Unified Interior Regions

Arizona

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: November 14, 2018
Status: Completed

Mars Ice

The Mars-Ice project is a joint project between the USGS Astrogeology Research Program (Flagstaff, AZ) and the Arizona State University Mars Space Flight Facilty (Tempe, AZ) to bring together a single resource for the exploration of martian ices. Much of this research is done at the USGS Flagstaff Science Center.

Date published: November 14, 2018
Status: Completed

Data And Instruments

Data and Instruments

Date published: November 14, 2018
Status: Completed

The Mars Global Digital Dune Database

The Mars Global Digital Dune Database (MGD3)

The Mars Global Digital Dune Database (MGD3)was compiled and released in three parts, encompassing the area from latitude 65°N to 65°S, from 60°N to 90°N (the north polar region), and from 60° to 90°S (south polar region). All the remote sensing data for both GIS and non-GIS users is available online in three U.S. Geological Survey...

Date published: November 14, 2018
Status: Completed

Mars Dune Image Galleries

Mars Dune Image Galleries: CRISM, THEMIS, MOC and HiRISE

Date published: November 14, 2018
Status: Completed

Dune Classification

A detailed classification system for Martian dunes is currently in the works. However, we have summarized current classifications below. You can find more information on terrestrial dune classification by clicking here.

Date published: November 9, 2018
Status: Completed

Consortium Announcements and Meetings

Consortium hosted meetings will be listed below. If you would like to attend any of these meetings, please be sure to register. Should your plans change after you register, you may simply reregister with your changes detailed appropriately.

Date published: November 9, 2018
Status: Completed

Workshops

Researchers in the planetary and terrestrial aeolian community are at work all over the world; the last workshop alone had representatives from eight countries and three continents! This research is conducted locally on Earth analogs and on such far-flung places as Titan, but the common goal is to understand geological processes on the rocky planets, dwarf planets, asteroids,...

Date published: November 9, 2018
Status: Active

Announcements

Mars Dunes Announcements

Date published: November 9, 2018
Status: Completed

Mars Dunes

Sand dunes are among the most widespread aeolian features present on Mars, serving as unique indicators of the interaction between the atmosphere and surface. On a planetary body, dunes accumulate where a supply of sand-sized grains exists or may be abraded, is carried downwind by winds of saltation strength, and is subsequently deposited where these winds weaken below the...

Date published: October 24, 2018
Status: Active

Aquifer-Storage Change and Land-Surface Elevation Change Monitoring in the Tucson Active Management Area

The Arizona Water Science Center is monitoring aquifer-storage changes and land subsidence within the Tucson Active Management Area (AMA). Land-surface elevation change is monitored at a network of benchmarks throughout the Tucson AMA by measuring changes in land surface elevation over time (approximately annually) with Interferometric Synthetic Aperture Radar (InSAR).  Aquifer-storage change...

Date published: October 24, 2018
Status: Active

MER MI Products

A single MI image or an Microscopic Imager mosaic can be merged with Pancam color images. The two products must be coregistered first, and then added together to produce colorized images in which the intensity comes from the MI and color (hue/saturation) comes from the Pancam images. This method of colorizing data may not yield a satisfactory product if the solar illumination...

Date published: October 24, 2018
Status: Active

Evidence of Cryovolcanism on Titan

The Cassini RADAR team led by USGS scientist, Randolph Kirk, has discovered the "best candidate yet" for an ice volcano on Saturn's moon Titan. The 3D view reveals multiple mountain peaks, deep pits and finger-like flows at Sotra Facula. Some of the terrain resembles volcanic cones, craters and flows on Earth but made of Titan materials (ice and/or carbon compounds) not molten...

Filter Total Items: 59
Date published: September 21, 2017

Habitat Data for Arizona Grasshopper Sparrow Territories, Nest Plots, and Random Transects, 2009 to 2013

These data provide information about vegetation structure and composition associated with Arizona Grasshopper Sparrow territories, nest plots, and random transects on two study sites in southeastern Arizona. Data were collected from 2009 through 2013.

