Alan Kasprak (Former Employee)
Science and Products
Filter Total Items: 19
The effects of topographic surveying technique and data resolution on the detection and interpretation of geomorphic change
Change detection of high resolution topographic data is commonly used in river valleys to quantify reach- and site-scale sediment budgets by estimating the erosion/deposition volume, and to interpret the geomorphic processes driving erosion and deposition. Field survey data are typically collected as point clouds that are often converted to gridded raster datasets and the ultimate choice of grid r
Authors
Alan Kasprak, Nathaniel D. Bransky, Joel B. Sankey, Joshua Caster, Temulen T. Sankey
Quantifying and forecasting changes in the areal extent of river valley sediment in response to altered hydrology and land cover
In river valleys, sediment moves between active river channels, near-channel deposits including bars and floodplains, and upland environments such as terraces and aeolian dunefields. Sediment availability is a prerequisite for the sustained transfer of material between these areas, and for the eco-geomorphic functioning of river networks in general. However, the difficulty of monitoring sediment a
Authors
Alan Kasprak, Joel B. Sankey, Daniel Buscombe, Joshua Caster, Amy E. East, Paul E. Grams
The response of source-bordering aeolian dunefields to sediment-supply changes 1: Effects of wind variability and river-valley morphodynamics
Source-bordering dunefields (SBDs), which are primarily built and maintained with river-derived sediment, are found in many large river valleys and are currently impacted by changes in sediment supply due to climate change, land use changes, and river regulation. Despite their importance, a physically based, applied approach for quantifying the response of SBDs to changes in sediment supply does n
Authors
Joel B. Sankey, Alan Kasprak, Joshua Caster, Amy E. East, Helen C. Fairley
The response of source-bordering aeolian dunefields to sediment-supply changes 2: Controlled floods of the Colorado River in Grand Canyon, Arizona, USA
In the Colorado River downstream of Glen Canyon Dam in the Grand Canyon, USA, controlled floods are used to resupply sediment to, and rebuild, river sandbars that have eroded severely over the past five decades owing to dam-induced changes in river flow and sediment supply. In this study, we examine whether controlled floods, can in turn resupply aeolian sediment to some of the large source-border
Authors
Joel B. Sankey, Joshua Caster, Alan Kasprak, Amy E. East
Modern landscape processes affecting archaeological sites along the Colorado River corridor downstream of Glen Canyon Dam, Glen Canyon National Recreation Area, Arizona
The landscape of the Colorado River through Glen Canyon National Recreation Area formed over many thousands of years and was modified substantially after the completion of Glen Canyon Dam in 1963. Changes to river flow, sediment supply, channel base level, lateral extent of sedimentary terraces, and vegetation in the post-dam era have modified the river-corridor landscape and have altered the effe
Authors
Amy E. East, Joel B. Sankey, Helen C. Fairley, Joshua J. Caster, Alan Kasprak
Geomorphic process from topographic form: automating the interpretation of repeat survey data in river valleys
The ability to quantify the processes driving geomorphic change in river valley margins is vital to geomorphologists seeking to understand the relative role of transport mechanisms (e.g. fluvial, aeolian, and hillslope processes) in landscape dynamics. High-resolution, repeat topographic data are becoming readily available to geomorphologists. By contrasting digital elevation models derived from r
Authors
Alan Kasprak, Joshua J. Caster, Sara G. Bangen, Joel B. Sankey
Linking fluvial and aeolian morphodynamics in the Grand Canyon, USA
In river valleys, fluvial and upland landscapes are intrinsically linked through sediment exchange between the active channel, near-channel fluvial deposits, and higher elevation upland deposits. During floods, sediment is transferred from channels to low-elevation nearchannel deposits [Schmidt and Rubin, 1995]. Particularly in dryland river valleys, subsequent aeolian reworking of these flood dep
Authors
Alan Kasprak, Sara G. Bangen, Daniel Buscombe, Joshua Caster, Amy E. East, Paul E. Grams, Joel B. Sankey
