17 Abstract—This study outlines a method for generating an 18 automated micro-landform map of an ... more 17 Abstract—This study outlines a method for generating an 18 automated micro-landform map of an alluvial plain for 19 further flood hazard assessment by combining Shuttle Radar 20 Topographic Mission Digital Elevation Model (SRTM DEM) 21 and satellite images. Average elevation and channel features 22 extracted from DEM are associated with soil moist condition 23 (thresholds of Modified Normalized Difference Water Index 24 – MNDWI) from remotely sensed images based on a logic 25 rule. This process is conducted in GRASS GIS. SRTM DEM 26 is known as consistent and useful data for landform mapping 27 by digital terrain analyses. However, because of its limitation 28 in spatial resolution, satellite images are combined to isolate 29 micro-landforms in alluvial plains (flat and low relief). 30 Another merit of this automated method in comparison of a 31 manual method is time-saving, objective and simple for 32 editing. Although, theoretically, manual mapping by aerial 33 photos and topog...
The objective of this research is to study the role of a tsunami, generated by the 1498 Meio eart... more The objective of this research is to study the role of a tsunami, generated by the 1498 Meio earthquake (M8.2 - 8.4) along the eastern Nankai on the geomorphological evolution of the Hamana river floodplain, located along the Pacific coastline of Central Japan (Shizuoka prefecture). Historical sources document a sudden decline at the end of the 15th century of the harbour town Hashimoto, located along the river Hamana. Before the 15th century, this river connected the Pacific Ocean with an enclosed coastal embayment separated by a sand barrier (i.e. the present-day Hamana lake) from the Pacific. The reconstruction of the palaeocourse of the Hamana river was carried out on the basis of detailed facies and diatom analyses of undisturbed sediment cores (geoslicer and drilling). The palaeochannel was detected along the western side of the present-day coastal embayment. It seems that the river's mouth was abruptly sealed off due to the migration of huge volumes of sand that initiated...
ABSTRACT Flood susceptibility mapping using geomorphologic approaches is effective for delineatin... more ABSTRACT Flood susceptibility mapping using geomorphologic approaches is effective for delineating flood extent and various degrees of potential flood-affected areas. This approach is useful where the channel system and floodplain morphology change dynamically and in regions where detailed digital elevation models are not available. The first important step in flood zonation using this approach is detailed geomorphologic mapping, also called landform classification. This study aims to describe landform classification using the rule-based method of Ho et al. (Int J Geoinform 8(4):27–38, 2012) adapted to local characteristics in the western plain of the Red River delta, northern Vietnam. The original classification scheme is generally based on the moist condition classification, local land-surface parameters, and relative position indices derived from multi-temporal Landsat data and a shuttle radar topographic mission digital elevation model (SRTM DEM). This study uses average elevations and the standard deviation of elevations as local land-surface parameters rather than local relief, which was used in the study by Ho et al. (Int J Geoinform 8(4):27–38, 2012). Multi-temporal land cover classification was performed using an integrated method to effectively correct the SRTM DEM. The overall classification is consistent with manual mapping by visual comparison. The quantitative comparison between landform units and past flood-affected areas demonstrates a precise boundary delineation of landform objects using this method. The high agreement between the boundaries of landform units and flood-inundated areas suggests the applicability of this method taking advantage of readily available remotely sensed datasets in alluvial floodplains.
Abstract: The Shoalhaven River is one of the largest rivers on the south coast of New South Wales... more Abstract: The Shoalhaven River is one of the largest rivers on the south coast of New South Wales, and the deltaic-estuarine plains associated with its mouth represent a mature stage of infill of a barrier estuary. The stratigraphy of sediments from more than 60 drillholes from the plains indicates that the area has infilled during the mid-Holocene as a result of input of marine sands associated with a sand barrier on the high-energy coast, and fluvial mud and sands from the Shoalhaven River. Molluscan assemblages indicate that marine influence was initially widespread throughout the eastern and southern parts of the embayment, and that most of the plains infilled under estuarine conditions. Prominent levees across the plains surface are interpreted to be part of a birdsfoot delta distributary complex, and individual floodbasins accreted progressively as they were encapsulated by distributary extension. These former tidal environments mean that there are extensive potential acid sul...
Journal of The Sedimentological Society of Japan, 1992
The Kiso river delta locates in the southern part of the Nobi plain, central Japan. Evolution of ... more The Kiso river delta locates in the southern part of the Nobi plain, central Japan. Evolution of the delta has been strongly influenced by post-glacial sea-level changes, and landforms of the delta changed remarkably during the Holocene. Holocene sediments of the delta can be classified into the lower sandy, middle muddy, upper sandy and -uppermost terrestrial units. Silty or sandy transitional zones can be recognized in the upper and lower horizones of the middle muddy units by means of a particle size analysis. Sediments of the transitional zones are considered to be deposited between the foreset and bottom set beds of the delta as delta front sediments. Based on the 14C ages and characteristics of the sedimentary facies, Holocene sequence and evolution of the Kiso river delta are considered as follows. The post glacial transgression in the early Holocene (10000-8500 years BP) was slow, and in this slow transgressive stage, the lower sandy unit deposited as the flood plain sedimen...
