This is an example of a lidar image created from the “point cloud” that shows objects’ reflectivity near the Santa Cruz Beach Boardwalk and the mouth of the San Lorenzo River.
Joshua Logan
Physical Scientist with the USGS Pacific Coastal and Marine Science Center
Science and Products
Topographic survey data and digital elevation model of Oxbow Reservoir, Placer County, California, October 2022
Rain measurements in and near the Dolan Fire Area, Los Padres National Forest, California, 2022 to 2023
Aerial imagery and structure-from-motion data products from UAS surveys of the beaches at Fort Stevens State Park, OR, and Cape Disappointment State Park, WA
3D bathymetric surfaces of low- and high-relief sites from the coral reef flat off Waiakane, Molokai
Structure-from-motion derived orthomosaic imagery and digital surface models (DSMs) from the intertidal region at Whale's Tail Marsh, South San Francisco Bay, CA
Time-series data of water surface elevation, waves, currents, temperature, and turbidity collected between November 2017 and March 2018 off the west coast of Maui, Hawaii, USA
Aerial imagery and structure-from-motion data products from a UAS survey of the Los Padres Reservoir delta, Carmel River valley, CA, 2017-11-01
River-channel topography, grain size, and turbidity records from the Carmel River, California, before, during, and after removal of San Clemente Dam (ver. 2.0, March 2022)
Aerial imagery and structure-from-motion-derived shallow water bathymetry from a UAS survey of the coral reef off Waiakane, Molokai, Hawaii, June 2018
Aerial imagery and structure-from-motion data products from UAS survey of the intertidal zone at Lone Tree Point, Kiket Bay, WA, June 2019
Aerial imagery and structure-from-motion data products from UAS survey of the intertidal zone at West Whidbey Island, WA, June 2019
Bathymetry, topography and orthomosaic imagery for Whiskeytown Lake, northern California (ver. 2.0, July 2021)
Colored shaded-relief bathymetric map and surrounding aerial imagery of Whiskeytown Lake, California
This is an example of a lidar image created from the “point cloud” that shows objects’ reflectivity near the Santa Cruz Beach Boardwalk and the mouth of the San Lorenzo River.
A digital still image can be overlaid onto the lidar “point cloud” data to give it a realistic 3D look.
A digital still image can be overlaid onto the lidar “point cloud” data to give it a realistic 3D look.
USGS Geographer Josh Logan sets up the lidar scanner near Capitola before the December 11, 2014 "Super Soaker" storm.
USGS Geographer Josh Logan sets up the lidar scanner near Capitola before the December 11, 2014 "Super Soaker" storm.
After dam removal on the Elwha River, the site of a previous survey had finer grained sediment. Surveyor in the distance is James Starr of the USGS Washington Water Science Center.
After dam removal on the Elwha River, the site of a previous survey had finer grained sediment. Surveyor in the distance is James Starr of the USGS Washington Water Science Center.
Lidar data collected in 2010 and 2012 showing a change in the beach profile. Spot marked by vertical arrow was about 1 meter (3 feet) higher after two years.
Lidar data collected in 2010 and 2012 showing a change in the beach profile. Spot marked by vertical arrow was about 1 meter (3 feet) higher after two years.