Date published: September 1, 2017

National Water Information System web interface (NWISweb)

The National Water Information System (NWIS) web application provides access to real-time and historical surface-water, groundwater, water-quality, and water-use data collected at approximately 1.5 million sites across all 50 states.

Date published: August 25, 2017

Roadside Survey Data from southeastern Arizona and New Mexico for Grasshopper Sparrow and other grassland Birds 2003 to 2005

These data include descriptions of all roadside segments surveyed, including GPS waypoints and verbal descriptions for each point (every half mile), survey data collected on roadside surveys in 2003-2005 in the months of July and August, along roads within the known breeding range of the Arizona Grasshopper Sparrow (Ammodramus savannarum ammolegus).

Date published: July 6, 2017

Life history attributes data for Arizona Grasshopper Sparrow (Ammodramus savannarum ammolegus) in Arizona 2013

The Arizona Grasshopper Sparrow (Ammodramus savannarum ammolegus) occurs in the desert and plains grasslands of southeastern Arizona, southwestern New Mexico, and northern Sonora, Mexico. This data was produced as part of the first intensive study of its life history and breeding ecology, providing baseline data and facilitating comparisons with other North American Grasshopper Sparrow...

Date published: April 1, 2017

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 7, 2017

Catchment-flowline network and selected model inputs for an enhanced and updated spatially referenced statistical assessment of dissolved-solids load sources and transport in streams of the Upper Colorado River Basin

This USGS data release consists of the synthetic stream network and associated catchments used to develop spatially referenced regressions on watershed attributes (SPARROW) model of dissolved-solids sources and transport in the Upper Colorado River Basin as well as geology and selected Basin Characterization Model (BCM) data used as input to the model.

Date published: January 27, 2017

Mean of the Top Ten Percent of NDVI Values in the Yuma Proving Ground during Monsoon Season, 1986-2011

This study uses growth in vegetation during the monsoon season measured from LANDSAT imagery as a proxy for measured rainfall. NDVI values from 26 years of pre- and post-monsoon season Landsat imagery were derived across Yuma Proving Ground (YPG) in southwestern Arizona, USA.

Date published: January 1, 2017

USGS Southwest Repeat Photography Collection: Kanab Creek, southern Utah and northern Arizona, 1872-2010

The USGS Southwest Repeat Photography Collection (‘Collection’), formerly named the Desert Laboratory Repeat Photography Collection, is now housed by the Southwest Biological Science Center (SBSC) in Flagstaff, Arizona. It contains images from the late 1800s to mid-2000s, and was assembled over decades by now retired USGS scientists Drs. Robert H. Webb and Raymond

Date published: August 4, 2016

Prospect- and Mine-Related Features from U.S. Geological Survey 7.5- and 15-Minute Topographic Quadrangle Maps of the Western United States

These data are part of a larger USGS project to develop an updated geospatial database of mines, mineral deposits and mineral regions in the United States. Mine and prospect-related symbols, such as those used to represent prospect pits, mines, adits, dumps, tailings, etc., hereafter referred to as “mine” symbols or features, are currently being digitized on a st

Date published: April 20, 2016

Structures Data

USGS data portray selected structures data, including the location and characteristics of manmade facilities. Characteristics consist of a structure's physical form (footprint), function, name, location, and detailed information about the structure. The types of structures collected are largely determined by the needs of the disaster planning and response and homeland security organizations....

Filter Total Items: 44
RPIF Logo
September 24, 2018

The Astrogeology RPIF maintains and distributes a stock of some 60,000 lunar and planetary maps generated since about 1960. The approximately 900 individual maps published since 1961 in the USGS lunar and planetary I-Map/SIM-map series are listed in an Excel spreadsheet (below). Many of these maps are available in hardcopy form at no cost to the requestor. 

