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Rift-associated ultramafic lamprophyre(damtjernite) from the middle part of the Lower Cretaceous(125 Ma) succession of Kutch,northwestern India: Tectonomagmatic implications

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Geoscience Frontiers 2018年第6期9卷 1883-1902页

作者： Rohit PANDey N.V.Chalapathi Rao Prashant Dhote Dinesh PANDit A.K.Choudhary Samarendra Sahoo B.Lehmann Electron Probe Micro Analyzer Laboratory Department of Geology Centre of Advanced Study Banaras Hindu University Bhumi Geoservices 1 & 2 Maa Bamleshwari Nagar Godhani Railway Institute Instrumentation Centre Indian Institute of Technology Mineral Resources Technical University of Clausthal

Mineralogical,geochemical and isotopic(Sr and Nd) studies on the recently reported ca. 124 Ma'anorogenic lamproite' dyke from the Palanpur area, Kutch seismogenic rift zone, northwestern India, are presented. We propose a new classification for the dyke as a damtjernite(ultramafic lamprophyre; UML)based on its porphyritic-panidiomorphic texture, abundance of phlogopite, presence of nepheline in the groundmass, and the composition of liquidus phases such as olivine, phlogopite, magnetite, and clinopyroxene(diopside). The Palanpur UML is primitive(Mg# =74-77),silica-undersaturated(SiO_2<40 wt.%),potassic to slightly sodic in nature, and is strikingly similar to the ～69 Ma UML dykes and sills of the Tethyan Indus suture zone, which are considered as the earliest yet known manifestations of the Deccan Large Igneous Province(LIP). Bulk-rock(^(87)Sr/^(86)Sr)_i(0.70460-0.70461) and ε_(N)d(t)(+2.56 to-0.69) of the Palanpur UML signify derivation from a slightly depleted mantle source similar to that of asthenospheric magmas such as OIB. This is further attested to by the high incompatible trace element ratios(viz., La/Ba, Nb/U, Nb/La and Ta/Yb) that are typical of plume-type magmas. However, the Neoproterozoic T_(DM) depleted mantle Nd model ages( ～655-919 Ma) also necessitate some involvement of a lithospheric mantle component in its genesis. High bulk-rock Fe_2 O_3~t and TiO_2 contents require the involvement of a fertile peridotitic mantle source, whereas high La/Yb(60-80) implies a control by residual garnet. Higher Rb/Sr and lower Ba/Rb suggest phlogopite as a residual phase and high Nb and lower La/Sm favour carbonatite, rather than silicate melt as metasomatising agent. Low degrees of partial melting of a primitive garnet lherzolite mantle can account for the observed REE patterns in the Palanpur UML. The Palanpur UML shares a temporal similarity to the Kerguelen plume-derived Rajmahal basalts and associated alkaline rocks from the eastern India. The tectonomagmatic

关键词： Tectonomagmatism Cretaceous Ultramafic lamprophyre Rift Kutch India

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Coping with the Impact of Climate Change: A Dive into Precision Agriculture in the United States

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Journal of Agricultural Chemistry and Environment 2024年第2期13卷 208-222页

作者： Oluwaseun Ibukun Kehinde Oke Olawale Oluwafemi department of geography and Planning University of Toledo Toledo USA Independent Researcher Manchester UK

With the continued increase in the number of people that are food insecure globally, which could be increasing because of the ongoing Ukraine-Russia war, leading to reduction in international agribusinesses, coupled with drastic climate change exacerbating the problem of food insecurity, there is a constant need to come up with innovative approaches to solve this global issue. In this article, we articulated how precision agriculture can be a tool for ensuring food security in the United States. This study aims to reiterate the significance of precision agriculture in solving global food insecurity.

