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Mark Reid

Mark Reid is a research hydrologist for California Volcano Observatory.

Science and Products

Grfin Tools download icon

Grfin Tools – Methods and software for modeling landslide runout and debris-flow growth and inundation

Grfin Tools is a set of software tools that allows users to quickly estimate potential runout from landslides, and (or) inundation from debris flows or lahars, within a DEM. Grfin (pronounced "griffin") is an acronym of  Growth +  flow +  inundation, and the tools within this package apply simple, well-tested, empirical models of runout. This suite of tools can be used individually or in...
By
Natural Hazards Mission Area, Landslide Hazards Program
Grfin Tools – Methods and software for modeling landslide runout and debris-flow growth and inundation

Grfin Tools – Methods and software for modeling landslide runout and debris-flow growth and inundation

Grfin Tools is a set of software tools that allows users to quickly estimate potential runout from landslides, and (or) inundation from debris flows or lahars, within a DEM. Grfin (pronounced "griffin") is an acronym of  Growth +  flow +  inundation, and the tools within this package apply simple, well-tested, empirical models of runout. This suite of tools can be used individually or in...
Learn More
Aerial view of the Mill Creek landslide blocking Highway 50.

U.S. Highway 50, California - Monitoring Discontinued

As of October 2024, U.S. Geological Survey (USGS) monitoring at this landslide has been discontinued. In previous years since 1997, the landslide was monitored using data acquisition systems and radio telemetry developed by the USGS Volcano Hazards Program to operate in remote, hazardous sites with limited power. At this landslide, infiltration of rainfall or rapid snowmelt increases groundwater...
By
Natural Hazards Mission Area, Landslide Hazards Program, Geologic Hazards Science Center
U.S. Highway 50, California - Monitoring Discontinued

U.S. Highway 50, California - Monitoring Discontinued

As of October 2024, U.S. Geological Survey (USGS) monitoring at this landslide has been discontinued. In previous years since 1997, the landslide was monitored using data acquisition systems and radio telemetry developed by the USGS Volcano Hazards Program to operate in remote, hazardous sites with limited power. At this landslide, infiltration of rainfall or rapid snowmelt increases groundwater...
Learn More

10-Minute GPS Monitoring Data for the Cleveland Corral landslide near U.S. Highway 50, El Dorado County, California 10-Minute GPS Monitoring Data for the Cleveland Corral landslide near U.S. Highway 50, El Dorado County, California

This data release documents movement of the toe of Cleveland Corral Landslide, El Dorado County, CA from October 1, 2016, to September 30, 2017, based on GPS data from near real-time monitoring. Raw GPS data from L1-only receivers were recorded in 15 second epochs using data acquisition systems and radio telemetry developed by the USGS Volcano Hazards Program. The overall system, named...
By
Volcano Science Center

Location, length, and height of landslides triggered by tropical storm Chata'an in Chuuk, Federated States of Micronesia Location, length, and height of landslides triggered by tropical storm Chata'an in Chuuk, Federated States of Micronesia

In 2002, tropical storm Chata’an triggered more than 250 landslides in Chuuk, Federated States of Micronesia (Harp and others, 2004). This data release includes shapefiles of the original mapping from oblique aerial photographs of landslide-affected areas (source and runout) (Harp and others, 2004), extraction of height (H) and length (L) from the original mapped landslides, and revised...
By
Volcano Science Center

Field Observations of Past Debris Flows, February 2024, Pohnpei State, Federated States of Micronesia Field Observations of Past Debris Flows, February 2024, Pohnpei State, Federated States of Micronesia

Landslide hazards pose a significant threat to communities and infrastructure across the Federated States of Micronesia (FSM). To support hazard assessment and mitigation efforts, the USGS Landslide Disaster Assistance Team (LDAT) produced landslide susceptibility and debris-flow runout models and map products for Pohnpei State, FSM. For more information on the LDAT FSM project, refer to...
By
Geology, Minerals, Energy, and Geophysics Science Center

