram 796001India

The petrographic and geochemical attributes of the Oligocene Barail Group of rocks are used to decipher the likely source area(s)or tectonic domains,as this sequence of rocks was deposited in a foreland basin governed by orogenic domain,namely the North-east Arunachal *** river system that gave rise to the Brahmaputra River(Yarlung-Tsangpo),which flowed through several tectonic domains of the Himalayan ranges,primarily from BomiChayu,Gangadese Granitoid,Higher Himalayan Leucogranites,and Namche Barwa into the proto Bengal Basin now a part of Assam Arakan Basin and Naga Schuppen Belt,was the main source of the sandstone formation of the Barail *** purpose of sandstone petrography,which combines modal analysis with XRF(Major Oxides)and HR-ICPMS(Trace&Rare Earth Elements)research,is to identify the type of source rock(s),their weathering pattern,and its paleo-environmental *** sandstones were formed from recycled orogen and include lithic and sublithic arenite variants with advanced texture and chemical *** sediments were felsic(Th/Co:1.38,Cr/Th:9.78,La/Lu:11.58,Th/Sc:0.99,Eu/Eu*:0.66,La/Sc:3.05,La/Co:4.18),with contributions from intermediate source rocks and low-rank metamorphics deposited in an active continental margin to a continental island arc *** conditions impacted the sediments of Barails,characterised by being warm and semi-humid to humid which resulted in moderate to a high degree of chemical weathering,as shown by weathering indices like CIA(79.14),PIA(85.47),CIW(86.9),WIP(32.50),ICV(0.71),and Th/U(6.03),which were further additionally supported by C-Value(1.01),PF(1.20),Sr/Cu(2.04),and Rb/Sr(0.97).

关键词： Belt of Schuppen Barail Group Sandstone Petrography Geochemistry Provenance Tectonic setting

Interdecadal variation of drought patterns and associated influencing factors in the north-south transitional zone of China

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Journal of Geographical Sciences 2024年第7期34卷 1253-1279页

作者： DONG Qingdong ZHU Lianqi DUAN Zheng WANG Liyuan CHEN Chaonan LI Yanhong ZHU Wenbo GURUNG Sher Bahadur The College of geography and Environmental Science Henan UniversityKaifengHenan475004China department of Physical geography and Ecosystem Science Lund UniversityLundS-22362Sweden Central department of geography Tribhuvan UniversityKathmandu44600Nepal

In the context of global warming,escalating water cycles have led to a surge in drought frequency and ***,multidecadal fluctuations in drought and their multifaceted influencing factors remain inadequately *** study examined the multidecadal changes in drought characteristics(frequency,duration,and severity)and their geographical focal points within China's north-south transitional zone,the Qinling-Daba Mountains(QDM),from 1960 to 2017 using the Standardized Precipitation Evapotranspiration Index(SPEI).In addition,a suite of eight scenarios,correlation analysis,and wavelet coherence were used to identify the meteorological and circulation factors that influenced drought *** results indicate the following:(1)From 1960 to 2017,the QDM experienced significant interdecadal variations in drought frequency,duration,and severity,the climate was relatively humid before the 1990s,but drought intensified ***,the 1990s marked the period of the longest drought duration and greatest severity,while the years spanning 2010 to 2017 experienced the highest frequency of drought events.(2)Spatially,the Qinling Mountains,particularly the western Qinling Mountain,exhibited higher drought frequency,duration,and severity than the Daba *** disparity can be attributed to higher rates of temperature increase and precipitation decrease in the western Qinling Mountain.(3)Interdecadal variations in droughts in the QDM were directly influenced by the synergistic effects of interdecadal fluctuations in air temperature and *** factors modulate temperature and precipitation through phase transitions,thereby affecting drought dynamics in the *** Atlantic Multidecadal Oscillation emerges as the primary circulation factors influencing temperature changes,with a mid-1990s shift to a positive phase favoring *** East Asian Summer Monsoon and El Ni?o-Southern Oscillation are the main circulation factors a