关键词： United States Food Insecurity Precision Agriculture Positioning Systems Climate Change

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Modeled Surface Observations for Spatial Analysis of Landscape Dynamics

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Journal of Geographic Information System 2013年第4期5卷 409-417页

作者： Manoel do Couto Fernandes Tata Lacale Canal dos Santos Pedro Henrique Ferreira Coura Paulo Marcio Leal de Menezes Alan Jose Salomao Graca department of geography Federal University of Rio de JaneiroRio de JaneiroBrazil

Landscape dynamics is a geoecological characteristic that defines changes in a landscape spatial structure and function during an established time scale. In this kind of analysis, geoprocessing is an essential tool, because it combines several technologies that help in this work. However, the majority of landscape dynamic investigations do not consider the dimensionality of the data and the information to be used, which is projected not measured from modeled (real) surface observations, and presents underestimated results, mainly in irregular relief landscapes. Considering that, this paper intends to assess the difference between observations on modeled and planimetric surfaces on the interpretation of landscape dynamics. The study was conducted in the massif of Tijuca, Rio de Janeiro (Brazil) using land use and soil cover maps of different times and a digital elevation models (DEM) generated based on a triangular irregular. The results show an increase of dynamic areas values when observations were carried out on modeled surface, as well as the deforestation rate (17.57% or 0.13 km2/year). This survey showed higher values in comparison with observations on planimetric surface, characterizing more realistic interpretations of how the structural elements and analyses made from these are structured in the landscape.

关键词： DEM Modeled Surface Landscape Change

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Liquefaction structures induced by the M5.7 earthquake on May 28, 2018 in Songyuan, Jilin Province, NE China and research implication

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Journal of Palaeogeography 2020年第1期9卷 109-127页

作者： Zhu-Fu Shao Jian-Hua Zhong John Howell Bing Hao Xi-Wu Luan Ze-Xuan Liu Wei-Min Ran Yun-Feng Zhang Hong-Qi Yuan Jing-Jing Liu Liang-Tian Ni Guan-Xian Song Jin-Lin Liu Wen-Xin Zhang Bing Zhao School of Geosciences Northeast Petroleum UniversityDaqing 163318Heilongjiang ProvinceChina Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Mineral Shandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina department of geology and Petroleum Geolog University of AberdeenAberdeen AB243UEUK School of Geosciences China University of PetroleumQingdao 266580Shandong ProvinceChina Qingdao Institute of Marine geology China Geological SurveyQingdao 266071Shandong ProvinceChina.

An earthquake of magnitude M5.7 occurred in Yamutu village,Songyuan City,Jilin Province,NE China(45°16′12″N/124°42′35″E)on May 28,2018,with a focal depth of 13 *** epicenter is located at the intersection of the Fuyu/Songyuan-Zhaodong Fault,Second Songhua River Fault and Fuyu North Fault which lies northwest of TanchengLujiang Fault(Tan-Lu Fault).The earthquake-induced widespread liquefaction structures and ground surface fissures within 3 km from the epicenter,caused serious disasters to the local *** visible liquefied structures include sand volcanoes,liquefied sand mounds,sand dikes and sand *** volcanoes can be divided into sand volcano with a crater,sand volcano without a crater and water volcano(no sand).Other soft-sediment deformation structures(SSDS)induced by the earthquake include deformation lamination,load and flame structures,deformation folds,dish structures,convolute bedding and water-escape *** formation process of the sand volcanoes comprises three stages:(1)building up excess pore-fluid pressure in the liquefied layer,(2)cracking of the low-permeable overlying layer,and(3)mixture of sand-water venting out of the ground *** the upward movement,the liquefied sand is injected into the low-permeable layer to form sand veins,sand sills and various types of deformation *** distribution of seismic liquefaction structure can be divided into four zones:the thoroughly liquefied zone,the lower liquefied zone with SSDS,the upper liquefied zone with SSDS,and the ground surface liquefied *** liquefaction occurred at a burial depth of 2–5 m,and the thickness of liquefied sand is 2 ***-SW(35°–215°)trending compressive stress is possibly the seismogenic trigger of the Songyuan M5.7 earthquake that caused the fault(Fuyu/Songyuan-Zhaodong Fault)to *** study of the Songyuan seismic liquefaction structures gives insight into the prediction of modern earthquakes and disasterprone ***

关键词： Earthquake Soft-sediment deformation structures Liquefaction structure Sand volcano Songyuan

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Indigenous Land Management Practices and Land Cover Change in Akwa Ibom State, Nigeria

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Journal of Environmental Protection 2014年第16期5卷 1541-1552页