Science and Products
Filter Total Items: 19
The effects of topographic surveying technique and data resolution on the detection and interpretation of geomorphic change
Change detection of high resolution topographic data is commonly used in river valleys to quantify reach- and site-scale sediment budgets by estimating the erosion/deposition volume, and to interpret the geomorphic processes driving erosion and deposition. Field survey data are typically collected as point clouds that are often converted to gridded raster datasets and the ultimate choice of grid r
Authors
Alan Kasprak, Nathaniel D. Bransky, Joel B. Sankey, Joshua Caster, Temulen T. Sankey
Quantifying and forecasting changes in the areal extent of river valley sediment in response to altered hydrology and land cover
In river valleys, sediment moves between active river channels, near-channel deposits including bars and floodplains, and upland environments such as terraces and aeolian dunefields. Sediment availability is a prerequisite for the sustained transfer of material between these areas, and for the eco-geomorphic functioning of river networks in general. However, the difficulty of monitoring sediment a
Authors
Alan Kasprak, Joel B. Sankey, Daniel Buscombe, Joshua Caster, Amy E. East, Paul E. Grams
The response of source-bordering aeolian dunefields to sediment-supply changes 1: Effects of wind variability and river-valley morphodynamics
Source-bordering dunefields (SBDs), which are primarily built and maintained with river-derived sediment, are found in many large river valleys and are currently impacted by changes in sediment supply due to climate change, land use changes, and river regulation. Despite their importance, a physically based, applied approach for quantifying the response of SBDs to changes in sediment supply does n
Authors
Joel B. Sankey, Alan Kasprak, Joshua Caster, Amy E. East, Helen C. Fairley
The response of source-bordering aeolian dunefields to sediment-supply changes 2: Controlled floods of the Colorado River in Grand Canyon, Arizona, USA
In the Colorado River downstream of Glen Canyon Dam in the Grand Canyon, USA, controlled floods are used to resupply sediment to, and rebuild, river sandbars that have eroded severely over the past five decades owing to dam-induced changes in river flow and sediment supply. In this study, we examine whether controlled floods, can in turn resupply aeolian sediment to some of the large source-border
Authors
Joel B. Sankey, Joshua Caster, Alan Kasprak, Amy E. East
Modern landscape processes affecting archaeological sites along the Colorado River corridor downstream of Glen Canyon Dam, Glen Canyon National Recreation Area, Arizona
The landscape of the Colorado River through Glen Canyon National Recreation Area formed over many thousands of years and was modified substantially after the completion of Glen Canyon Dam in 1963. Changes to river flow, sediment supply, channel base level, lateral extent of sedimentary terraces, and vegetation in the post-dam era have modified the river-corridor landscape and have altered the effe
Authors
Amy E. East, Joel B. Sankey, Helen C. Fairley, Joshua J. Caster, Alan Kasprak
Geomorphic process from topographic form: automating the interpretation of repeat survey data in river valleys
The ability to quantify the processes driving geomorphic change in river valley margins is vital to geomorphologists seeking to understand the relative role of transport mechanisms (e.g. fluvial, aeolian, and hillslope processes) in landscape dynamics. High-resolution, repeat topographic data are becoming readily available to geomorphologists. By contrasting digital elevation models derived from r
Authors
Alan Kasprak, Joshua J. Caster, Sara G. Bangen, Joel B. Sankey
Linking fluvial and aeolian morphodynamics in the Grand Canyon, USA
In river valleys, fluvial and upland landscapes are intrinsically linked through sediment exchange between the active channel, near-channel fluvial deposits, and higher elevation upland deposits. During floods, sediment is transferred from channels to low-elevation nearchannel deposits [Schmidt and Rubin, 1995]. Particularly in dryland river valleys, subsequent aeolian reworking of these flood dep
Authors
Alan Kasprak, Sara G. Bangen, Daniel Buscombe, Joshua Caster, Amy E. East, Paul E. Grams, Joel B. Sankey