The seismically active Ka-Ping Block within Xinjiang, China, represents a zone of potential earthquake hazards, and existing surface measurements cannot fully reflect the area’s sub-surface slip rates. To determine these slip rates and characterize the level of hazard that the study area may face in future years, using a cross-correlation of waveforms, we identified 432 repeat sequences along large faults (F1–F5) in the Ka-Ping Block between September 2009 and April 2022 and computed the annual slip rate for every sequence with the empirical relationship of the moment and the seismic magnitude. Spatial distribution images and temporal evolution characteristics of deep deformation in fault zones were constructed. We obtained five asperities in the Ka-Ping Block, the western portion of the PiQiang fault (F4) had a larger yearly slide rate than its eastern portion, and the southwest and eastern areas of the KEP station show an elevated risk of seismic activity within the next two years.
{"title":"Deep fault sliding rates for Ka-Ping block of Xinjiang based on repeating earthquakes","authors":"Chaojun Gao, Daiqin Liu, Jie Li, Chunyan Song, Gulizinati Yideresi, Ailixiati Yushan","doi":"10.1515/geo-2022-0610","DOIUrl":"https://doi.org/10.1515/geo-2022-0610","url":null,"abstract":"The seismically active Ka-Ping Block within Xinjiang, China, represents a zone of potential earthquake hazards, and existing surface measurements cannot fully reflect the area’s sub-surface slip rates. To determine these slip rates and characterize the level of hazard that the study area may face in future years, using a cross-correlation of waveforms, we identified 432 repeat sequences along large faults (F1–F5) in the Ka-Ping Block between September 2009 and April 2022 and computed the annual slip rate for every sequence with the empirical relationship of the moment and the seismic magnitude. Spatial distribution images and temporal evolution characteristics of deep deformation in fault zones were constructed. We obtained five asperities in the Ka-Ping Block, the western portion of the PiQiang fault (F4) had a larger yearly slide rate than its eastern portion, and the southwest and eastern areas of the KEP station show an elevated risk of seismic activity within the next two years.","PeriodicalId":48712,"journal":{"name":"Open Geosciences","volume":"3 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140017807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Based on land use classification data for the Yangtze River Delta region in 2000, 2015, and 2020, this study aims to explore the spatial and temporal evolution of ecosystem services value (ESV) in the region. By analyzing the land use structure and its dynamic changes, an ESV model is constructed. Furthermore, the study utilizes a geodetector to analyze the driving factors of ESV in the Yangtze River Delta region. The findings are as follows: (1) From 2000 to 2020, arable land was the predominant land use type in the Yangtze River Delta region. (2) The ESV in the region showed an upward trend followed by a decline from 2000 to 2020. Regulating services and supporting services have always been the core functions of ecosystem services in the region, with hydrological regulation contributing the most. (3) From a spatial perspective, there were significant differences in the spatial distribution of AESV (aggregated ecosystem services value) in the Yangtze River Delta region. The AESV changes in various cities within the region were evident, with a decreasing trend observed in most cities. (4) The sensitivity index of each land use type was less than 1, with forest land exhibiting the highest sensitivity and having the greatest impact on ESV. (5) Geodetector analysis revealed that the AESV in the Yangtze River Delta region is influenced by a combination of regional natural factors, economic factors, and social factors, and the interaction among different driving forces significantly enhances the spatial heterogeneity of AESV in the region.
