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USGS2025

USGS Environmental Health Program—Per- and polyfluoroalkyl substances (PFAS) science activities [postcard]

Introduction The U.S. Geological Survey (USGS) Environmental Health Program conducts various activities related to PFAS (per- and polyfluoroalkyl substances) to understand their impacts on human health and the environment. Through these activities, the program aims to provide critical information and resources to address the challenges posed by PFAS contamination.

General Information Product↗
USGS1991

Geologic maps of science study area 3, Olympus Rupes, Mars

This map is one in a series of 1:500,000 -scale geologic maps initiated by the National Aeronautics and Space Administration to investigate areas of particular scientific interest on Mars. Olympus Mons is the largest known volcanic construct in the Solar System; it is more than 600 km across and more than 27 km above datum (fig, 1, sheet 1). The volcano and the great scarp that bounds it have been the subject of much scientific controversy. Although i t has been possible to generate an empirical model that closely resembles Olympus Mons (fig. 2, sheet 1), the dynamics of scarp formation are still unproven . The scarp area is thus a logical selection as a scientific study area. It has also been designated as a candidate site for a proposed lander/rover/sample-return mission to Mars (fig. 1, sheet 2) not only because the site may provide information about the origins of the scarp and the evolution of Olympus Mons, but also because the rocks of widely diverse ages may be studied from the samples collected from talus at the base of the scarp.

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USGS1991

Geologic map of science study area 1B, west Mangala Valles region of Mars

This map is one in a series of 1:500,000-scale geologic maps initiated by the National Aeronautic and Space Administration to investigate areas of particular scientific interest on Mars. The west Mangala Valles area merits detailed geologic study because it contains several small channels whose ages can be determined relative to geologic units that range in age from early (Noachian) to late (Amazonian) periods of Martian history. Because the small channels are of three ages and channels of each age are of a geomorphic type unique to that age, their study increases our understanding of the continuity of fluvial process on the evolutionary history of Mars. For these reasons, part of the area is a proposed-site for a sample-return mission to Mars.

IMAP↗
USGS1991

Geologic map of science study area 2, north Kasei Valles, Mars (MTM 25072 Quadrangle)

This map is one in a series of 1:500,000-scale geologic maps initiated by the National Aeronautics and Space Administration to investigate areas of particular scientific interest on Mars. The north Kasei Valles area (fig. 1) merits detailed geologic study because it c ontains part of a large channel system whose age can be determined relative to geologic units that range in age from early intermediate (Early Hesperian) to the very late (Late Amazonian) periods of Martian history . Also, many geomorphic features in the map area suggest changes in water level and multiple erosional events associated with the Kasei Valles system. Later erosional events are indicative of spring sapping ; small-scale, ground-water runoff; and water-mobilized debris flow. Therefore, this large-scale mapping has increased our understanding of the history of hydrolo gic processes on Mars (Chapman and Scott, 1989). For these reasons, part of the area is a candidate site for a sample-return mission to the planet.

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USGS1993

Geologic map of science study area 8, Apollinaris Patera region of Mars

Volcanoes are among the most imposing and geologically interesting features on Mars. Nearly 60 percent of the planet’s surface is covered by volcanic rocks dating from the Early Noachian to Late Amazonian Epochs (Tanaka and others, 1988). This map of the volcano Apollinaris Patera and surrounding area is one of a series of large-scale (1:500,000) geologic maps initiated by the National Aeronautics and Space Administration to investigate areas of particular scientific interest. The areas selected for mapping contain candidate landing sites for future sample-return missions to Mars (fig. 1). The map area is considered to be of special scientific interest for several reason: (1) it includes the prominent volcano Apollinaris Patera, a type of volcanic edifice unusual on Mars in that it is not associated with significant faulting and is partly surrounded by a basal scarp similar to that of its much larger counterpart at the base of Olympus Mons; (2) it is located in a major transition zone between ancient highlands to the south and much of the younger lowland plains to the north; (3) rocks have different origins and a ide range of ages occurring in the area; and (4) erosional processes associated with fluvial, volcanic, and eolian activity have shaped the terrain. The map area’s potential as a landing site is increased by its extensive, relatively smooth areas at low elevation (0 to 1 km), which would permit access by an automated vehicle and atmospheric breaking by a landing craft.

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USGS2001

Tampa Bay Integrated Science Pilot Study: wetland characterization

Coastal wetlands in Tampa Bay consist of mangrove forest and tidal salt marsh. Wetlands buffer storm surges, provide fish and wildlife habitat, and enhance water quality through the removal of water-borne nutrients and contaminants. Substantial areas of both mangrove and salt marsh have been lost to agricultural, residential and industrial development in this urban estuary. Wetlands restoration has been initiated in Tampa Bay. Baseline studies on the current condition of wetlands and historical and prehistorical information is needed for successful restoration planning and evaluation. A major objective of this component of the Tampa Bay pilot program was to characterize wetlands in Tampa Bay beginning with areas that differ in their degree of human-induced disturbance ( Fig. 1 ). The Alafia River area is urbanized, industrialized and dredged, whereas the Terra Ceia area has a history of agricultural use with associated soil berms and mosquito ditches, but has not been farmed for at least 20 years ( Fig. 2 ).

Open-File Report↗
USGS2001

Tampa Bay Integrated Science Pilot Study: Baseline mapping, land surface dynamics and predictive modeling, and hazards vulnerability studies

Tampa Bay and its environs have experienced phenomenal urban growth and significant changes in land cover and land-use practices over the past 50 years. This trend is expected to continue, with the impact of human activity broadening geographically and intensifying throughout the region. One of the immediate impacts of urban growth is the creation of additional impervious surfaces, which in turn, generate increased urban runoff that contributes to higher levels of nutrient loading in water bodies throughout the area. To better understand these and other anthropogenic affects on the ecology of the natural environment of the region, this component of the Tampa Bay Pilot Study took a broad basin-wide view. This regional view was intended to provide geographic and temporal context for the smaller intensely studied sample field site locations within the estuarine environment.

Open-File Report↗