Unified Interior Regions


The Southwest Region includes California, Nevada, and Arizona. The Regional Office, headquartered in Sacramento, provides Center oversight and support, facilitates internal and external collaborations, and works to further USGS strategic science directions.

States L2 Landing Page Tabs

Filter Total Items: 140
Date published: October 24, 2018
Status: Active

Cassini Observations of Io's Visible Aurorae

As the Cassini spacecraft passed through the Jovian system on its way to Saturn, it captured more than 500 images of Jupiter's moon Io in eclipse. Cassini's near-ultraviolet filters detected the moon's bright equatorial glows, supporting the interpretation that the visible emissions are predominantly due to molecular sulfer dioxide (SO2).

Date published: October 24, 2018
Status: Active

Laboratory Infrared Spectroscopy of Mars Analog Materials

Former USGS scientist, Jeff Johnson, performed key research on the detection of dust on the Martian surface. This work explored the laboratory thermal infrared and visible/near-infrared spectroscopy of palagonitic dust coatings on rock substrates and experimentally shocked feldspars and pyroxenes.

Date published: October 22, 2018
Status: Active

Three Decades of Martian Surface Changes

The surface of Mars has changed dramatically during the three decades spanned by spacecraft exploration. Comparisons of Mars Global Surveyor images with Viking and Mariner 9 pictures suggest that more than one third of Mars' surface area has brightened or darkened by at least 10%. 

Date published: October 22, 2018
Status: Active

Valles Marineris - The Grand Canyon of Mars

The Valles Marineris is a system of canyons located just south of the Martian equator. The system is about 4000 km long, and, if on earth, would extend all the way across the United States. The central individual troughs, generally 50 to 100 km wide, merge into a depression as much as 600 km wide. In places the canyon floor reaches a depth of 10 km, 6 to 7 times deeper than...

Date published: October 22, 2018
Status: Active

Sub-ice Volcanism on Earth and Mars

Sub-glacially erupted volcanoes form free-standing flat-topped mesas, known as tuyas. Although there are some silicic edifices (e.g. Tuffen et al., 2002), most terrestrial sub-ice volcanoes are mafic and consist of horizontal layered basaltic lavas overlying friable flank deposits of steeply-dipping (angled) hyaloclastite breccias composed of variably-altered fine-grained...

Date published: October 22, 2018
Status: Active

Venus Magellan Impact Crater Database

The NASA Magellan spacecraft provided synthetic aperture radar (SAR) image coverage of 98% of the surface of the planet Venus, in addition to topography and several types of physical property data on the venusian surface (e.g., radar reflectivity, radar backscatter, emissivity, and rms slopes).(See Special Magellan Issue of J. Geophys. Res., v. 97, nos. E8 and E10, August 25...

Date published: October 22, 2018
Status: Active

Mars MER Microscopic Imager Surface Findings

The Microscopic Imagers (MI) on the Mars Exploration Rovers, Spirit and Opportunity, have returned images of Mars with higher resolution than any previous camera system, allowing detailed petrographic and sedimentological studies of the rocks and soils. Designed to simulate a geologist’s hand lens, the MI cameras were mounted on the rovers’ instrument arms. They can resolve...

Date published: October 19, 2018
Status: Archived

Moon Pyroclastic Volcanism Project

The products of explosive or pyroclastic volcanic eruptions on the Moon have intrigued lunar scientists for years. These deposits, nearly 100 in number and spread widely across the lunar surface, are generally dark and smooth-surfaced. Although pyroclastic materials were found in all lunar samples and thus they are known to be widely dispersed from their sources, the dark...

Date published: October 19, 2018
Status: Active

Revisiting Lava Flow Simple Models

Simple models relating the final dimensions of a lava flow to eruption parameters an lava rheology were used extensively in the 1980's but have fallen out of use in the terrestrial vocanology community. However, in the planetary volcanology community these models have had a resurgence of utilization, especially in response to the availability of high resolution topographic...

Date published: October 19, 2018
Status: Active


International Planetary Caves Conference 

Date published: October 17, 2018
Status: Active

Planetary Caves

As USGS scientist and planetary cave enthusiast, Glen Cushing, points out, "Caves are important to the future of planetary exploration because they are believed to provide shelter from a range of harsh surface conditions, maintaining near-pristine surfaces and relatively stable microclimates." See links on this page to explore further.

Date published: October 10, 2018
Status: Active

Shoemaker Sample Collection

The USGS Shoemaker Collection consists of unique and irreplaceable geologic hand samples, rock powders, petrographic thin sections and billets, and associated documentation, from impact craters and terrestrial analog sites around the world. Current curation efforts are focused on data rescue, preservation, and inventory. All geologic materials are being relocated into...