{"title":"Spatial and temporal changes in ecosystem services value and analysis of driving factors in the Yangtze River Delta Region","authors":"Wei Zhang, Fang-Fang Wang, Wei Shan","doi":"10.1515/geo-2022-0604","DOIUrl":"https://doi.org/10.1515/geo-2022-0604","url":null,"abstract":"Based on land use classification data for the Yangtze River Delta region in 2000, 2015, and 2020, this study aims to explore the spatial and temporal evolution of ecosystem services value (ESV) in the region. By analyzing the land use structure and its dynamic changes, an ESV model is constructed. Furthermore, the study utilizes a geodetector to analyze the driving factors of ESV in the Yangtze River Delta region. The findings are as follows: (1) From 2000 to 2020, arable land was the predominant land use type in the Yangtze River Delta region. (2) The ESV in the region showed an upward trend followed by a decline from 2000 to 2020. Regulating services and supporting services have always been the core functions of ecosystem services in the region, with hydrological regulation contributing the most. (3) From a spatial perspective, there were significant differences in the spatial distribution of AESV (aggregated ecosystem services value) in the Yangtze River Delta region. The AESV changes in various cities within the region were evident, with a decreasing trend observed in most cities. (4) The sensitivity index of each land use type was less than 1, with forest land exhibiting the highest sensitivity and having the greatest impact on ESV. (5) Geodetector analysis revealed that the AESV in the Yangtze River Delta region is influenced by a combination of regional natural factors, economic factors, and social factors, and the interaction among different driving forces significantly enhances the spatial heterogeneity of AESV in the region.","PeriodicalId":48712,"journal":{"name":"Open Geosciences","volume":"17 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140017806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This article proposes random forest algorithm (RFA), multi-layer perception (MLP) artificial neural network (ANN), and support vector machine (SVM) method for classifying the fused data of Sentinel-2, Landsat-8, and Airbus Vision-1 satellites for the years 2016 and 2023. The first variant of fusion is performed for Sentinel-2 and Landsat-8 data to sharpen it to 10 m spatial resolution, while in the second case, Sentinel-2 and Airbus Vision-1 data are fused together to achieve a spatial resolution of 3.48 m. MLP-ANN, SVM, and RFA methods are applied to the sharpened dataset for the years 2023 and 2016 having spatial resolutions of 3.48 and 10 m, respectively, and a detailed comparative analysis is performed. Google earth engine is utilized for ground data validation of the classified samples. An enhanced convergence time of 100 iterations was achieved using MLP-ANN for the classification of the dataset at 3.48 m spatial resolution, while the same method took 300 iterations with the dataset at 10 m spatial resolution to achieve a minimum limit Kappa hat score of 0.85. With 10 m spatial resolution, the MLP-ANN achieved an overall accuracy of 96.6% and a Kappa hat score of 0.94, while at 3.48 m spatial resolution, the aforementioned scores are enhanced to 98.5% and 0.97, respectively. Similarly, with 10 m spatial resolution, the RFA achieved an overall accuracy of 92.6% and a Kappa hat score of 0.88, while at 3.48 m spatial resolution, the abovementioned scores are enhanced to 96.5 and 0.95% respectively. In view of the forgoing, the MLP-ANN showed better performance as compared to the RFA method.
{"title":"Random forest and artificial neural network-based tsunami forests classification using data fusion of Sentinel-2 and Airbus Vision-1 satellites: A case study of Garhi Chandan, Pakistan","authors":"Shabnam Mateen, Narissara Nuthammachot, Kuaanan Techato","doi":"10.1515/geo-2022-0595","DOIUrl":"https://doi.org/10.1515/geo-2022-0595","url":null,"abstract":"This article proposes random forest algorithm (RFA), multi-layer perception (MLP) artificial neural network (ANN), and support vector machine (SVM) method for classifying the fused data of Sentinel-2, Landsat-8, and Airbus Vision-1 satellites for the years 2016 and 2023. The first variant of fusion is performed for Sentinel-2 and Landsat-8 data to sharpen it to 10 m spatial resolution, while in the second case, Sentinel-2 and Airbus Vision-1 data are fused together to achieve a spatial resolution of 3.48 m. MLP-ANN, SVM, and RFA methods are applied to the sharpened dataset for the years 2023 and 2016 having spatial resolutions of 3.48 and 10 m, respectively, and a detailed comparative analysis is performed. Google earth engine is utilized for ground data validation of the classified samples. An enhanced convergence time of 100 iterations was achieved using MLP-ANN for the classification of the dataset at 3.48 m spatial resolution, while the same method took 300 iterations with the dataset at 10 m spatial resolution to achieve a minimum limit Kappa hat score of 0.85. With 10 m spatial resolution, the MLP-ANN achieved an overall accuracy of 96.6% and a Kappa hat score of 0.94, while at 3.48 m spatial resolution, the aforementioned scores are enhanced to 98.5% and 0.97, respectively. Similarly, with 10 m spatial resolution, the RFA achieved an overall accuracy of 92.6% and a Kappa hat score of 0.88, while at 3.48 m spatial resolution, the abovementioned scores are enhanced to 96.5 and 0.95% respectively. In view of the forgoing, the MLP-ANN showed better performance as compared to the RFA method.","PeriodicalId":48712,"journal":{"name":"Open Geosciences","volume":"6 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139952549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yang Wang, Youyang You, Jinyu Huang, Xiaoli Yue, Guiquan Sun
Exploring the pattern of block vitality within cities and its influencing factors is an important topic in urban vitality research, which has great significance in promoting high-quality urban development. However, existing research has paid little attention to the spatial difference characteristics of daytime and night urban vitality and the differences in their influencing factors. Using the urban area of Kunming, China, as a case study, this study explores the differences in spatial patterns of daytime and night vitality at the intra-city block scale and analyses the differences in the main influencing factors of daytime and night block vitality using spatial regression models. The study obtains the following findings: (1) daytime block vitality in Kunming’s urban district (the urban Dist. of KM) is higher than night block vitality. The First Ring Area has the highest daytime block vitality, whereas the Second Ring Area has the highest night block vitality. (2) Block vitality in the urban Dist. of KM presents a polycentric structure. (3) There are obvious differences in the factors influencing urban vitality between daytime and night, with work accessibility, functional mixing, daily consumption accessibility, floor area ratio, and average building age, having different directions of influence on daytime and night urban vitality. (4) Daytime urban vitality in the urban Dist. of KM relies on work activities, while night urban vitality relies on residential activities. The results provide a scientific basis for urban land use layout, facility construction, and higher-quality urban planning and management, thus promoting sustainable urban development.