Combining field observations and high-resolution numerical modeling to demonstrate the effect of coral reef roughness on turbulence and its implications for reef restoration design
Wave-scale observations of sediment resuspension and subsequent transport across a fringing reef flat
Wave-scale observations of coarse-grained sediment resuspension and subsequent transport across a fringing reef flat, Molokaʻi, Hawaiʻi, USA
Observations of coastal circulation, waves, and sediment transport along West Maui, Hawaiʻi (November 2017– March 2018), and modeling effects of potential watershed restoration on decreasing sediment loads to adjacent coral reefs
Six years of fluvial response to a large dam removal on the Carmel River, California, USA
Watershed sediment yield following the 2018 Carr Fire, Whiskeytown National Recreation Area, northern California
Physicochemical controls on zones of higher coral stress where Black Band Disease occurs at Mākua Reef, Kauaʻi, Hawaiʻi
Characterizing the catastrophic 2017 Mud Creek Landslide, California, using repeat Structure-from-Motion (SfM) photogrammetry
Along the rugged coast of Big Sur, California, the Mud Creek landslide failed catastrophically on May 20, 2017 and destroyed over 400 m of scenic California State Highway 1. We collected structure-from-motion (SfM) photogrammetry data using airborne platforms that, when combined with existing airborne lidar data, revealed that the area exhibited significant topographic change and displacement befo
Geomorphic evolution of a gravel‐bed river under sediment‐starved vs. sediment‐rich conditions: River response to the world's largest dam removal
Understanding river response to sediment pulses is a fundamental problem in geomorphic process studies, with myriad implications for river management. However, because large sediment pulses are rare and usually unanticipated, they are seldom studied at field scale. We examine fluvial response to a massive (~20 Mt) sediment pulse released by the largest dam removal globally, on the Elwha River, Was
River response to large‐dam removal in a Mediterranean hydroclimatic setting: Carmel River, California, USA
Coastal circulation and water-column properties in the National Park of American Samoa, February–July 2015
Large-scale dam removal on the Elwha River, Washington, USA: river channel and floodplain geomorphic change
Agisoft Metashape/Photoscan Automated Image Alignment and Error Reduction version 2.0
Science and Products
- Data
Filter Total Items: 25
Topographic survey data and digital elevation model of Oxbow Reservoir, Placer County, California, October 2022
This data release presents topographic survey data and a digital elevation model (DEM) of Oxbow Reservoir, in Placer County, California. The U.S. Geological Survey (USGS) conducted a topographic survey of accessible regions of the reservoir sediment on 26 October 2022, when the reservoir was partially de-watered to allow repairs to the dam infrastructure following the Mosquito Fire. The survey wasRain measurements in and near the Dolan Fire Area, Los Padres National Forest, California, 2022 to 2023
Rainfall measurements were collected in and near the Dolan Fire burn area, Los Padres National Forest, California. The CZU Fire ignited in Los Padres National Forest, California, on August 18, 2020. By the time of full containment on December 31, 2020, the fire had burned 518 km2 (128,050 acres) in Monterey County. The U.S. Geological Survey (USGS) installed seven rain gages in and near the DolanAerial imagery and structure-from-motion data products from UAS surveys of the beaches at Fort Stevens State Park, OR, and Cape Disappointment State Park, WA
This data release presents aerial imagery and structure-from-motion (SfM) data products from uncrewed aerial system (UAS) surveys conducted on the ocean beaches adjacent to the Columbia River Mouth at the Oregon-Washington border. The surveys cover approximately 3 kilometers of Benson Beach at Cape Disappointment State Park north of the Columbia River mouth, in Washington, and 3 kilometers of the3D bathymetric surfaces of low- and high-relief sites from the coral reef flat off Waiakane, Molokai
3D bathymetric surfaces of low- and high-relief sites from the coral reef flat off Waiakane, Molokai, were created using structure-from-motion (SfM) techniques. The two study sites are located approximately 640 m from shore and approximately 20 m apart in the alongshore direction. At each site, an approximate 12-meter diameter area was imaged in three passes by a swimmer using a handheld digital cStructure-from-motion derived orthomosaic imagery and digital surface models (DSMs) from the intertidal region at Whale's Tail Marsh, South San Francisco Bay, CA
This data release presents digital surface models (DSMs) and orthomosaic images of the Whale's Tail Marsh region of South San Francisco Bay, CA. The data were created using structure-from-motion (SfM) processing of repeat aerial imagery collected from fixed-wing aircraft. The raw images were acquired from an approximate altitude of 427 meters (1,400 feet) above ground level (AGL), using a HasselblTime-series data of water surface elevation, waves, currents, temperature, and turbidity collected between November 2017 and March 2018 off the west coast of Maui, Hawaii, USA
