Reports

No abstract available.

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean conventional resources of 10.4 billion barrels of oil and 53.3 trillion cubic feet of gas in the Santos Basin, Campos Basin, and Espírito Santo Basin provinces of Brazil.

Gambel’s quail (Callipepla gambelii) is the most widespread, abundant, and heavily harvested species of game quail in Arizona. Gambel’s quail population dynamics in Arizona are strongly influenced by seasonal weather conditions. This is particularly relevant for Gambel’s quail management as drought conditions are expected to increase in Arizona, and this may exacerbate inter-annual...

Pacific herring (Clupea pallasii) were collected from three sites in Prince William Sound (PWS), Alaska (Table 1) during the spring pre-spawn period from March 29 – April 1, 2024, to test for viral hemorrhagic septicemia virus (VHSV), viral erythrocytic necrosis (VEN), and Ichthyophonus prevalence (Table 1). Ichthyophonus was detected in 33% (59/180) of heart cultures from all sites...

No abstract available.

Understanding how climate change and variability will impact grassland ecosystems is crucial for successful grasslands management in the future. In 2020, the North Central Climate Adaptation Science Center began a project to establish a baseline of information to best serve grassland managers (that is, those individuals who develop grassland management plans, implement those plans on the...

Introduction At the Bascom Laser Diffraction Sedimentology Laboratory, which is located in the Florence Bascom Geoscience Center at U.S. Geological Survey (USGS) headquarters in Reston, Virginia, scientists use physical sedimentology and particle characterization techniques to conduct detailed sediment characterization. Scientists address research problems in collaboration with other...

Introduction Each mineral commodity chapter of the 2026 edition of the U.S. Geological Survey (USGS) Mineral Commodity Summaries (MCS) includes information on events, trends, and issues for each mineral commodity as well as discussions and tabular presentations on domestic industry structure, Government programs, tariffs, 5-year salient statistics, and world production, reserves, and...

Riparian ecosystems play a critical role in supporting wildlife habitats, maintaining water quality, and sustaining ecological resilience in arid landscapes. In the Upper Gila River level-4 Hydrologic Unit Code (HUC-4; Identification Number – 1504) watershed of Arizona and New Mexico, and across areas of the San Carlos Apache Tribe of the San Carlos Apache Reservation (hereafter, Tribe...

In 2024, the U.S. Geological Survey, in cooperation with the Tennessee Department of Transportation, updated the methods for predicting the magnitude and frequency of floods at ungaged locations on streams in urban areas in Tennessee. The study area included 136 streamgages in urban areas in Tennessee, Mississippi, Alabama, Georgia, South Carolina, and North Carolina that had at least 10...

Digital flood-inundation maps for a 2.7-mile reach of Río Grande De Loíza in Caguas, Puerto Rico, were created by the U.S. Geological Survey. Water-surface profiles were computed for the stream reach by using a one-dimensional, steady-state, step-backwater model. The model was calibrated to the current (2025) stage-streamflow relation (rating curve) for the U.S. Geological Survey...

The U.S. Geological Survey, in cooperation with the City of Brownsville, Texas, configured and calibrated a set of hydrologic models for a 217-square-mile study area in Cameron County in south Texas during 2022–23. The models were used for estimating runoff and quantities of water diverted from the Rio Grande/Rio Bravo del Norte (hereinafter referred to as the “Rio Grande”) to maintain...