关键词： drought standardized precipitation evapotranspiration index multidecadal shift transitional zone Qinling-Daba Mountains

Mineralogy and geochemistry of trachytic rocks from the Lichi Volcanics, Eastern Himalaya: insights into the Kerguelen mantle plume activity in the Eastern Himalayan Region

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Acta Geochimica 2024年第1期43卷 180-197页

作者： Pallabi Basumatary Deepshikha Borah Hiredya Chauhan Tribujjal Prakash Bibhuti Gogoi department of geology Cotton UniversityGuwahatiAssam 781001India Wadia Institute of Himalayan geology DehradunUttarakhand 248001India

The Lichi volcanics are a suite of mafic-intermediate-felsic rocks and are considered coeval with the Abor volcanics(~132 Ma) of the Siang window in the Eastern Himalaya. Here, we present the first report of trachytic rocks from the Lichi volcanics, which are exposed in the Ranga valley, along the Kimin-Yazali road section in the Eastern Himalayan Region, Northeast India. The trachytes occur in close association with sandstones of the Gondwana Group of rocks and are characterised based on field, petrographical, and geochemical *** fine-grained trachytes are composed of alkali feldspar, biotite, plagioclase, sodic-amphibole, apatite, illmenite, and titanite. The REE profiles of the evolved trachytic rocks(higher SiO_(2)content) display fractionated trends. The fractionation of accessory mineral phases, like apatite and titanite, was possibly responsible for the strongly fractionated REE patterns of the evolved *** trachytic rocks demonstrate high apatite saturation temperatures of 988 ± 14 ℃(1σ, n = 8). The Aluminium Saturation Index(< 1.1) and binary discrimination diagrams of these peralkaline trachytes define their affinity with A-type granitoids. Elemental ratios like Y/Nb, Nb/U,and Ce/Pb signify that the Lichi trachytes are differentiated products of mantle-derived ocean island basalts. Trace elemental discrimination diagrams Th/Yb versus Nb/Yb, Y versus Nb, and Y + Nb versus Rb reflect a within-plate tectonic regime for the trachytes. From the results presented in this work, we infer that the development of rifting events during the breakup of eastern Gondwana due to the onset of Kerguelen plume activity further led to underplating of basic magma in lower crustal levels. These parental basaltic magmas underwent fractionation processes forming differentiated trachyandesites and *** into consideration the similarities recorded between the Lichi volcanics and Abor volcanics, this study supports the idea that Kerguelen plume ac

关键词： Peralkaline trachytes Trachyandesites A-type granitoids Apatite saturation temperature Abor volcanics Eastern Gondwana

Basin Analysis and Paleogeography of the Zagros Foreland Basin during the Maastrichtian, High Zagros Basin, Iran

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Journal of Earth Science 2024年第5期35卷 1527-1545页

作者： Hossein Ghanbarloo Amrollah Safari department of geology University of Isfahan

A sedimentological investigation was carried out to reconstruct the paleogeography of the Zagros Foreland Basin. Based on the study of more than 1 000 rock samples, nine carbonate microfacies and three terrigenous facies were identified. The study reveals that the Maastrichtian succession was deposited in a widespread homoclinal ramp in the High Zagros Basin. Three(Gandom Kar area), two(Ardal area), seven(Gardbishe area), five(Shirmard area), two(Kuh-e-Kamaneh area), three(Kuh-e-Balghar area), and six(Murak area) of depositional sequences(3rd order) were identified. The thickness of the lowstand systems tract(LST) due to activities of local faults and subsidence in the southeast is more than in the central and northwest of the High Zagros Basin during the Early and Early Middle Maastrichtian. During the Middle Maastrichtian, the shallow and deep marine deposits were formed during the transgressive systems tract(TST) and highstand systems tract(HST) in this basin and the rate of subsidence in the center of this basin(Gardbishe area) is higher than in other areas and the platform was drowned in this area. The falling relative sea-level due to activities of local faults led to that marine deposits were absent in all parts of the High Zagros Basin(except the south part) during the Late Maastrichtian. Paleogeographical studies on the Zagros Basin during the Late Campanian-Maastrichtian showed the following results: shallow marine environments were developed in the southeast of this basin, and the turbidite, delta, and fluvial environments in the northwest were developed more than in other areas.