Time-series data of water surface elevation, waves, currents, temperature, and turbidity collected between November 2017 and March 2018 off the west coast of Maui, Hawaii, USA. The data are available in NetCDF format, grouped together in zip files by instrument site location. These data support a modeling study on the effects of potential watershed restoration on decreasing sediment loads to adjacAerial imagery and structure-from-motion data products from a UAS survey of the Los Padres Reservoir delta, Carmel River valley, CA, 2017-11-01
An unoccupied aerial system (UAS) was used to acquire high-resolution imagery of the exposed reservoir delta at Los Padres Reservoir, in the Carmel River valley in central California on 1 November 2017. This survey followed sediment delivery to the reservoir by the Carmel River due to landscape response after the 2016 Soberanes Fire and high flows in winter 2017. The imagery from this survey was pRiver-channel topography, grain size, and turbidity records from the Carmel River, California, before, during, and after removal of San Clemente Dam (ver. 2.0, March 2022)
The San Clemente Dam, built in the 1920s on the Carmel River in Monterey County, California, was removed during 2014 and 2015. The dam-removal project was the largest in California to date, and one of the largest in the U.S. This USGS data release presents data collected before, during, and after the removal of the dam. The data were collected to study how the river channel's topographic profilesAerial imagery and structure-from-motion-derived shallow water bathymetry from a UAS survey of the coral reef off Waiakane, Molokai, Hawaii, June 2018
An unoccupied aerial system (UAS) was used to acquire high-resolution imagery of the shallow fringing coral reef at Waiakane, Molokai, Hawaii, on 24 June 2018. Imagery was acquired over an area between the shoreline and approximately 900 meters offshore, covering approximately 16 hectares. The imagery was processed using structure-from-motion (SfM) photogrammetric techniques with additional refracAerial imagery and structure-from-motion data products from UAS survey of the intertidal zone at Lone Tree Point, Kiket Bay, WA, June 2019
An unmanned aerial system (UAS) was used to acquire high-resolution imagery of the intertidal zone at Lone Tree Point, Kiket Bay, Washington on June 5, 2019. This imagery was processed using structure-from-motion (SfM) photogrammetric techniques to derive a high-resolution digital surface model (DSM), orthomosaic imagery, and topographic point clouds. In order to maximize the extent of the subaAerial imagery and structure-from-motion data products from UAS survey of the intertidal zone at West Whidbey Island, WA, June 2019
An unmanned aerial system (UAS) was used to acquire high-resolution imagery of the intertidal zone at West Whidbey Island, Washington on June 4, 2019. This imagery was processed using structure-from-motion (SfM) photogrammetric techniques to derive a high-resolution digital surface model (DSM), orthomosaic imagery, and topographic point clouds. In order to maximize the extent of the subaeriallyBathymetry, topography and orthomosaic imagery for Whiskeytown Lake, northern California (ver. 2.0, July 2021)
The Carr Fire ignited in northern California on July 23, 2018, and over the following six weeks burned almost 300,000 acres (approximately half on federal lands), resulting in a federal major-disaster declaration (DR-4382). Approximately 93 percent of the area within Whiskeytown National Recreation Area was burned extensively during the Carr Fire, including all of the landscape surrounding and dra - Maps
Colored shaded-relief bathymetric map and surrounding aerial imagery of Whiskeytown Lake, California
The Carr wildfire began on July 23, 2018, and burned almost 300,000 acres (approximately half on Federal lands) in northern California during the subsequent 6-week period. Over 97 percent of the area within Whiskeytown National Recreation Area, California, burned during the 2018 Carr wildfire, including the entire landscape that surrounds and drains into Whiskeytown Lake. Shortly after the Carr wi - Multimedia
Lidar image from point cloud
This is an example of a lidar image created from the “point cloud” that shows objects’ reflectivity near the Santa Cruz Beach Boardwalk and the mouth of the San Lorenzo River.
This is an example of a lidar image created from the “point cloud” that shows objects’ reflectivity near the Santa Cruz Beach Boardwalk and the mouth of the San Lorenzo River.
Lidar point cloud with digital still image overlayLidar point cloud with digital still image overlayA digital still image can be overlaid onto the lidar “point cloud” data to give it a realistic 3D look.
A digital still image can be overlaid onto the lidar “point cloud” data to give it a realistic 3D look.
LidarUSGS Geographer Josh Logan sets up the lidar scanner near Capitola before the December 11, 2014 "Super Soaker" storm.
USGS Geographer Josh Logan sets up the lidar scanner near Capitola before the December 11, 2014 "Super Soaker" storm.
Surveying Elwha River bankAfter dam removal on the Elwha River, the site of a previous survey had finer grained sediment. Surveyor in the distance is James Starr of the USGS Washington Water Science Center.
After dam removal on the Elwha River, the site of a previous survey had finer grained sediment. Surveyor in the distance is James Starr of the USGS Washington Water Science Center.