{"title":"Differences in urban daytime and night block vitality based on mobile phone signaling data: A case study of Kunming’s urban district","authors":"Yang Wang, Youyang You, Jinyu Huang, Xiaoli Yue, Guiquan Sun","doi":"10.1515/geo-2022-0596","DOIUrl":"https://doi.org/10.1515/geo-2022-0596","url":null,"abstract":"Exploring the pattern of block vitality within cities and its influencing factors is an important topic in urban vitality research, which has great significance in promoting high-quality urban development. However, existing research has paid little attention to the spatial difference characteristics of daytime and night urban vitality and the differences in their influencing factors. Using the urban area of Kunming, China, as a case study, this study explores the differences in spatial patterns of daytime and night vitality at the intra-city block scale and analyses the differences in the main influencing factors of daytime and night block vitality using spatial regression models. The study obtains the following findings: (1) daytime block vitality in Kunming’s urban district (the urban Dist. of KM) is higher than night block vitality. The First Ring Area has the highest daytime block vitality, whereas the Second Ring Area has the highest night block vitality. (2) Block vitality in the urban Dist. of KM presents a polycentric structure. (3) There are obvious differences in the factors influencing urban vitality between daytime and night, with work accessibility, functional mixing, daily consumption accessibility, floor area ratio, and average building age, having different directions of influence on daytime and night urban vitality. (4) Daytime urban vitality in the urban Dist. of KM relies on work activities, while night urban vitality relies on residential activities. The results provide a scientific basis for urban land use layout, facility construction, and higher-quality urban planning and management, thus promoting sustainable urban development.","PeriodicalId":48712,"journal":{"name":"Open Geosciences","volume":"50 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139952603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frequent magmatic intrusion and eruption during the early Yanshanian in South China formed a unique and diverse igneous rock assemblage, mainly comprising granite, rhyolite, and some basic rocks. Nevertheless, the tectonic regime responsible for the formation of these granitic rocks remains controversial. The comprehensive available data suggest that the Jurassic granitic rocks formed during the period from 180 to 145 Ma, with an age peak at ca. 160 Ma. Jurassic rocks are predominantly concentrated in Wuyi, southern Hunan, northeast Guangdong, and southern Jiangxi, followed by the eastern Guangxi-western Guangdong areas, mainly including I-, S-, and A-type granites, and a few I–S transformation-type granites. These granitic rocks invariably exhibit enrichment in Rb, Th, U, and Pb, while Ba, Nb, Sr, P, and Ti are depleted, and variable Eu/Eu* ratios. The whole-rock Sr–Nd isotopic and zircon Hf isotopic compositions show that the Jurassic granitic rocks are mainly recirculation products of Paleo-Mesoproterozoic rocks, as well as the mantle-derived magma, which played a major role in the formation process. Among them, the granites in eastern Guangxi-western Guangdong and Northeast Guangdong areas display higher εNd(t) and εHf(t) values, suggesting a relatively larger contribution from mantle-derived materials. Based on the comprehensive regional geological data, we interpret that these Jurassic granitic rocks as a product of lithosphere extensional-thinning, tectonic-magmatic interaction formed during the process of flat-slab subduction.