关键词： Maastrichtian deposits local fault depositional sequences Neotethys Basin Inception Foreland Basin Late Cretaceous basin analysis paleogeography

Sedimentological evidence of climate-tectonic interaction in the upper Satluj catchment of NW Himalaya

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Journal of Mountain Science 2024年第6期21卷 1978-1991页

作者： JOSHI Moulishree JALAL Poonam department of geology Kumaun UniversityNainitalUttarakhand 263001India

Quaternary valley fill deposits in the Upper Satluj Valley of NW Himalaya act as archives of changing climate-tectonic dynamics in a *** landforms help in decoding the relationship between climate and *** region is traversed by several active faults and thrusts such as the Kaurik-Chango Fault(KCF)and Sangla Detachment(SD),thereby making upper Satluj Valley tectonically *** parameters such as width of valley floor(Vfw),Normalized Steepness Index(KSn)and geomorphological evidences such as the presence of huge strath terraces,narrowing of the river valley and palaeolake deposits point towards the tectonically active nature of the *** arid,high elevation region is also climatically sensitive as it falls in a transient climatic zone which receives rainfall only during abnormal monsoon *** rainfall causes outburst floods,a common phenomenon in the area due to the blocking of headwater in the upper reaches of the Satluj *** a result,the Quaternary sequence is modified from time to *** transition from hypo concentrated deposits to channel deposits and ponding events are prominent in the depositional sequence,resulting from a response to *** studied Quaternary sediments reveal that the Trans-Himalayan region of the upper Satluj valley is affected by tectonic-climate variability,making it vulnerable to geohazards.

关键词： Himachal Pradesh Quaternary Lithofacies association Tectonics Climate

Morphology of crater and caldera lakes in the Far Eastern region of Russia and the features of their development

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Journal of Mountain Science 2024年第4期21卷 1246-1258页

作者： Dmitrii N.KOZLOV Ekaterina V.LEBEDEVA Institute of Marine geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia Institute of geography Russian Academy of SciencesMoscow 119017Russia

Volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data *** authors have conducted a study of 10 lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 15 lakes in the region,calculating their main morphometric *** has been established that many caldera lake basins are modified by young explosive funnels,extrusive or effusive domes,and exhibit traces of hydrothermal *** lakes of the same genetic type in the Kuril-Kamchatka region are similar in depth and depression forms,the group of caldera lakes shows less homogeneity across all morphometric *** was found that the absolute heights of the reservoirs on Kamchatka Peninsula are generally greater than those on the Kuril Islands,as is often the case with the size of their *** volcanic lakes under study can rapidly change their volume and shape under the influence of endogenous *** the first time for this region,on the base of repeated observations,underwater extrusive dome rate growth and the approximate rates of 2 lake level changes were *** observations of lakes in the Ksudach calderas(Kamchatka)and on Simushir Island indicate approximate rates of level changes:a decrease ranging within 0.5-0.6 m per year(over a 27-year observation interval)and an increase reaching up to 0.26 m per year(over a 48-year interval).The growth rate of the underwater extrusive dome in Lake Shtyubel has averaged 1-1.6 m per year over the past 25 *** analysis has facilitated the first generalization regarding the morphology and developmental features of crater and caldera lakes in the Kuril-Kamchatka region of Russia,representing an important step in their *** results obtained will provide a solid foundation for subsequent research in this region and may be of interest to researchers studying

关键词： Volcanic lakes Echolocation survey Volcanism Gashydrotherms Kamchatka Kuril Islands

Geochemistry of island arc assemblage in the Eastern Desert of Egypt and the role of Pan-African magmatism in crustal growth of the Arabian–Nubian Shield:A review

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Acta Geochimica 2024年第3期43卷 588-622页