Filter Total Items: 60
Date published: April 19, 2016

The United States Interagency Elevation Inventory (USIEI)

The USIEI is a comprehensive, nationwide listing of known high-accuracy topographic and bathymetric data for the United States and its territories. The project is a collaborative effort of the USGS and NOAA with contributions from other federal agencies. The inventory supports the 3D Elevation Program and the Integrated Ocean and Coastal Mapping effort. This resource is updated in Spring and...

Date published: April 19, 2016

Elevation Data

The 3DEP products and services available through The National Map consist of lidar point clouds (LPC), standard digital elevation models (DEMs) at various horizontal resolutions, elevation source and associated datasets, an elevation point query service and bulk point query service. All 3DEP products are available, free of charge and without use restrictions.

Date published: April 12, 2016

Orthoimagery Data

Orthoimagery data typically are high resolution aerial images that combine the visual attributes of an aerial photograph with the spatial accuracy and reliability of a planimetric map. The National Map offers public domain, 1-meter orthoimagery for the conterminous United States with many urban areas and other locations at 2-foot or finer resolution.

Date published: April 12, 2016

The National Map Small-Scale Collection

The National Map offers a collection of small-scale datasets, most of which are at 1:1,000,000. The National Map publishes two data collections at one million-scale: one for Global Map users and one for National Map users. In terms of vector geometry, the lines, points, and areas in these data collections are identical. The difference is in the attributes assigned to these features.

Date published: April 6, 2016

Digital map of hydrothermal alteration type, key mineral groups, and green vegetation of the northwestern United States derived from automated analysis of ASTER satellite data

Mineral groups identified through automated analysis of remote sensing data acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) were used to generate a map showing the type and spatial distribution of hydrothermal alteration, other exposed mineral groups, and green vegetation across the northwestern conterminous United States. Boolean algebra was used to

Date published: March 12, 2016


WaterWatch is a U.S. Geological Survey (USGS) World Wide Web site that displays maps, graphs, and tables describing real-time, recent, and past streamflow conditions for the United States. The real-time information generally is updated on an hourly basis.

Date published: March 4, 2016

Current Alerts for U.S. Volcanoes

Volcano-alert notifications are produced by Volcano Observatory scientists based on analysis of data from monitoring networks, direct observations, and satellite sensors. They are issued for both increasing and decreasing volcanic activity and include text about the nature of the unrest or eruption and about potential or current hazards and likely outcomes.

Date published: January 1, 2016

Total Mercury Concentrations in Fish Muscle from the Colorado River and Bright Angel Creek, AZ, USA (2015)

This dataset contains data on the length, mass, and muscle total mercury concentration of Brown Trout (Salmo trutta) and Rainbow Trout (Oncorhynchus mykiss) collected from the Colorado River in Glen Canyon National Recreation Area (GLCA) and Grand Canyon National Park (GRCA), and Bright Angel Creek in GRCA.

Date published: November 23, 2013

Land Treatment Digital Library (LTDL)

The Land Treatment Digital Library (LTDL) was created by the USGS to catalog legacy land treatment information on Bureau of Land Management lands in the western United States. The LTDL can be used by federal managers and scientists for compiling information for data-calls, producing maps, generating reports, and conducting analyses at varying spatial and temporal scales.

Date published: July 24, 2013

Data Entry Module for the Land Treatment Digital Library (LTDL)

This software allows agencies, organizations, and individuals to download an empty, stand-alone Land Treatment Digital Library database to individual or networked computers. Data entered in these databases may be submitted to the USGS for possible inclusion in the online Land Treatment Digital Library (https://ltdl.wr.usgs.gov).

Date published: June 11, 2010

Oil and Gas Well locations, Upper Colorado River Basin, 2007

This dataset was used as the basis for estimating land disturbance from oil and gas activity in the UCRB. The dataset is a compilation of five state oil and gas datasets from June of 2007. The intended uses of this data set include, but are not limited to, natural resource modeling, mapping, and visualization applications.

Filter Total Items: 240
Pink Sand Dunes in Utah
February 27, 2018

Pink Dune

This is a photo of a pink sand dune in Utah.

USGS hydrographer collecting a suspended-sediment water sample from the highly turbid Little Colorado River in the Grand Canyon.
February 26, 2018

USGS hydrographer collecting a suspended-sediment water sample.

Suspended-Sediment Sampling and Turbidity

Here, a U.S. Geological Survey (USGS) hydrographer is collecting a suspended-sediment water sample from the Little Colorado River, a kilometer upstream from the Colorado River, Grand Canyon, Arizona, USA. To gain knowledge of the

February 22, 2018

Ungulates in a Warmer Climate

Researchers supported by NCCWSC are working to improve managers’ understanding of ungulates’ response to a warmer climate. For example, when surface water is unavailable, the water content within ungulates’ food provides them with their main source of water, and they must make resourceful foraging decisions to meet their water needs. Scientists researching desert bighorn

Lake Powell
December 31, 2017

Lake Powell

The USGS Utah Water Science Center and the Woods Hole Coastal and Marine Science Center conducted a collaborative geophysical research effort within Lake Powell, UT-AZ to map the bathymetry of the lake and characterize shallow sediment deposition near the mouths of the San Juan and Colorado Rivers.