{"title":"Petrogenesis of Jurassic granitic rocks in South China Block: Implications for events related to subduction of Paleo-Pacific plate","authors":"Meng-Yu Tian, Yong-Jun Di","doi":"10.1515/geo-2022-0601","DOIUrl":"https://doi.org/10.1515/geo-2022-0601","url":null,"abstract":"Frequent magmatic intrusion and eruption during the early Yanshanian in South China formed a unique and diverse igneous rock assemblage, mainly comprising granite, rhyolite, and some basic rocks. Nevertheless, the tectonic regime responsible for the formation of these granitic rocks remains controversial. The comprehensive available data suggest that the Jurassic granitic rocks formed during the period from 180 to 145 Ma, with an age peak at ca. 160 Ma. Jurassic rocks are predominantly concentrated in Wuyi, southern Hunan, northeast Guangdong, and southern Jiangxi, followed by the eastern Guangxi-western Guangdong areas, mainly including I-, S-, and A-type granites, and a few I–S transformation-type granites. These granitic rocks invariably exhibit enrichment in Rb, Th, U, and Pb, while Ba, Nb, Sr, P, and Ti are depleted, and variable Eu/Eu* ratios. The whole-rock Sr–Nd isotopic and zircon Hf isotopic compositions show that the Jurassic granitic rocks are mainly recirculation products of Paleo-Mesoproterozoic rocks, as well as the mantle-derived magma, which played a major role in the formation process. Among them, the granites in eastern Guangxi-western Guangdong and Northeast Guangdong areas display higher <jats:italic>ε</jats:italic> <jats:sub>Nd</jats:sub>(<jats:italic>t</jats:italic>) and <jats:italic>ε</jats:italic> <jats:sub>Hf</jats:sub>(<jats:italic>t</jats:italic>) values, suggesting a relatively larger contribution from mantle-derived materials. Based on the comprehensive regional geological data, we interpret that these Jurassic granitic rocks as a product of lithosphere extensional-thinning, tectonic-magmatic interaction formed during the process of flat-slab subduction.","PeriodicalId":48712,"journal":{"name":"Open Geosciences","volume":"200 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139952856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study investigated the effects of food culture on the economic and ecological development of rural rivers and adolescents’ intentions toward tourism in high-risk leisure environments. The study applied a mixed-methods design. A questionnaire was designed and distributed to recruited participants, and 900 responses were collected and analyzed, with SPSS 26.0 used to perform basic statistical validation and Pearson’s correlation analysis. Structured interviews were conducted to collect the opinions of experts, tourists, and residents of the investigated areas. A multivariate analysis was used to analyze the results, which revealed that superior economic, societal, and ecological development is associated with greater leisure, tourism, and consumption intentions. However, varying levels of environmental literacy among tourists can present challenges. Problems such as tourism waste; overdevelopment; loss of historic architectural features; and pollution of water, forests, and air may deter young tourists from revisiting an area and diminish their willingness to engage in and share leisure experiences.
{"title":"Adolescents’ consumption intentions toward leisure tourism in high-risk leisure environments in riverine areas","authors":"Hsiao-Hsien Lin, Tzu-Yun Lin, Chih-Cheng Lo, Chao-Yen Lin, Su-Fang Zhang, Po-Hsuan Wu, Qi-Yuan Li, I-En Tsai, Xue-Qi Yan, Jing-Hui Huang, Gan-Hong Chen","doi":"10.1515/geo-2022-0582","DOIUrl":"https://doi.org/10.1515/geo-2022-0582","url":null,"abstract":"This study investigated the effects of food culture on the economic and ecological development of rural rivers and adolescents’ intentions toward tourism in high-risk leisure environments. The study applied a mixed-methods design. A questionnaire was designed and distributed to recruited participants, and 900 responses were collected and analyzed, with SPSS 26.0 used to perform basic statistical validation and Pearson’s correlation analysis. Structured interviews were conducted to collect the opinions of experts, tourists, and residents of the investigated areas. A multivariate analysis was used to analyze the results, which revealed that superior economic, societal, and ecological development is associated with greater leisure, tourism, and consumption intentions. However, varying levels of environmental literacy among tourists can present challenges. Problems such as tourism waste; overdevelopment; loss of historic architectural features; and pollution of water, forests, and air may deter young tourists from revisiting an area and diminish their willingness to engage in and share leisure experiences.","PeriodicalId":48712,"journal":{"name":"Open Geosciences","volume":"38 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139952607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jingran Zhang, Dajiang Geng, Xiaoxia Zhao, Zhicheng Bai, Mingjian Long