Field Observations of Past Debris Flows, February 2024, Kosrae State, Federated States of Micronesia Field Observations of Past Debris Flows, February 2024, Kosrae State, Federated States of Micronesia

Landslide hazards pose a significant threat to communities and infrastructure across the Federated States of Micronesia (FSM). To support hazard assessment and mitigation efforts, the USGS Landslide Disaster Assistance Team (LDAT) produced landslide susceptibility and debris-flow runout models and map products for Kosrae State, FSM. For more information on the LDAT FSM project, refer to...
By
Geology, Minerals, Energy, and Geophysics Science Center

Field Observations of Past Debris Flows, February 2024, Chuuk State, Federated States of Micronesia Field Observations of Past Debris Flows, February 2024, Chuuk State, Federated States of Micronesia

Landslide hazards pose a significant threat to communities and infrastructure across the Federated States of Micronesia (FSM). To support hazard assessment and mitigation efforts, the USGS Landslide Disaster Assistance Team (LDAT) produced landslide susceptibility and debris-flow runout models and map products for Chuuk State, FSM. For more information on the LDAT FSM project, refer to...
By
Geology, Minerals, Energy, and Geophysics Science Center

Displacement and pore-pressure data from a field-scale landslide initiation experiment at Mount Kaba-san, Japan, November 14, 2003 Displacement and pore-pressure data from a field-scale landslide initiation experiment at Mount Kaba-san, Japan, November 14, 2003

This data release contains displacement and pore-water pressure data from a field experiment performed November 14, 2003, at Mount Kaba-san, Japan. This experiment generated a shallow landslide, induced by water infiltration from overhead sprinkling, that mobilized into a debris flow. More information about this experiment can be found in Ochiai and others (2004). Extensometer data...
By
Volcano Hazards Program
Image: 2005 Landslide in Conchita, CA
2005 Landslide in Conchita, CA
2005 Landslide in Conchita, CA
Image: 2005 Landslide in Conchita, CA

2005 Landslide in Conchita, CA

2005 Landslide in Conchita, CA

This landslide occurred at La Conchita, California in 2005. Ten people were killed.

By
Natural Hazards Mission Area, Landslide Hazards Program, Communications and Publishing
Image: 2005 Landslide in Conchita, CA

2005 Landslide in Conchita, CA

2005 Landslide in Conchita, CA

This landslide occurred at La Conchita, California in 2005. Ten people were killed.

By
Natural Hazards Mission Area, Landslide Hazards Program, Communications and Publishing
Image: Oso, Washington Landslide
Oso, Washington Landslide
Oso, Washington Landslide
Image: Oso, Washington Landslide

Oso, Washington Landslide

Oso, Washington Landslide

Oblique aerial photograph of the Oso, Washington landslide, showing the entire extent of the landslide source area and path.

Location: State Route 530, Oso, Washington

By
Natural Hazards Mission Area, Landslide Hazards Program, Communications and Publishing
Image: Oso, Washington Landslide

Oso, Washington Landslide

Oso, Washington Landslide

Oblique aerial photograph of the Oso, Washington landslide, showing the entire extent of the landslide source area and path.

Location: State Route 530, Oso, Washington

By
Natural Hazards Mission Area, Landslide Hazards Program, Communications and Publishing
Filter Total Items: 41

Shear surface undulations modulate clayey gouge strength and contribute to divergent landslide acceleration Shear surface undulations modulate clayey gouge strength and contribute to divergent landslide acceleration

Landslides display a spectrum of speeds for incompletely known reasons. Sliding occurs along slickensided undulatory shear surfaces within boundary shear gouge. Laboratory tests reveal that gouge shear strength generally decreases with finite cumulative displacement during relatively rapid failure and may increase or decrease with increasing shear rate; these behaviors can result in...
Authors
William H. Schulz, Gonghui Wang, Yao Jiang, Brian D. Collins, Mark E. Reid, Mason Muir Einbund
By
Geologic Hazards Science Center

Topographic controls on landslide mobility: Modeling hurricane-induced landslide runout and debris-flow inundation in Puerto Rico Topographic controls on landslide mobility: Modeling hurricane-induced landslide runout and debris-flow inundation in Puerto Rico