RPIF Inventory

A stretch of the Colorado River in the Grand Canyon with rock formations partially covered by clouds. 
January 23, 2017

This web mapping application provides access to many of Grand Canyon Monitoring and Research Center’s most commonly used map layers in support of science efforts occurring throughout the Colorado River corridor.

Figure 6 for Southwestern Willow Flycatcher Habitat Viewer webpage
August 8, 2016

Figure 6. Map showing changes in predicted flycatcher habitat along the upper Gila River after conducting a tamarisk leaf beetle-impact simulation. The upper Gila River was divided into nine zones in order to quantify changes. A satellite model was used to predict flycatcher habitat at a 40-percent probability threshold.

Figure 5 for Southwestern Willow Flycatcher Habitat Viewer webpage
August 8, 2016

Figure 5. Map showing changes in predicted flycatcher habitat along the lower Virgin River, Nevada and Arizona, 2010–2015, as determined from a satellite model at a 40-percent probability threshold.

Figure 3 for Southwestern Willow Flycatcher Habitat Viewer webpage
August 8, 2016

Map showing relative changes in predicted flycatcher habitat, as determined from a satellite model at a 40-percent probability threshold, Southwestern United States, 2013–15.

Figure 2 for Southwestern Willow Flycatcher Habitat Viewer webpage
August 8, 2016

Map showing area of predicted flycatcher breeding habitat (averaged across 2013–15) at all elevations in 6,521 U.S. Geological Survey 7.5-minute quadrangles, Southwestern United States. Only areas within a prescribed distance of streams and greater than stream-order 3, or within 1 kilometer of a lake or reservoir, were included in this analysis.

Figure 1 for Southwestern Willow Flycatcher Habitat Viewer webpage
August 8, 2016

Figure 1. Maps showing location of the project area and the 35 U.S. Fish and Wildlife Service Southwestern Willow Flycatcher management unit boundaries, designated critical-habitat reaches, and waterbodies considered by the satellite model for regionwide modeling, Southwestern United States.

Digital Elevation Model in the Atchafalaya Basin, LA
April 19, 2016

The 3DEP products and services available through The National Map consist of 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.

Filter Total Items: 127
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Year Published: 2000

Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona: 1998

The Black Mesa monitoring program is designed to document long-term effects of ground-water pumping from the N aquifer by industrial and municipal users. The N aquifer is the major source of water in the 5,400-square-mile Black Mesa area, and the ground water occurs under confined and unconfined conditions. Monitoring activities include continuous...

Truini, Margot; Baum, Bradley M.; Littin, Gregory R.; Shingoitewa-Honanie, Gayl
Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona: 1998; 2000; OFR; 2000-66; Truini, Margot; Baum, Bradley M.; Littin, Gregory R.; Shingoitewa-Honanie, Gayl

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Year Published: 2000

Hydrogeology of the regional aquifer near Flagstaff, Arizona, 1994-97

Sandstones, siltstones, and limestones that are Pennsylvanian to Permian in age underlie the southern part of the Colorado Plateau near Flagstaff, Arizona, and contain a complex regional aquifer that has become increasingly important as a source of water for domestic, municipal, and recreational uses. Ground-water flow in the regional aquifer is...

Bills, Donald J.; Truini, Margot; Flynn, Marilyn E.; Pierce, Herbert A.; Catchings, Rufus D.; Rymer, Michael J.
Hydrogeology of the regional aquifer near Flagstaff, Arizona, 1994-97; 2000; WRI; 2000-4122; Bills, Donald J.; Truini, Margot; Flynn, Marilyn E.; Pierce, Herbert A.; Catchings, Rufus D.; Rymer, Michael J.

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Year Published: 2000

Method to identify wells that yield water that will be replaced by water from the Colorado River downstream from Laguna Dam in Arizona and California

Accounting for the use of Colorado River water is required by the U.S. Supreme Court decree, 1964, Arizona v. California. Water pumped from wells on the flood plain and from certain wells on alluvial slopes outside the flood plain is presumed to be river water and is accounted for as Colorado River water. The accounting-surface method developed...