Based on the theoretical model of a soil plug column, the stress analysis of the soil plug column during the spinning process of steel casing is carried out, and the critical depth of the soil column is determined using the stress and torsional shear ratio of the soil column. The effect of factors such as casing wall thickness, surface load, and steel casing spinning speed on the critical depth of soil columns has been explored, and more reasonable construction process parameters have been obtained quantitatively. Combined with the construction of small net distance test piles at a distance of 2.5 m from the tunnel, the impact of the construction process on the existing shield tunnel has been explored. The results indicate that during the construction process, when the wall thickness of the steel casing does not exceed 0.012 m, the surface load does not exceed 15 kPa, the spinning speed of the steel casing is maintained at 5/4/2/4 m/h or 5/3/2/3 m/h (corresponding to soil depths of 2.5/9.5/6/14 m), and the soil height of the soil column is controlled within 11 m, it is not easy to generate soil plug inside the steel casing, and the soil column has strong torsional shear resistance. According to the measured data of adjacent tunnels, it has been found that the construction method of fully rotating steel casing bored pile can effectively reduce the impact on adjacent shield tunnels, and has a good microdisturbance effect, which can control tunnel deformation not exceeding 1 mm and maintain within the warning value range.
{"title":"Impact of fully rotating steel casing bored pile on adjacent tunnels","authors":"Jingran Zhang, Dajiang Geng, Xiaoxia Zhao, Zhicheng Bai, Mingjian Long","doi":"10.1515/geo-2022-0600","DOIUrl":"https://doi.org/10.1515/geo-2022-0600","url":null,"abstract":"Based on the theoretical model of a soil plug column, the stress analysis of the soil plug column during the spinning process of steel casing is carried out, and the critical depth of the soil column is determined using the stress and torsional shear ratio of the soil column. The effect of factors such as casing wall thickness, surface load, and steel casing spinning speed on the critical depth of soil columns has been explored, and more reasonable construction process parameters have been obtained quantitatively. Combined with the construction of small net distance test piles at a distance of 2.5 m from the tunnel, the impact of the construction process on the existing shield tunnel has been explored. The results indicate that during the construction process, when the wall thickness of the steel casing does not exceed 0.012 m, the surface load does not exceed 15 kPa, the spinning speed of the steel casing is maintained at 5/4/2/4 m/h or 5/3/2/3 m/h (corresponding to soil depths of 2.5/9.5/6/14 m), and the soil height of the soil column is controlled within 11 m, it is not easy to generate soil plug inside the steel casing, and the soil column has strong torsional shear resistance. According to the measured data of adjacent tunnels, it has been found that the construction method of fully rotating steel casing bored pile can effectively reduce the impact on adjacent shield tunnels, and has a good microdisturbance effect, which can control tunnel deformation not exceeding 1 mm and maintain within the warning value range.","PeriodicalId":48712,"journal":{"name":"Open Geosciences","volume":"18 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139760215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohammed H. Aljahdali, Baradin Adisu, Esubalew Adem, Anis Chaabani, Silvena Boteva, Lifu Zhang, Mohamed Elhag
Normalized difference vegetation index (NDVI) is one of the parameters of vegetation that can be studied by remote sensing of land surface with Sentinel-2 (S-2) satellite image. The NDVI is a nondimensional index that depicts the difference in plant cover reflectivity between visible and near-infrared light and can be used to measure the density of green on a piece of land. On the other hand, the dual-pol radar vegetation index (DpRVI) is one of the indices studied using multispectral synthetic aperture radar (SAR) images. Researchers have identified that SAR images are highly sensitive to identify the buildup of biomass from leaf vegetative growth to the flowering stage. Vegetation biophysical characteristics such as the leaf area index (LAI), vegetation water content, and biomass are frequently used as essential system parameters in remote sensing data assimilation for agricultural production models. In the current study, we have used LAI as a system parameter. The findings of the study revealed that the optical data (NDVI) showed a high correlation (up to 0.712) with LAI and a low root-mean-square error (0.0296) compared to microwave data with 0.4523 root-mean-square error. The NDVI, LAI, and DpRVI mean values all decreased between 2019 and 2020. While the DpRVI continued to decline between 2020 and 2021, the NDVI and LAI saw an increase over the same period, which was likely caused by an increase in the study area’s average annual rainfall and the cautious stance of the Red Global (RSG) project on sustainability.