In 2017, Hurricane Maria triggered more than 70 000 landslides in Puerto Rico. After initiation, these predominantly shallow landslides were mobilized to varying extents – some landslides only traveled partway downslope, whereas others reached drainage channels and were mobilized into long-traveled debris flows that could severely impact roads and infrastructure. Thus, forecasting...
Authors
Dianne L. Brien, Mark E. Reid, Collin Cronkite-Ratcliff, Jonathan P. Perkins
By
Volcano Hazards Program, Volcano Science Center

Grfin Tools—User guide and methods for modeling landslide runout and debris-flow growth and inundation Grfin Tools—User guide and methods for modeling landslide runout and debris-flow growth and inundation

The software package, Grfin Tools, can estimate potential runout from landslides or inundation from geophysical mass flows such as debris flows, lahars from volcanoes, and rock avalanches within a digital elevation model (DEM). Grfin is an acronym of growth + flow + inundation. The tools within this package apply simple, well-tested, empirical models of runout that are computationally...
Authors
Mark E. Reid, Dianne L. Brien, Collin Cronkite-Ratcliff, Jonathan P. Perkins
By
Natural Hazards Mission Area, Landslide Hazards Program, Volcano Hazards Program, Volcano Science Center

Assessing locations susceptible to shallow landslide initiation during prolonged intense rainfall in the Lares, Utuado, and Naranjito municipalities of Puerto Rico Assessing locations susceptible to shallow landslide initiation during prolonged intense rainfall in the Lares, Utuado, and Naranjito municipalities of Puerto Rico

Hurricane Maria induced about 70 000 landslides throughout Puerto Rico, USA, including thousands each in three municipalities situated in Puerto Rico's rugged Cordillera Central range. By combining a nonlinear soil-depth model, presumed wettest-case pore pressures, and quasi-three-dimensional (3D) slope-stability analysis, we developed a landslide susceptibility map that has very good...
Authors
Rex L. Baum, Dianne L. Brien, Mark E. Reid, William H. Schulz, Matthew J. Tello
By
Natural Hazards Mission Area, Landslide Hazards Program, Geologic Hazards Science Center

Lateral edifice collapse and volcanic debris avalanches: A post-1980 Mount St. Helens perspective Lateral edifice collapse and volcanic debris avalanches: A post-1980 Mount St. Helens perspective

The 1980 eruption of Mount St. Helens was instrumental in advancing understanding of how volcanoes work. Lateral edifice collapses and the generation of volcanic debris avalanches were not widely recognized prior to that eruption, making assessment of their hazards and risks challenging. The proliferation of studies since 1980 on resulting deposits and evaluation of processes leading to...
Authors
Lee Siebert, Mark E. Reid
By
Volcano Hazards Program, Geology, Minerals, Energy, and Geophysics Science Center, Volcano Science Center

Using integrated growth to delineate debris-flow inundation Using integrated growth to delineate debris-flow inundation

Debris-flow volume is fundamental to mobility, yet many debris flows change volume as they travel. Growth can occur through diverse processes such as channel-bed entrainment, bank failures, aggregation of landslides, and coalescence of multiple flows. Integrating growth, either over upslope area or stream length, combines the effects of these growth processes and requires specification...
Authors
Mark E. Reid, Dianne L. Brien, Collin Cronkite-Ratcliff, Jonathan P. Perkins
By
Volcano Hazards Program, Geology, Minerals, Energy, and Geophysics Science Center, Volcano Science Center

Grfin Tools—Software Package and Runtime Documentation for Users Grfin Tools—Software Package and Runtime Documentation for Users

Grfin Tools (an acronym of Growth + flow + inundation) is a set of software tools for portraying areas potentially impacted by runout from landslides or inundation from geophysical mass-flows (such as debris flows) with or without growth as they travel. Grfin Tools allows users to assess the effects of a wide range of factors that can influence mobility. The software also enables runout
By
Landslide Hazards Program, Geology, Minerals, Energy, and Geophysics Science Center