作者： Abdel-Aal MAbdel-Karim Mohamed MHamdy Adel A.Surour geology department Faculty of ScienceZagazig UniversityZagazig 44519Egypt geology department Faculty of ScienceTanta UniversityTanta 31527Egypt department of Geological Sciences Faculty of ScienceNew Galala City 43511Egypt geology department Faculty of ScienceCairo UniversityGiza 12613Egypt

Neoproterozoic island arc assemblage of the Arabian–Nubian Shield(ANS)in the Eastern Desert(ED)of Egypt comprises juvenile suites of metavolcanics(MV),large amounts of meta-sedimentary rocks(MS),and voluminous metagabbros-diorites(MGD)and syn-tectonic intrusions of older granitoids(OG).We report here the updates of these four rock units in terms of classification,distribution,chemical characteristics,geodynamic evolution,metamorphism,and *** addition,we discuss these integrated data to elucidate a reasonable and reliable model for crustal evolution in the *** main features of these rock units indicate their relation to each other and the geodynamic environment dominated by early immature oceanic island arcs to primitive continental *** information of the island arc metavolcanic and plutonic rocks(gabbros,diorites,tonalites,and granodiorites)furnish evidence of the genetic *** include proximity and a coeval nature in the field;all protolith magmas are subalkaline in nature following calc-alkaline series with minor tholeiitic affinities;common geochemical signature of the arc rocks and subduction-related magmatism;their similar enrichment in LREEs;and similar major element compositions with mafic melts derived from metasomatized mantle *** volcano-sedimentary and the OG rocks underwent multiphase deformation events whereas the MGD complexes deformed *** on the magmatic,sedimentological,and metamorphic evolutions constrained by geochronological data as well as the progressive evolutionary trend from extensional to compressional regimes,a possible gradual decrease in the subducted slab dip angle is the most infl uential in any geodynamic model for arc assemblage in the ED of Egypt.

关键词： Island arc assemblage Magmatism Crustal growth Neoproterozoic Arabian–Nubian Shield Eastern Desert Egypt

Establishing the relationship between land use land cover,normalized difference vegetation index and land surface temperature:A case of Lower Son River Basin,India

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geography and Sustainability 2024年第2期5卷 265-275页

作者： Shipra Singh Pankaj Kumar Rakhi Parijat Barbaros Gonengcil Abhinav Rai department of geography Miranda HouseUniversity of DelhiDelhiIndia department of geography Delhi School of EconomicsUniversity of DelhiDelhiIndia department of geography Istanbul UniversityIstanbulTurkey

The study explores the intricate interplay between land use land cover(LULC),normalized difference vegetation index(NDVI),and land surface temperature(LST)within the Lower Son River Basin in India from 1991 to *** region’s ecological balance has been increasingly strained due to rapid urbanization and changing land use *** a combination of Landsat TM&OLI/TIRS satellite imageries and geospatial analysis techniques,this study unveils the intricate connection between land use and land cover changes,vegetation,and land surface temperature *** study area is classified into three altitudinal zones(Zone Ⅰ:39–300 m,Zone Ⅱ:301–600 m and Zone Ⅲ:601–1,247 m)to examine the changes in *** area has seen significant changes in LULC,vegetation and LST in all the three altitudinal *** findings hold significant implications for sustainable land management and environmental conservation strategies in the Lower Son River *** per the result,103,438 ha of vegetation was converted into agriculture land and 82,572 ha of agricultural land was transformed into settlements from 1991 to *** trend shows human pressure on the land resource in the study *** increase in water body is seen which is attributed to commissioning of Bansagar *** Ⅰ has seen highest settlement growth while Zone Ⅲ experienced severe deforestation of around 15%.Zone Ⅱ and Ⅲ needs attention for holistic *** of LST shows that it has increased by 0.82℃ from 1991 to 2020 which is a red *** study underscores the critical importance of balanced land use practices to preserve ecological integrity and mitigate the adverse effects of urbanization and climate change.

关键词： Lower Son River Basin LULC LST NDVI Correlation