归一化差异植被指数（NDVI）是利用哨兵-2（S-2）卫星图像对地表进行遥感研究的植被参数之一。归一化差异植被指数是一个非维度指数，描述了植物覆盖在可见光和近红外光之间的反射率差异，可用于测量土地上的绿色密度。另一方面，双波长雷达植被指数（DpRVI）是利用多光谱合成孔径雷达（SAR）图像研究的指数之一。研究人员发现，合成孔径雷达图像对识别从叶片植被生长到开花阶段的生物量积累非常敏感。叶面积指数（LAI）、植被含水量和生物量等植被生物物理特征经常被用作农业生产模型遥感数据同化的基本系统参数。在本研究中，我们将 LAI 作为系统参数。研究结果表明，光学数据（NDVI）与 LAI 的相关性较高（高达 0.712），均方根误差较低（0.0296），而微波数据的均方根误差为 0.4523。2019 年至 2020 年，NDVI、LAI 和 DpRVI 平均值均有所下降。虽然 DpRVI 在 2020 年至 2021 年期间持续下降，但 NDVI 和 LAI 在同一时期却有所上升，这可能是由于研究区域的年均降雨量增加以及 Red Global（RSG）项目对可持续发展的谨慎态度所致。
{"title":"Monitoring of mangrove forests vegetation based on optical versus microwave data: A case study western coast of Saudi Arabia","authors":"Mohammed H. Aljahdali, Baradin Adisu, Esubalew Adem, Anis Chaabani, Silvena Boteva, Lifu Zhang, Mohamed Elhag","doi":"10.1515/geo-2022-0573","DOIUrl":"https://doi.org/10.1515/geo-2022-0573","url":null,"abstract":"Normalized difference vegetation index (NDVI) is one of the parameters of vegetation that can be studied by remote sensing of land surface with Sentinel-2 (S-2) satellite image. The NDVI is a nondimensional index that depicts the difference in plant cover reflectivity between visible and near-infrared light and can be used to measure the density of green on a piece of land. On the other hand, the dual-pol radar vegetation index (DpRVI) is one of the indices studied using multispectral synthetic aperture radar (SAR) images. Researchers have identified that SAR images are highly sensitive to identify the buildup of biomass from leaf vegetative growth to the flowering stage. Vegetation biophysical characteristics such as the leaf area index (LAI), vegetation water content, and biomass are frequently used as essential system parameters in remote sensing data assimilation for agricultural production models. In the current study, we have used LAI as a system parameter. The findings of the study revealed that the optical data (NDVI) showed a high correlation (up to 0.712) with LAI and a low root-mean-square error (0.0296) compared to microwave data with 0.4523 root-mean-square error. The NDVI, LAI, and DpRVI mean values all decreased between 2019 and 2020. While the DpRVI continued to decline between 2020 and 2021, the NDVI and LAI saw an increase over the same period, which was likely caused by an increase in the study area’s average annual rainfall and the cautious stance of the Red Global (RSG) project on sustainability.","PeriodicalId":48712,"journal":{"name":"Open Geosciences","volume":"2 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139760309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yana Chen, Jia Liu, Nan Wang, Yiqing Zhu, Wei Lin, Quansheng Cai, Yuchuan Chen, Mingtao Li
It is a great challenge for sedimentologists to perform the facies analysis of shales due to the lack of macro-structures and high heterogeneity in shale, and thus, conventional research methods are poorly applied in the field of shale sedimentology. To establish a typical depositional model for marine shales, a new method adopted from marine carbonate rocks was employed to perform the microfacies analysis of marine shales of the Wufeng and Longmaxi Formation in Sichuan Basin. This method emphasizes the fact that many skeletal constituents in marine shales have specific bathymetric distributions, allowing for a better understanding of the depositional process of shales. With this approach, a total of nine microfacies were identified and two depositional models for marine shales were proposed. The depositional models show that sea levels were high during the Middle to Late Wufeng period, which was followed by a rapid regression that led to a significant sea-level drop by over 50 m at the topmost of the Wufeng Formation, and consequently, widespread fine-grained sandy shales with large amounts of benthic bioclasts were deposited in the study region. The eustatic sea-level changes recovered by using the method of microfacies analysis are in line with the global trend, indicating that the method has promising applications in the field of marine shale sedimentology.