Lidar data shows change in beach profileLidar data collected in 2010 and 2012 showing a change in the beach profile. Spot marked by vertical arrow was about 1 meter (3 feet) higher after two years.
Lidar data collected in 2010 and 2012 showing a change in the beach profile. Spot marked by vertical arrow was about 1 meter (3 feet) higher after two years.
- Publications
Filter Total Items: 14
Combining field observations and high-resolution numerical modeling to demonstrate the effect of coral reef roughness on turbulence and its implications for reef restoration design
Coral reefs are effective natural barriers that protect adjacent coastal communities from hazards such as erosion and storm-induced flooding. However, the degradation of coral reefs compromises their ability to protect against these hazards, making degraded reefs a target for restoration. There have been limited field and numerical modeling studies conducted to understand how an increase in coralAuthorsBenjamin K Norris, Curt Storlazzi, Andrew W. M. Pomeroy, Kurt J. Rosenberger, Joshua B. Logan, Olivia CheritonWave-scale observations of sediment resuspension and subsequent transport across a fringing reef flat
During a 3-month deployment on a broad, fringing reef flat in Moloka’i, Hawai’i, we observed over 28,000 wave-driven resuspension (WDR) events of coarse-grained sediment in order to identify major factors. These events were short-lived (2-11 s) and distinct from the longer-duration patterns of water-column backscatter. The wave-driven transport of WDR events was onshore, but the net cross-shore trAuthorsOlivia Cheriton, Curt Storlazzi, Kurt J. Rosenberger, Joshua B. Logan, Andrew W. M. Pomeroy, Mark L. Buckley, Jeff E. Hansen, Ryan J. LoweWave-scale observations of coarse-grained sediment resuspension and subsequent transport across a fringing reef flat, Molokaʻi, Hawaiʻi, USA
During a 3-month deployment on a broad, fringing reef flat in Moloka’i, Hawai’i, we observed over 28,000 wave-driven resuspension (WDR) events of coarse-grained sediment in order to identify major factors. These events were short-lived (2-11 s) and distinct from the longer-duration patterns of water-column backscatter. The wave-driven transport of WDR events was onshore, but the net cross-shore trAuthorsOlivia Cheriton, Curt Storlazzi, Kurt J. Rosenberger, Joshua B. Logan, Andrew W. M. Pomeroy, Mark L. Buckley, Jeff E. Hansen, Ryan J. LoweObservations of coastal circulation, waves, and sediment transport along West Maui, Hawaiʻi (November 2017– March 2018), and modeling effects of potential watershed restoration on decreasing sediment loads to adjacent coral reefs
Terrestrial sediment discharging from watersheds off West Maui, Hawaiʻi, has been documented as a primary stressor to local coral reefs, causing coral reef health to decline. The U.S. Geological Survey acquired and analyzed physical oceanographic and sedimentologic field data off the coast of West Maui to calibrate and validate physics-based, numerical hydrodynamic and sediment transport models ofAuthorsCurt D. Storlazzi, Olivia M. Cheriton, Katherine M. Cronin, Luuk H. van der Heijden, Gundula Winter, Kurt J. Rosenberger, Joshua B. Logan, Robert T. McCallSix years of fluvial response to a large dam removal on the Carmel River, California, USA
Measuring river response to dam removal affords a rare, important opportunity to study fluvial response to sediment pulses on a large field scale. We present a before–after/control–impact study of the Carmel River, California, measuring fluvial geomorphic and grain-size evolution over 8 years, six of which postdated removal of a 32 m-high dam (one of the largest dams removed worldwide) and includeAuthorsAmy E. East, Lee R. Harrison, Douglas P. Smith, Joshua B. Logan, Rosealea BondWatershed sediment yield following the 2018 Carr Fire, Whiskeytown National Recreation Area, northern California
Wildfire risk has increased in recent decades over many regions, due to warming climate and other factors. Increased sediment export from recently burned landscapes can jeopardize downstream infrastructure and water resources, but physical landscape response to fire has not been quantified for some at-risk areas, including much of northern California, USA. We measured sediment yield from three watAuthorsAmy E. East, Joshua B. Logan, Peter Dartnell, Oren Lieber-Kotz, David B. Cavagnaro, Scott W. McCoy, Donald N. LindsayPhysicochemical controls on zones of higher coral stress where Black Band Disease occurs at Mākua Reef, Kauaʻi, Hawaiʻi
