Tens of millions of people felt the M5.8 earthquake that occurred in Louisa County, VA on August 23, 2011. The earthquake occurred on a fault that had not previously been known, and no corresponding surface rupture was observed. To map the lateral extent of the fault and associated geologic structures, the USGS commissioned high-resolution airborne magnetic, gravity and radiometric (gamma-ray spectroscopy) as well as lidar surveys over the epicentral region.
Remote sensing technologies have become an important data source for the study of fire disturbance and recovery. Fire disturbance and variations in vegetation dynamics following fire are primary factors in shaping the patchwork nature of wetland vegetation/surface water cover. However, little is known about wetland post fire ecology.because research has occurred almost exclusively in upland environments, not wetlands. USGS is conducting research to improve methods for fire detection, fire scar mapping, burn severity indexing, and post fire vegetation monitoring in wetland environments.
The United States Geological Survey uses AVHRR satellite data and weather information to assess fuel conditions and create the Fire Potential Index (FPI) to identify areas most susceptible to fire ignition.
In 2011, the USGS completed the mapping of 1972 to 2007 historical wildfires in Lincoln and Clark counties of Nevada using Landsat data. This work resulted in the documentation of historical wildfire information related to burn perimeters, severity, frequency, and post fire vegetation characteristics that is useful to local, State, and Federal land managers in Nevada. In FY 2012, USGS will expand the historical wildfire database to the entire Mojave study area including several military reservations.
The USGS uses remote-sensing to map wildland fuels in the United States. USGS leads the Landscape Fire and Resource Management Planning Tools (LANDFIRE) which provides consistent and comprehensive maps and data describing vegetation, wildland fuel, and fire regimes across the United States. The LANDFIRE geospatial data are derived from Landsat satellite data and ecological models which provide layers of vegetation composition and structure, surface and canopy fuel characteristics, and historical fire regimes.
USGS scientists, in collaboration with EPA, are investigating the use of hyperspectral remote sensing for monitoring superfund hazardous waste sites. Hyperspectral imagery is a valuable tool, assisting with the identification and characterization of site status and morphological changes in site size and activity. Hazardous substances were identified from spectroscopic analysis of hyperspectral images acquired from the ARCHER airborne system and confirmed by laboratory analysis of on-site soil samples.
Using Landsat imagery, the Monitoring Trends and Burn Severity (MTBS) project delineates fire perimeters and estimates the severity of fire effects upon the landscape. All known large historical fires dating back to 1984 have been mapped by the USGS and the U.S.
Terrestrial lidar, or T-lidar, was deployed by the USGS in the immediate aftermath of Hurricane Isaac to map urban flooding and quickly generate 3-D maps of buildings, dams, levees and other structures that were damaged in the storm. For example, the Tangipahoa Dam near McComb, MS, was damaged during heavy rainfall in Hurricane Isaac and caused thousands of people in Tangipahoa Parish downstream to be evacuated. Using T-lidar, the crew captured multiple 3-D scans of the dam, including two large landslides on its downstream side and were able to estimate the size of the slides as well as m
Coastal wetlands are critical nursery areas for coastal and oceanic life are essential to ocean productivity.
Since 2003, USGS and the USFS provide burn severity mapping support to meet the requirements of Burn Area Emergency Response (BAER) Teams. BAER teams are mandated to quickly (2 weeks) evaluate the effects of wildfires and develop mitigation plans to protect valuable natural and man-made resources from landslides and to promote landscape recovery. Seven to 8 years ago, BAER teams relied upon sketch mapping to delineate severity patterns on topographic maps. Today, satellite imagery has largely replaced the manual methods for BAER teams.