{"title":"Microfacies analysis of marine shale: A case study of the shales of the Wufeng–Longmaxi formation in the western Chongqing, Sichuan Basin, China","authors":"Yana Chen, Jia Liu, Nan Wang, Yiqing Zhu, Wei Lin, Quansheng Cai, Yuchuan Chen, Mingtao Li","doi":"10.1515/geo-2022-0583","DOIUrl":"https://doi.org/10.1515/geo-2022-0583","url":null,"abstract":"It is a great challenge for sedimentologists to perform the facies analysis of shales due to the lack of macro-structures and high heterogeneity in shale, and thus, conventional research methods are poorly applied in the field of shale sedimentology. To establish a typical depositional model for marine shales, a new method adopted from marine carbonate rocks was employed to perform the microfacies analysis of marine shales of the Wufeng and Longmaxi Formation in Sichuan Basin. This method emphasizes the fact that many skeletal constituents in marine shales have specific bathymetric distributions, allowing for a better understanding of the depositional process of shales. With this approach, a total of nine microfacies were identified and two depositional models for marine shales were proposed. The depositional models show that sea levels were high during the Middle to Late Wufeng period, which was followed by a rapid regression that led to a significant sea-level drop by over 50 m at the topmost of the Wufeng Formation, and consequently, widespread fine-grained sandy shales with large amounts of benthic bioclasts were deposited in the study region. The eustatic sea-level changes recovered by using the method of microfacies analysis are in line with the global trend, indicating that the method has promising applications in the field of marine shale sedimentology.","PeriodicalId":48712,"journal":{"name":"Open Geosciences","volume":"139 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139760307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
One of the major challenges facing geochemistry, petrology, and volcanology researchers is the difficulty in determining the origin and paleo-flow directions of igneous and volcanic rocks. It is not possible to clearly determine origins and paleo-flow directions in areas with numerous volcanic centers. Anisotropy of magnetic susceptibility (AMS) is a valuable method that provides insights into the origins and paleo-flow directions of lavas that are complex to study. The presence of volcanic materials with thicknesses up to 1 km, coming from different sources at varied time intervals in the north of Lake Van, makes this area an ideal setting for implementing AMS in establishing paleo-flow directions. This study presents the magnetic mineralogy and AMS analysis of volcanic rocks from the Miocene to the Quaternary in the Lake Van region. We conducted isothermal remanent magnetization (IRM) and high-temperature susceptibility (HTS) studies to determine the magnetic mineralogy. IRM studies revealed that (titano)magnetite is responsible for the magnetization in most samples, while both (titano)magnetite and hematite are responsible for the rest. Alteration degrees and Curie temperatures of the rock samples were also determined through HTS measurements. There is good agreement between the anticipated directions of lava flow and our findings for nearly all volcanic rocks.
{"title":"Identification of magnetic mineralogy and paleo-flow direction of the Miocene-quaternary volcanic products in the north of Lake Van, Eastern Turkey","authors":"Sercan Kayın, Turgay İşseven","doi":"10.1515/geo-2022-0605","DOIUrl":"https://doi.org/10.1515/geo-2022-0605","url":null,"abstract":"One of the major challenges facing geochemistry, petrology, and volcanology researchers is the difficulty in determining the origin and paleo-flow directions of igneous and volcanic rocks. It is not possible to clearly determine origins and paleo-flow directions in areas with numerous volcanic centers. Anisotropy of magnetic susceptibility (AMS) is a valuable method that provides insights into the origins and paleo-flow directions of lavas that are complex to study. The presence of volcanic materials with thicknesses up to 1 km, coming from different sources at varied time intervals in the north of Lake Van, makes this area an ideal setting for implementing AMS in establishing paleo-flow directions. This study presents the magnetic mineralogy and AMS analysis of volcanic rocks from the Miocene to the Quaternary in the Lake Van region. We conducted isothermal remanent magnetization (IRM) and high-temperature susceptibility (HTS) studies to determine the magnetic mineralogy. IRM studies revealed that (titano)magnetite is responsible for the magnetization in most samples, while both (titano)magnetite and hematite are responsible for the rest. Alteration degrees and Curie temperatures of the rock samples were also determined through HTS measurements. There is good agreement between the anticipated directions of lava flow and our findings for nearly all volcanic rocks.","PeriodicalId":48712,"journal":{"name":"Open Geosciences","volume":"30 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139772720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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