Science and Products

Grfin Tools download icon

Grfin Tools – Methods and software for modeling landslide runout and debris-flow growth and inundation

Grfin Tools is a set of software tools that allows users to quickly estimate potential runout from landslides, and (or) inundation from debris flows or lahars, within a DEM. Grfin (pronounced "griffin") is an acronym of  Growth +  flow +  inundation, and the tools within this package apply simple, well-tested, empirical models of runout. This suite of tools can be used individually or in...
By
Natural Hazards Mission Area, Landslide Hazards Program
Grfin Tools – Methods and software for modeling landslide runout and debris-flow growth and inundation

Grfin Tools – Methods and software for modeling landslide runout and debris-flow growth and inundation

Grfin Tools is a set of software tools that allows users to quickly estimate potential runout from landslides, and (or) inundation from debris flows or lahars, within a DEM. Grfin (pronounced "griffin") is an acronym of  Growth +  flow +  inundation, and the tools within this package apply simple, well-tested, empirical models of runout. This suite of tools can be used individually or in...
Learn More
Aerial view of the Mill Creek landslide blocking Highway 50.

U.S. Highway 50, California - Monitoring Discontinued

As of October 2024, U.S. Geological Survey (USGS) monitoring at this landslide has been discontinued. In previous years since 1997, the landslide was monitored using data acquisition systems and radio telemetry developed by the USGS Volcano Hazards Program to operate in remote, hazardous sites with limited power. At this landslide, infiltration of rainfall or rapid snowmelt increases groundwater...
By
Natural Hazards Mission Area, Landslide Hazards Program, Geologic Hazards Science Center
U.S. Highway 50, California - Monitoring Discontinued

U.S. Highway 50, California - Monitoring Discontinued

As of October 2024, U.S. Geological Survey (USGS) monitoring at this landslide has been discontinued. In previous years since 1997, the landslide was monitored using data acquisition systems and radio telemetry developed by the USGS Volcano Hazards Program to operate in remote, hazardous sites with limited power. At this landslide, infiltration of rainfall or rapid snowmelt increases groundwater...
Learn More

10-Minute GPS Monitoring Data for the Cleveland Corral landslide near U.S. Highway 50, El Dorado County, California 10-Minute GPS Monitoring Data for the Cleveland Corral landslide near U.S. Highway 50, El Dorado County, California

This data release documents movement of the toe of Cleveland Corral Landslide, El Dorado County, CA from October 1, 2016, to September 30, 2017, based on GPS data from near real-time monitoring. Raw GPS data from L1-only receivers were recorded in 15 second epochs using data acquisition systems and radio telemetry developed by the USGS Volcano Hazards Program. The overall system, named...
By
Volcano Science Center

Location, length, and height of landslides triggered by tropical storm Chata'an in Chuuk, Federated States of Micronesia Location, length, and height of landslides triggered by tropical storm Chata'an in Chuuk, Federated States of Micronesia

In 2002, tropical storm Chata’an triggered more than 250 landslides in Chuuk, Federated States of Micronesia (Harp and others, 2004). This data release includes shapefiles of the original mapping from oblique aerial photographs of landslide-affected areas (source and runout) (Harp and others, 2004), extraction of height (H) and length (L) from the original mapped landslides, and revised...
By
Volcano Science Center

Field Observations of Past Debris Flows, February 2024, Pohnpei State, Federated States of Micronesia Field Observations of Past Debris Flows, February 2024, Pohnpei State, Federated States of Micronesia

Landslide hazards pose a significant threat to communities and infrastructure across the Federated States of Micronesia (FSM). To support hazard assessment and mitigation efforts, the USGS Landslide Disaster Assistance Team (LDAT) produced landslide susceptibility and debris-flow runout models and map products for Pohnpei State, FSM. For more information on the LDAT FSM project, refer to...
By
Geology, Minerals, Energy, and Geophysics Science Center

Field Observations of Past Debris Flows, February 2024, Kosrae State, Federated States of Micronesia Field Observations of Past Debris Flows, February 2024, Kosrae State, Federated States of Micronesia