Owen-Joyce, Sandra J.; Wilson, Richard P.; Carpenter, Michael C.; Fink, James B.
Method to identify wells that yield water that will be replaced by water from the Colorado River downstream from Laguna Dam in Arizona and California; 2000; WRI; 2000-4085; Owen-Joyce, Sandra J.; Wilson, Richard P.; Carpenter, Michael C.; Fink, James B.

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Year Published: 2000

Chemical characteristics of urban stormwater sediments and implications for environmental management, Maricopa County, Arizona

Investigations of the chemical characteristics of urban stormwater sediments in the rapidly growing Phoenix metropolitan area of Maricopa County, Arizona, showed that the inorganic component of these sediments generally reflects geologic background values. Some concentrations of metals were above background values, especially cadmium, copper, lead...

Parker, J.T.C.; Fossum, K.D.; Ingersoll, T.L.
Chemical characteristics of urban stormwater sediments and implications for environmental management, Maricopa County, Arizona; 2000; Article; Journal; Environmental Management; Parker, J. T. C.; Fossum, K. D.; Ingersoll, T. L.

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Year Published: 1999

Monitoring the Effects of Ground-Water Withdrawals from the N Aquifer in the Black Mesa Area, Northeastern Arizona

Littin, Gregory R.
Monitoring the Effects of Ground-Water Withdrawals from the N Aquifer in the Black Mesa Area, Northeastern Arizona; 1999; FS; 064-99; Littin, Gregory R.

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Year Published: 1999

Ground-water quality in the Sierra Vista subbasin, Arizona, 1996-97

Coes, Alissa L.; Gellenbeck, Dorinda J.; Towne, Douglas Clark
Ground-water quality in the Sierra Vista subbasin, Arizona, 1996-97; 1999; WRI; 99-4056; Coes, Alissa L.; Gellenbeck, Dorinda J.; Towne, Douglas Clark

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Year Published: 1999

Hydrogeologic investigations of the Sierra Vista subwatershed of the Upper San Pedro Basin, Cochise County, southeast Arizona

The hydrogeologic system in the Sierra Vista subwatershed of the Upper San Pedro Basin in southeastern Arizona was investigated for the purpose of developing a better understanding of stream-aquifer interactions. The San Pedro River is an intermittent stream that supports a narrow corridor of riparian vegetation. Withdrawal of ground water will...

Pool, Donald R.; Coes, Alissa L.
Hydrogeologic investigations of the Sierra Vista subwatershed of the Upper San Pedro Basin, Cochise County, southeast Arizona; 1999; WRI; 99-4197; Pool, Donald R.; Coes, Alissa L.

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Year Published: 1999

Ground-water quality in alluvial basins that have minimal urban development, south-central Arizona

Ground-water quality data (1917-96) from 772 wells in 16 alluvial basins that have minimal urban development were used to determine the effect of nonurban factors on ground-water quality in south- central Arizona. Characterization of the spatial variability of ground-water quality within and among alluvial basins that have minimal urban...

Gellenbeck, Dorinda J.; Coes, Alissa L.
Ground-water quality in alluvial basins that have minimal urban development, south-central Arizona; 1999; WRI; 99-4005; Gellenbeck, Dorinda J.; Coes, Alissa L.

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Year Published: 1999

Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona, 1997

The Black Mesa monitoring program is designed to document long-term effects of ground-water from the N aquifer by industrial and municipal users. The N aquifer is the major source of water in the 5,400-square-mile Black Mesa area, and the ground water occurs under confined and unconfined conditions. Monitoring activities include continuous and...

Littin, Gregory R.; Baum, Bradley M.; Truini, Margot
Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona, 1997; 1999; OFR; 98-653; Littin, Gregory R.; Baum, Bradley M.; Truini, Margot

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Year Published: 1998

Modeling of flood-deposited sand distributions in a reach of the Colorado River below the Little Colorado River, Grand Canyon, Arizona

A release from Glen Canyon Dam during March-April 1996 was designed to test the effectiveness with which the riparian environment could be renewed with discharges greatly in excess of the normal powerplant-restricted maximum. Of primary concern was the rebuilding of sand deposits along the channel sides that are important to the flora and fauna...