A discussion group looks at notes on a large easel pad
December 31, 2017

Collaborative Discussion

The USGS RAMPS program hosts workshops where land managers from federal, state, and local agencies, practitioners, and NGO's can come together to discuss challenges and develop creative solutions. Here,

Digital elevation model created by an Unmanned Aerial System
December 31, 2017

Digital Elevation Model Created by an Unmanned Aerial System

This digital elevation model was created using structure from motion software mounted to an Unmanned Aerial System (UAS) to analyze bridge scour. Studies using UAS have included stream temperature analyses, bird and mammal surveys, coastal change mapping, sandbar habitat surveys, fluvial erosion rates, microclimate mapping, air quality analysis, plant stress assessment,

Close-up of dried, cracked soil with small plants trying to survive in this soil.
December 31, 2017

Dry, cracked soil (RAMPS)

Rangelands of the desert Southwest can be in a degraded condition and lacking perennial vegetation, which can lead to exposed soil and erosion. RAMPS is working to mitigate degradation by increasing 

Unmanned Aerial System prior to takeoff
December 31, 2017

Unmanned Aerial System

This small unmanned aerial system with digital camera has been used to create digital elevation models to answer questions about erosion, bridge scour, and other hydraulics analyses. 

Unmanned Aerial System takes images in Arizona
December 31, 2017

Unmanned Aerial System in Flight

Small Unmanned Aerial System (UAS) collecting digital photos to create digital elevation models. UAS are an increasingly important tool for monitoring, assessing, and conducting targeted scientific research for the nation.

December 17, 2017

USGS Astrogeology Geologic Map GIS Template

Review of all elements included in the GIS template provided to NASA-funded mappers producing USGS SIM-series planetary geologic maps.

November 30, 2017

Tour of the Planetary Geologic Mapping Python Toolbox

A tour of the Planetary Geologic Mapping Python toolbox, a suite of GIS tools from the Astrogeology Science Center.

Sonoran desert scene, complete with prickly pear, saguaro, and cholla cactus species.
October 31, 2017

Sonoran Desert Cactus Guild

The iconic Sonoran Desert is home to many species of cactus, vascular plants, and wildlife, including the giant saguaro, cholla, and prickley pear cacti seen here. Plants and animals have adapted to living in such a harsh dry environment. For example, the plants in this photo have grown up in the shade of one another, and survived due to protection from the hot sun. The

Filter Total Items: 192
Southwestern Willow Flycatcher
September 6, 2016

A new report by the U.S. Geological Survey shows, for the first time ever, detailed habitat information on the entire range of a federally listed endangered bird allowing officials to take a scientific approach to helping protect the species.

Photograph showing San Pedro Riparian National Conservation Area.
August 18, 2016

Streamflow and groundwater levels are declining in some locations along the San Pedro River near Sierra Vista, Arizona, according to a new report by the U.S. Geological Survey.

Photo of the Colorado River near Moab, Utah
August 15, 2016

Future groundwater replenishment in the Upper Colorado River Basin may benefit from projected increases in future basin-wide precipitation under current climate projections, according to a recent study by the U.S. Geological Survey and Bureau of Reclamation.

Four numbered sample jars containing brownish water and small snails in a laboratory connected to tubes and electronic meter.
August 4, 2016

To gain insights into the risks associated with uranium mining and processing, U.S. Geological Survey scientists are investigating how uranium moves into and up food chains.

May 25, 2016

Laura Norman was asked to provide a presentation at the Hassayampa River Study meeting. Stakeholders in the 3,700 km² watershed are interested in the benefits of hydrologic modeling to assess if stormwater management practices would impact stormflows, sedimentation, and groundwater recharge.

An image of Hi'iaka Montes and Hi'iaka Patera on Jupiter's volcanic moon Io.
May 19, 2016

Mountains on Io, Jupiter’s volcanic moon, are formed by a unique geologic mechanism not found elsewhere in the solar system, according to a new study by the U.S. Geological Survey.

Topographic Map of Mercury
May 6, 2016

The first topographic map of Mercury was released today by the U.S. Geological Survey, Arizona State University, Carnegie Institute of Washington, Johns Hopkins University Applied Physics Laboratory and NASA.

People collecting aquatic insects at night along the Colorado River.
May 2, 2016

Alternative Flows Might Mitigate Negative Impacts

Filter Total Items: 84