Pervasive and sustained coral diseases contribute to the systemic degradation of reef ecosystems, however, to date an understanding of the physicochemical controls on a coral disease event is still largely lacking. Water circulation and residence times and submarine groundwater discharge all determine the degree to which reef organisms are exposed to the variable chemistry of overlying waters; undAuthorsFerdinand Oberle, Curt D. Storlazzi, Olivia Cheriton, Renee K. Takesue, Daniel J. Hoover, Joshua B. Logan, Christina M. Runyon, Christina A. Kellogg, Cordell Johnson, Peter W. SwarzenskiCharacterizing the catastrophic 2017 Mud Creek Landslide, California, using repeat Structure-from-Motion (SfM) photogrammetry
Along the rugged coast of Big Sur, California, the Mud Creek landslide failed catastrophically on May 20, 2017 and destroyed over 400 m of scenic California State Highway 1. We collected structure-from-motion (SfM) photogrammetry data using airborne platforms that, when combined with existing airborne lidar data, revealed that the area exhibited significant topographic change and displacement befo
AuthorsJonathan Warrick, Andrew C. Ritchie, Mark E. Reid, Kevin M. Schmidt, Joshua B. LoganGeomorphic evolution of a gravel‐bed river under sediment‐starved vs. sediment‐rich conditions: River response to the world's largest dam removal
Understanding river response to sediment pulses is a fundamental problem in geomorphic process studies, with myriad implications for river management. However, because large sediment pulses are rare and usually unanticipated, they are seldom studied at field scale. We examine fluvial response to a massive (~20 Mt) sediment pulse released by the largest dam removal globally, on the Elwha River, Was
AuthorsAmy E. East, Joshua B. Logan, Mark C. Mastin, Andrew C. Ritchie, Jennifer A. Bountry, Christopher S. Magirl, Joel B. SankeyRiver response to large‐dam removal in a Mediterranean hydroclimatic setting: Carmel River, California, USA
Dam removal provides a valuable opportunity to measure the fluvial response to changes in both sediment supply and the processes that shape channel morphology. We present the first study of river response to the removal of a large (32‐m‐high) dam in a Mediterranean hydroclimatic setting, on the Carmel River, coastal California, USA. This before‐after/control‐impact study measured changes in channeAuthorsLee R. Harrison, Amy E. East, Douglas P. Smith, Joshua B. Logan, Rosealea Bond, Colin L. Nicol, Thomas H. Williams, David A. Boughton, Kaitlyn Chow, Lauren LunaCoastal circulation and water-column properties in the National Park of American Samoa, February–July 2015
There is little information on the oceanography in the National Park of American Samoa (NPSA). The transport pathways for potentially harmful constituents of land-derived runoff, as well as larvae and other planktonic organisms, are driven by nearshore circulation patterns. To evaluate the processes affecting coral reef ecosystem health, it is first necessary to understand the oceanographic procesAuthorsCurt D. Storlazzi, Olivia Cheriton, Kurt J. Rosenberger, Joshua B. Logan, Timothy B. ClarkLarge-scale dam removal on the Elwha River, Washington, USA: river channel and floodplain geomorphic change
A substantial increase in fluvial sediment supply relative to transport capacity causes complex, large-magnitude changes in river and floodplain morphology downstream. Although sedimentary and geomorphic responses to sediment pulses are a fundamental part of landscape evolution, few opportunities exist to quantify those processes over field scales. We investigated the downstream effects of sedimenAuthorsAmy E. East, George R. Pess, Jennifer A. Bountry, Christopher S. Magirl, Andrew C. Ritchie, Joshua B. Logan, Timothy J. Randle, Mark C. Mastin, Justin Toby Minear, Jeffrey J. Duda, Martin C. Liermann, Michael L. McHenry, Timothy J. Beechie, Patrick B. Shafroth - Software
Agisoft Metashape/Photoscan Automated Image Alignment and Error Reduction version 2.0
This repository contains python scripts which automate image alignment and sparse point cloud error reduction in the Agisoft Metashape/Photoscan structure from motion photogrammetry software package using the Agisoft Metashape Python API. The current version of the script (version 2.0) approximates the workflow described in U.S. Geological Survey Open-File Report 2021-1039 (Over et al., 2021). The - News