17 Abstract—This study outlines a method for generating an 18 automated micro-landform map of an ... more 17 Abstract—This study outlines a method for generating an 18 automated micro-landform map of an alluvial plain for 19 further flood hazard assessment by combining Shuttle Radar 20 Topographic Mission Digital Elevation Model (SRTM DEM) 21 and satellite images. Average elevation and channel features 22 extracted from DEM are associated with soil moist condition 23 (thresholds of Modified Normalized Difference Water Index 24 – MNDWI) from remotely sensed images based on a logic 25 rule. This process is conducted in GRASS GIS. SRTM DEM 26 is known as consistent and useful data for landform mapping 27 by digital terrain analyses. However, because of its limitation 28 in spatial resolution, satellite images are combined to isolate 29 micro-landforms in alluvial plains (flat and low relief). 30 Another merit of this automated method in comparison of a 31 manual method is time-saving, objective and simple for 32 editing. Although, theoretically, manual mapping by aerial 33 photos and topog...
The objective of this research is to study the role of a tsunami, generated by the 1498 Meio eart... more The objective of this research is to study the role of a tsunami, generated by the 1498 Meio earthquake (M8.2 - 8.4) along the eastern Nankai on the geomorphological evolution of the Hamana river floodplain, located along the Pacific coastline of Central Japan (Shizuoka prefecture). Historical sources document a sudden decline at the end of the 15th century of the harbour town Hashimoto, located along the river Hamana. Before the 15th century, this river connected the Pacific Ocean with an enclosed coastal embayment separated by a sand barrier (i.e. the present-day Hamana lake) from the Pacific. The reconstruction of the palaeocourse of the Hamana river was carried out on the basis of detailed facies and diatom analyses of undisturbed sediment cores (geoslicer and drilling). The palaeochannel was detected along the western side of the present-day coastal embayment. It seems that the river's mouth was abruptly sealed off due to the migration of huge volumes of sand that initiated...
ABSTRACT Flood susceptibility mapping using geomorphologic approaches is effective for delineatin... more ABSTRACT Flood susceptibility mapping using geomorphologic approaches is effective for delineating flood extent and various degrees of potential flood-affected areas. This approach is useful where the channel system and floodplain morphology change dynamically and in regions where detailed digital elevation models are not available. The first important step in flood zonation using this approach is detailed geomorphologic mapping, also called landform classification. This study aims to describe landform classification using the rule-based method of Ho et al. (Int J Geoinform 8(4):27–38, 2012) adapted to local characteristics in the western plain of the Red River delta, northern Vietnam. The original classification scheme is generally based on the moist condition classification, local land-surface parameters, and relative position indices derived from multi-temporal Landsat data and a shuttle radar topographic mission digital elevation model (SRTM DEM). This study uses average elevations and the standard deviation of elevations as local land-surface parameters rather than local relief, which was used in the study by Ho et al. (Int J Geoinform 8(4):27–38, 2012). Multi-temporal land cover classification was performed using an integrated method to effectively correct the SRTM DEM. The overall classification is consistent with manual mapping by visual comparison. The quantitative comparison between landform units and past flood-affected areas demonstrates a precise boundary delineation of landform objects using this method. The high agreement between the boundaries of landform units and flood-inundated areas suggests the applicability of this method taking advantage of readily available remotely sensed datasets in alluvial floodplains.
Abstract: The Shoalhaven River is one of the largest rivers on the south coast of New South Wales... more Abstract: The Shoalhaven River is one of the largest rivers on the south coast of New South Wales, and the deltaic-estuarine plains associated with its mouth represent a mature stage of infill of a barrier estuary. The stratigraphy of sediments from more than 60 drillholes from the plains indicates that the area has infilled during the mid-Holocene as a result of input of marine sands associated with a sand barrier on the high-energy coast, and fluvial mud and sands from the Shoalhaven River. Molluscan assemblages indicate that marine influence was initially widespread throughout the eastern and southern parts of the embayment, and that most of the plains infilled under estuarine conditions. Prominent levees across the plains surface are interpreted to be part of a birdsfoot delta distributary complex, and individual floodbasins accreted progressively as they were encapsulated by distributary extension. These former tidal environments mean that there are extensive potential acid sul...
Journal of The Sedimentological Society of Japan, 1992
The Kiso river delta locates in the southern part of the Nobi plain, central Japan. Evolution of ... more The Kiso river delta locates in the southern part of the Nobi plain, central Japan. Evolution of the delta has been strongly influenced by post-glacial sea-level changes, and landforms of the delta changed remarkably during the Holocene. Holocene sediments of the delta can be classified into the lower sandy, middle muddy, upper sandy and -uppermost terrestrial units. Silty or sandy transitional zones can be recognized in the upper and lower horizones of the middle muddy units by means of a particle size analysis. Sediments of the transitional zones are considered to be deposited between the foreset and bottom set beds of the delta as delta front sediments. Based on the 14C ages and characteristics of the sedimentary facies, Holocene sequence and evolution of the Kiso river delta are considered as follows. The post glacial transgression in the early Holocene (10000-8500 years BP) was slow, and in this slow transgressive stage, the lower sandy unit deposited as the flood plain sedimen...
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