作者： Jacob Atser Ekong Faith Uwem Ituen Ekpa James department of Urban and Regional Planning University of Uyo Uyo Nigeria department of geography University of Uyo Uyo Nigeria

This work sought and identified the different types of land covers;detected the changes in land cover and examined the driving forces of such changes in Ibiono Ibom Local Government Area of Akwa Ibom State, Nigeria. Satellite images data of the area for 1986 and 2006 were collected for analysis. Household level social survey was conducted to generate data on the socio-economic variables. The images were subjected to principal component analysis to reduce and compress the data while the supervised image classification algorithm was applied to process the images into different land cover classes. The change detection algorithm in Erdas imagines was applied to measure and calculate the land cover change of the area. The result of the social survey revealed that 58% of the occupation was land based while in terms of yearly income, 65 percent earned less than $300 (#48000). The change detection carried out revealed an increase in areas of secondary forest while bush fallow recorded a reduction up to 34.02 hectares (56.55%) within the study period. Socio-economic variables of poor income and mode of land preparation for farming were the major drivers of change. Based on the findings, it is recommended that the slash and burn mode of land preparation be discouraged.

关键词： Indigenous Land Use Practices Land Cover Change Akwa Ibom State Nigeria

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Setting up a Spatial Data Infrastructure (SDI) for the ROSELT/OSS Network

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Journal of Geographic Information System 2014年第2期6卷 150-161页

作者： M. Ajmi M. H. Hamza M. Labiadh M. Yermani N. Ben Khatra A. S. Al-Thubaiti I. A. Moharrem A. El Arrim department of geography and Geographic Information Systems Faculty of Arts King Abdulaziz University Jeddah KSA department of geology Faculty of Science and Technology of Tangier Abdelmalek Essaadi University Tetuan Morocco Environment Programme Sahara and Sahel Observatory OSS Tunis Tunisia Geomatics Branch Environmental Design Faculty King Abdulaziz University Jeddah KSA Geomatics Earth and Land Settlement Branch Department of Geology Faculty of Sciences of Tunis Tunis El Manar University Tunis Tunisia

Environmental monitoring and evaluation (M&E) systems are indispensable tools for sustainable land management, especially in dry and fragile ecosystems. The reporting and dissemination of its products and indicators are the key roles to perform their missions. Furthermore, the overall success of such multilateral projects and networks depends on well-organized infrastructures for spatial data management. A spatial data infrastructure (SDI) is an efficient framework to centralize the management of spatial data and information related to multilateral projects for the best sharing and exchange between partners and stakeholders in order to ensure that they are interactively connected to use the data efficiently and in a flexible manner. This paper outlines the work undertaken in partnership between the geography and GIS department of the Faculty of Arts, King Abdulaziz University, Saudi Arabia Kingdom, the Geomatics, Earth and Land Settlement Branch of the department of geology, Faculty of Sciences of Tunis, Tunis El Manar University, Tunisia, and the Sahara and Sahel Observatory OSS which is an intergovernmental organization, in order to build a Spatial Data Infrastructure (SDI) for the ROSELT/OSS program (Long-Term Environmental Monitoring Observatories Network in the Circum-Sahara of the Sahara and Sahel Observatory). This SDI is entirely developed using Open Source technologies and the extensive suite of OGC (Open Geospatial Consortium) standards and specifications, to enable interoperability among and between its different components.

关键词： SDI Geospatial Data Metadata Geocatalogue Webmapping OGC

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Assessing the impacts of current and future changes of the planforms of river Brahmaputra on its land use-land cover

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Geoscience Frontiers 2023年第4期14卷 100-122页

作者： Jatan Debnath Dhrubajyoti Sahariah Durlov Lahon Nityaranjan Nath Kesar Chand Gowhar Meraj Pankaj Kumar Suraj Kumar Singh Shruti Kanga Majid Farooq department of geography Gauhati UniversityJalukbariAssamIndia GB Pant National Institute of Himalayan Environment(NIHE) Himachal Regional Centre(Himachal Pradesh)KulluIndia department of Ecology Environment and Remote SensingGovernment of Jammu and KashmirKashmir 190018India Institute for Global Environmental Strategies Hayama 240-0115Japan Centre for Sustainable Development Suresh Gyan Vihar UniversityJaipur 302017India Centre for Climate Change and Water Research(C3WR) Suresh Gyan Vihar UniversityJaipur 302017India department of geography School of Environment and Earth SciencesCentral University of PunjabVPO-GhuddaBathinda 151401India