Wiele, S.M.
Modeling of flood-deposited sand distributions in a reach of the Colorado River below the Little Colorado River, Grand Canyon, Arizona; 1998; WRI; 97-4168; Wiele, S. M.

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Year Published: 1997

Modeling of sand movement storage in the Colorado River through the Grand Canyon

Wiele, Stephen Mark
Modeling of sand movement storage in the Colorado River through the Grand Canyon; 1997; FS; 227-96; Wiele, Stephen Mark

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Year Published: 1997

Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona, 1996

The Black Mesa monitoring program is designed to document long-term effects of ground-water pumping from the N aquifer by industrial and municipal users. The N aquifer is the major source of water in the 5,400-square-mile Black Mesa area, and the ground water occurs under confined and unconfined conditions. Monitoring activities include...

Littin, Gregory R.; Monroe, Stephen A.
Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona, 1996; 1997; OFR; 97-566; Littin, Gregory R.; Monroe, Stephen A.

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June 30, 2018

Understanding Floods | Long-term Streamflow Data Collection

The USGS is developing methods to improve data collection during floods to gain new insight into the rise and fall of flood waters. In the past, the only data left behind after a flood was how high the water got, or the peak of the flood. This video presents the methodology that hydrologists are using to set up a Continuous Slope-area Reach in remote areas that are

May 11, 2018

Image of the Week - Rattlesnake Fire, AZ

Landsat and Sentinel sensors capture the Rattlesnake Fire as it burns in Arizona.

At the USGS EROS Center, we study land change, operate the Landsat satellites, and maintain the longest, continuously acquired collection of images of the Earth's land surface.

USGS EROS Center (https://eros.usgs.gov/)

May 8, 2018

Advances in Streamgaging | Reach-Scale Monitoring Experiment (2 of 2)

In this second installment of a two part series, The Arizona Water Science Center, in partnership with the USDA Agricultural Research Service, reviews the results of an experiment to verify remote methods that measure flood flows at the Walnut Gulch Experimental Watershed. What makes this experiment unique are the super-critical runoff flumes that precisely measure

Satellite image of the fire in Arizona.
May 1, 2018

Rattlesnake Fire, Arizona

The 2018 fire season is already active in the western United States. One of the larger wildfires so far is the Rattlesnake Fire. 

Sonoran desert scene showing invasion by red brome grass and fire scars on a saguaro cactus.
April 30, 2018

Red Brome Carries Fire and Burns Saguaros

Bromus Rubens (red brome) is an invasive annual grass that grows in warmer deserts of the Southwest U.S. It can carry fires in systems that aren't fire adapted, causing lasting damage to desert flora, as shown here in the Sonoran desert north of Phoenix, AZ. The

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Photo of sideview of a structure that blocks rainfall
April 18, 2018

Rainout shelters allow researchers to study the effects of drought

This rainout shelter blcoks about 35% of the natural rainfall, allowing researchers to understand the effects of drought on plants in the southwestern United States.

Photo of structure which blocks about 35% of rainfall
April 17, 2018

Rainout shelters allow researchers to study effects of drought

Rainout shelters block about 35% of natural rainfall, allowing researchers to study the effects of drought on plants in the arid and semiarid southwestern United States. 

photo of structure which blocks rainfall
April 17, 2018

Rainout structures allow researchers to study the effects of drought

This rainout structure blocks about 35% of the natural rainfall, allowing researchers to study the effects of drought on plants in the southwestern United States.