Landslide hazards pose a significant threat to communities and infrastructure across the Federated States of Micronesia (FSM). To support hazard assessment and mitigation efforts, the USGS Landslide Disaster Assistance Team (LDAT) produced landslide susceptibility and debris-flow runout models and map products for Kosrae State, FSM. For more information on the LDAT FSM project, refer to...
By
Geology, Minerals, Energy, and Geophysics Science Center

Field Observations of Past Debris Flows, February 2024, Chuuk State, Federated States of Micronesia Field Observations of Past Debris Flows, February 2024, Chuuk State, Federated States of Micronesia

Landslide hazards pose a significant threat to communities and infrastructure across the Federated States of Micronesia (FSM). To support hazard assessment and mitigation efforts, the USGS Landslide Disaster Assistance Team (LDAT) produced landslide susceptibility and debris-flow runout models and map products for Chuuk State, FSM. For more information on the LDAT FSM project, refer to...
By
Geology, Minerals, Energy, and Geophysics Science Center

Displacement and pore-pressure data from a field-scale landslide initiation experiment at Mount Kaba-san, Japan, November 14, 2003 Displacement and pore-pressure data from a field-scale landslide initiation experiment at Mount Kaba-san, Japan, November 14, 2003

This data release contains displacement and pore-water pressure data from a field experiment performed November 14, 2003, at Mount Kaba-san, Japan. This experiment generated a shallow landslide, induced by water infiltration from overhead sprinkling, that mobilized into a debris flow. More information about this experiment can be found in Ochiai and others (2004). Extensometer data...
By
Volcano Hazards Program
Image: 2005 Landslide in Conchita, CA
2005 Landslide in Conchita, CA
2005 Landslide in Conchita, CA
Image: 2005 Landslide in Conchita, CA

2005 Landslide in Conchita, CA

2005 Landslide in Conchita, CA

This landslide occurred at La Conchita, California in 2005. Ten people were killed.

By
Natural Hazards Mission Area, Landslide Hazards Program, Communications and Publishing
Image: 2005 Landslide in Conchita, CA

2005 Landslide in Conchita, CA

2005 Landslide in Conchita, CA

This landslide occurred at La Conchita, California in 2005. Ten people were killed.

By
Natural Hazards Mission Area, Landslide Hazards Program, Communications and Publishing
Image: Oso, Washington Landslide
Oso, Washington Landslide
Oso, Washington Landslide
Image: Oso, Washington Landslide

Oso, Washington Landslide

Oso, Washington Landslide

Oblique aerial photograph of the Oso, Washington landslide, showing the entire extent of the landslide source area and path.

Location: State Route 530, Oso, Washington

By
Natural Hazards Mission Area, Landslide Hazards Program, Communications and Publishing
Image: Oso, Washington Landslide

Oso, Washington Landslide

Oso, Washington Landslide

Oblique aerial photograph of the Oso, Washington landslide, showing the entire extent of the landslide source area and path.

Location: State Route 530, Oso, Washington

By
Natural Hazards Mission Area, Landslide Hazards Program, Communications and Publishing
Filter Total Items: 41

Shear surface undulations modulate clayey gouge strength and contribute to divergent landslide acceleration Shear surface undulations modulate clayey gouge strength and contribute to divergent landslide acceleration

Landslides display a spectrum of speeds for incompletely known reasons. Sliding occurs along slickensided undulatory shear surfaces within boundary shear gouge. Laboratory tests reveal that gouge shear strength generally decreases with finite cumulative displacement during relatively rapid failure and may increase or decrease with increasing shear rate; these behaviors can result in...
Authors
William H. Schulz, Gonghui Wang, Yao Jiang, Brian D. Collins, Mark E. Reid, Mason Muir Einbund
By
Geologic Hazards Science Center

Topographic controls on landslide mobility: Modeling hurricane-induced landslide runout and debris-flow inundation in Puerto Rico Topographic controls on landslide mobility: Modeling hurricane-induced landslide runout and debris-flow inundation in Puerto Rico