River bankline migration is a frequent phenomenon in the river of the floodplain ***,channel dynamics-related changes in land use and land cover(LULC)are becoming a risk to the life and property of people living in the vicinity of rivers.A comprehensive evaluation of the causes and consequences of such changes is essential for better policy and decision-making for disaster risk reduction and *** present study assesses the changes in the Brahmaputra River planform using the GIS-based Digital Shoreline Analysis System(DSAS)and relates it with the changing LULC of the floodplain evaluated using the CA-Markov *** this study,the future channel of the Brahmaputra River and its flood plain’s future LULC were forecasted to pinpoint the erosion-vulnerable ***-eight years(1973–2021)of remotely sensed data were applied to estimate the rate of bankline *** was observed that the river’s erosion-accretion rate was higher in early times than in more recent *** left and right banks’average shifting rates between 1973 and 1988 were -55.44 m/y and -56.79 m/y,respectively,while they were-17.25 m/y and -48.49 m/y from 2011 to *** left bank of the river Brahmaputra had more erosion than the right,which indicates that the river is shifting in the leftward direction(Southward).In this river course,zone A(Lower course)and zone B(Middle course)were more adversely affected than zone C(Upper course).According to the predicted result,the left bank is more susceptible to bank erosion than the right bank(where the average rate of erosion and deposition was -72.23 m/y and 79.50 m/y,respectively).The left bank’s average rate of erosion was -111.22 m/*** research assesses the LULC study in conjunction with river channel dynamics in vulnerable areas where nearby infrastructure and settlements were at risk due to channel *** degree of accu-racy was verified using the actual bankline and predicted bankline,as well as the actual LULC map

关键词： Channel shifting Erosion-Accretion Bankline Prediction DSAS CA-Markov Brahmaputra River

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Research on Design and Management of Community-Based Ecotourism Model in Aksu-Zhabagly Nature Reserve of Kazakhstan

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Journal of Geoscience and Environment Protection 2022年第4期10卷 33-48页

作者： Imanaly Akbar Sholpan Abdreyeva Alexandr Artemyev Markhaba Тumazhanova Gulnar Orynbasarova department of Recreation geography and Tourism Al-Farabi Kazakh National University Almaty Kazakhstan

This study investigates the community-based ecotourism (CBE) model using a sample of the Aksu-Zhabagly nature reserve (NR). The aim is to propose a suitable CBE model for Aksu-Zhabgly nature-based tourism destinations by employing a combination of field observation, examination, evaluation, and SWOT analysis. The study determines the strategic suggestions for CBE model designing by the results of SWOT analysis. It concludes that convenient transportation and superior location, diversified wild animals and plants, rich in ethnocultural resources, traditional and tranquil life in a typical rural setting, hospitality and positive attitude of locals to tourism and great potential of the region for sustainable development of ecotourism are the strengths. At the same time, the far residential location from the provincial cities, low-quality service, outdated facilities and shortage of skilled employees in tourism management are the main weakness. Another group of constraints to tourism development is lack of tourism marketing and promotion agencies, lack of transparency, poor institution arrangement and corruption, and lack of preferential policies for CBE development. Finally, the paper recommends that economic development, environmental protection, culture and heritage, marketing and image, favorable political environment, and local residents’ empowerment are the main essential to effectively implement the sustainable development of CBE in the Aksu-Zhabagly tourist destination.

