All Maps

The U.S. Geological Survey, in cooperation with the Puerto Rico Electric Power Authority, conducted a sedimentation survey of Lago Guayabal in 2017 to determine reservoir infill sedimentation rates, generate a bathymetric map of the bottom elevations of the reservoir, and create a stage-volume relation. The original (1913) capacity of Lago Guayabal was 11.82 million cubic meters, and...

The December 18, 2019, overflight provided updated aerial photographs of Kīlauea summit, covering the caldera floor and showing the current size of the water pond in Halema‘uma‘u crater.

The December 18 overflight provided updated thermal images of Kīlauea summit, covering the caldera floor and showing the warm surface of the water pond in Halema‘uma‘u crater.

The geologic map of the Blythe 7.5' quadrangle spans about 60 percent of the width of the Holocene floodplain and valley floor of the lower Colorado River and the adjacent lower piedmont on the east side of the Colorado River Valley. This map depicts a composite geologic record of the river’s response to the transition from a natural flow regime to a strictly regulated one created by a...

The Ouachita Mountains aquifer system potentiometric-surface map is one component of the Hot Springs Bypass Groundwater Monitoring Project. The potentiometric-surface map provides a baseline assessment of shallow groundwater levels and flow directions before the construction of the Arkansas Department of Transportation planned extension of the Highway 270 bypass, east of Hot Springs...

The area encompassed by the geologic map of the Ferncliff and Louisa, Va., 7.5-minute quadrangles includes the hypothetical surface projection of the Quail fault, which is the subsurface fault that was responsible for the 2011 magnitude 5.8 (M5.8) Mineral, Va., earthquake. The mapping shows that the Quail fault appears to have reactivated the Harris Creek fault, a Paleozoic fault that...