Two men stand in a grassland beneath a sky filled with fluffy cumulus clouds and a blue sky.
March 31, 2018

Standing in the field with managers

Touring public lands, guided by the people who manage the lands, is a important to RAMPS. On these tours we get to meet the passionate people, understand their challenges and aspirations, and help make steps towards innovative science-based solutions. In this photo staff from BLM's Aqua Fria National Monument stand with USGS scientist, Seth Munson and discuss how to

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View of the sonoran desert at Organ Pipe Cactus National Monument showing an organ pipe cactus and mountains of Mexico
February 28, 2018

Organ Pipe Cactus National Monument

Organ pipe cactus are rare in the Sonoran desert in the U.S. They can only be found in and around Organ Pipe Cactus National Monument, shown here. The distribution of Organ Pipe Cactus is limited due to lack of tolerance for cold temperatures. The biota of the Sonoran desert is particularly senstive to disturbance. Soils often erode quickly once vegetation is removed. The

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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

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View from Canyonlands Research Center
March 15, 2017

Arid and semiarid ecosystems are expected to experience significant changes in temperature and precipitation patterns, which may affect soil organisms in ways that cause surfaces to become lighter in color and thus reflect more sunlight, according to a new U.S. Geological Survey study.

Lake Mead
March 15, 2017

The Colorado River system provides about 35 million Americans with a portion of their water supply. It irrigates 5½ million acres of land in the West and provides water to tribes, parks, and wildlife. The system serves parts of seven States and Mexico—but reservoir levels have crept lower over the past several years, sparking questions about how much water remains and who will have access.

Photo of Pigeon Canyon just before it merges with Snake Gulch in northern Arizona. 
January 24, 2017

Uranium levels in Pigeon Spring, just north of the Grand Canyon, are likely due to a natural source of uranium and not related to the nearby former Pigeon Mine, according to a recent study by the U.S. Geological Survey.

Photo of a young girl drinking water, which likely originated from groundwater sources. 
January 19, 2017

A regional assessment of untreated groundwater in the Basin and Range basin-fill aquifers, which include parts of Nevada, California, Arizona, Utah and adjacent states, is now available from the U.S. Geological Survey.

Photo of scientists conducting water chemistry tests for the San Pedro River aquifer. 
December 20, 2016

For the first time, information about the San Pedro River Aquifer is now available from both the U.S. and Mexico in a new, collaborative report issued from the International Boundary and Water Commission, the Mexican National Water Commission, the U.S. Geological Survey and the Universities of Arizona and Sonora.

Laura Norman, USGS scientist, presenting
December 17, 2016

There was a full house at Cady Hall on Saturday, Dec. 17 to hear USGS scientist Laura Norman, PhD, talk about our water, the liquid gold of the Patagonia watershed. Her presentation was sponsored by the Friends of Sonoita Creek (FOS).

USGS
November 21, 2016

An article published in the Scientific American describes how conservationists along the poverty-stricken Arizona–Mexico are repairing habitat for more than 900 species of wild pollinators and boosting livelihoods.

Photo from Space Racers
October 26, 2016

Kids can visit the USGS Astrogeology Science Center before Nov. 6 for a chance to win an annual membership or a trip to U.S. Space & Rocket Center's Space Camp.

Satellite images showing the condition of vegetation after the 2014 Minute 319 pulse flow.
October 24, 2016

In 2014, a large pulse of water was released into the mostly dry delta of the Colorado River along the U.S.-Mexico border. U.S. Geological Survey scientists are studying the effects of the pulse on the environment as part of a historic, bi-national collaborative effort. The pulse flow and the need to study its effects were accepted as part of the Minute 319 of the 1944 U.S.-Mexico Water Treaty.

USGS
October 20, 2016

Scientists have discovered possible evidence for water-rich minerals on the surface of the largest metallic asteroid in the solar system, according to a study by the U.S. Geological Survey and NASA. 

Photo showing the Great Basin area
October 11, 2016

Large precipitation events that occur about every 10 years are a critical source of recharge for replenishing groundwater resources, according to a new study by the U.S. Geological Survey and the Bureau of Reclamation.

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