关键词： Management Community-Based Ecotourism Model Aksu-Zhabagly Nature Reserve Kazakhstan

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Graph theoretical analysis of limestone fracture network damage patterns based on uniaxial compression test

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3485-3510页

作者： Mingyang Wang Congcong Wang Enzhi Wang Xiaoli Liu Xiao Li State Key Laboratory of Hydro-science and Engineering Tsinghua UniversityBeijing100084China department of Automation Tsinghua UniversityBeijing100084China Beijing Huairou Laboratory Beijing101400China Institute of geology and Geophysics Chinese Academy of ScienceBeijing100029China

The topological attributes of fracture networks in limestone,subject to intense hydrodynamics and intricate geological discontinuities,substantially influence the mechanical and hydraulic characteristics of the rock *** dynamical evolution of fracture networks under stress is crucial for unveiling the interaction patterns among ***,existing models are undirected graphs focused on stationary topology,which need optimization to depict fractures'dynamic development and rupture *** compensate for the time and destruction terms,we propose the damage network model,which defines the physical interpretation of fractures through the ternary *** focus primarily on the evolution of node types,topological attributes,and motifs of the fracture network in limestone under uniaxial *** expose the varying behavior of the nodes'self-dynamics and neighbors'adjacent dynamics in the fracture *** approach elucidates the impact of micro-crack behaviors on large brittle shear fractures from a topological perspective and further subdivides the progressive failure stage into four distinct phases(isolated crack growth phase,crack splay phase,damage coalescence phase,and mechanical failure phase)based on the significance profile of the *** analysis reveals a positive linear and negative power correlation between fracture network density and branch number to the rock damage resistance,*** damage network model introduces a novel methodology for depicting the interaction of two-dimensional(2D)projected fractures,considering the dynamic spatiotemporal development characteristics and fracture geometric *** helps dynamically characterize properties such as connectivity,permeability,and damage factors while comprehensively assessing damage in rock mass fracture networks.

关键词： Motif Fracture network Topological property Damage resistance Limestone

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The Pushtashan juvenile suprasubduction zone assemblage of Kurdistan (northeastern Iraq): A Cretaceous (Cenomanian) Neo-Tethys missing link

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Geoscience Frontiers 2017年第5期8卷 1073-1087页

作者： Sabah A.Ismail Sarmad A.Ali Allen P.Nutman Vickie C.Bennett Brain G.Jones department of Applied geology College of Sciences Kirkuk University Kirkuk 36001 Iraq GeoQuEST Research Centre School of Earth & Environmental Sciences University of Wollongong Wollongong NSW 2522 Australia Research School of Earth Sciences Australian National University ACT 0200 Australia

The Pushtashan suprasubduction zone assemblage of volcanic rocks, gabbros, norites and peridotites occurs in the Zagros suture zone, Kurdistan region, northeastern Iraq. Volcanic rocks are dominant in the assemblage and consist mainly of basalt and basaltic andesite flows with interlayered red shale and limestone horizons. Earlier lavas tend to be MORB-like, whereas later lavas display island arc tholeiite to boninitic geochemical characteristics. Tholeiitic gabbros intrude the norites and display fractionation trends typical of crystallisation under low-pressure conditions, whereas the norites display calc-alkaline traits, suggesting their source included mantle metasomatised by fluids released from subducted oceanic crust. Enrichment of Rb, Ba, Sr, Th and the presence of negative Nb anomalies indicate generation in a suprasubduction zone setting. Trondhjemite and granodiorite intrusions are present in the volcanic rocks, gabbros and norites. SHRIMP U-Pb dating of magmatic zircons from a granodiorite yields a mean^(206)Pb/^(238)U age of 96.0 ±2.0 Ma(Cenomanian). The initial ε_(Hf) value for the zircons show a narrow range from +12.8 to+15.6, with a weighted mean of + 13.90±0.96. This initial value is within error of model depleted mantle at 96 Ma or slightly below that, in the field of arc rocks with minimal contamination by older continental crust. The compositional bimodality of the Pushtashan suprasubduction sequence suggests seafloor spreading during the initiation of subduction, with a lava stratigraphy from earlyerupted MORB transitioning into calc-alkaline lavas and finally by 96 Ma intrusion of granodioritic and trondhjemitic bodies with juvenile crustal isotopic signatures. The results confirm another Cretaceous arc remnant preserved as an allochthon within the Iraqi segment of the Cenozoic Zagros suture zone. Implications for the closure of Neo-Tethys are discussed.

关键词： Pushtashan suprasubduction assemblage Cretaceous Zircon U-Pb dating Hf isotopes Kurdistan region lraq Neo-Terhys

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