In 2017, Hurricane Maria triggered more than 70 000 landslides in Puerto Rico. After initiation, these predominantly shallow landslides were mobilized to varying extents – some landslides only traveled partway downslope, whereas others reached drainage channels and were mobilized into long-traveled debris flows that could severely impact roads and infrastructure. Thus, forecasting...
Authors
Dianne L. Brien, Mark E. Reid, Collin Cronkite-Ratcliff, Jonathan P. Perkins
By
Volcano Hazards Program, Volcano Science Center

Grfin Tools—User guide and methods for modeling landslide runout and debris-flow growth and inundation Grfin Tools—User guide and methods for modeling landslide runout and debris-flow growth and inundation

The software package, Grfin Tools, can estimate potential runout from landslides or inundation from geophysical mass flows such as debris flows, lahars from volcanoes, and rock avalanches within a digital elevation model (DEM). Grfin is an acronym of growth + flow + inundation. The tools within this package apply simple, well-tested, empirical models of runout that are computationally...
Authors
Mark E. Reid, Dianne L. Brien, Collin Cronkite-Ratcliff, Jonathan P. Perkins
By
Natural Hazards Mission Area, Landslide Hazards Program, Volcano Hazards Program, Volcano Science Center

Assessing locations susceptible to shallow landslide initiation during prolonged intense rainfall in the Lares, Utuado, and Naranjito municipalities of Puerto Rico Assessing locations susceptible to shallow landslide initiation during prolonged intense rainfall in the Lares, Utuado, and Naranjito municipalities of Puerto Rico

Hurricane Maria induced about 70 000 landslides throughout Puerto Rico, USA, including thousands each in three municipalities situated in Puerto Rico's rugged Cordillera Central range. By combining a nonlinear soil-depth model, presumed wettest-case pore pressures, and quasi-three-dimensional (3D) slope-stability analysis, we developed a landslide susceptibility map that has very good...
Authors
Rex L. Baum, Dianne L. Brien, Mark E. Reid, William H. Schulz, Matthew J. Tello
By
Natural Hazards Mission Area, Landslide Hazards Program, Geologic Hazards Science Center

Lateral edifice collapse and volcanic debris avalanches: A post-1980 Mount St. Helens perspective Lateral edifice collapse and volcanic debris avalanches: A post-1980 Mount St. Helens perspective

The 1980 eruption of Mount St. Helens was instrumental in advancing understanding of how volcanoes work. Lateral edifice collapses and the generation of volcanic debris avalanches were not widely recognized prior to that eruption, making assessment of their hazards and risks challenging. The proliferation of studies since 1980 on resulting deposits and evaluation of processes leading to...
Authors
Lee Siebert, Mark E. Reid
By
Volcano Hazards Program, Geology, Minerals, Energy, and Geophysics Science Center, Volcano Science Center

Using integrated growth to delineate debris-flow inundation Using integrated growth to delineate debris-flow inundation

Debris-flow volume is fundamental to mobility, yet many debris flows change volume as they travel. Growth can occur through diverse processes such as channel-bed entrainment, bank failures, aggregation of landslides, and coalescence of multiple flows. Integrating growth, either over upslope area or stream length, combines the effects of these growth processes and requires specification...
Authors
Mark E. Reid, Dianne L. Brien, Collin Cronkite-Ratcliff, Jonathan P. Perkins
By
Volcano Hazards Program, Geology, Minerals, Energy, and Geophysics Science Center, Volcano Science Center

Grfin Tools—Software Package and Runtime Documentation for Users Grfin Tools—Software Package and Runtime Documentation for Users

Grfin Tools (an acronym of Growth + flow + inundation) is a set of software tools for portraying areas potentially impacted by runout from landslides or inundation from geophysical mass-flows (such as debris flows) with or without growth as they travel. Grfin Tools allows users to assess the effects of a wide range of factors that can influence mobility. The software also enables runout
By
Landslide Hazards Program, Geology, Minerals, Energy, and Geophysics Science Center
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