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A novel non-destructive workflow for examining germanium and co-substituents in ZnS

A suite of complementary techniques was used to examine germanium (Ge), a byproduct critical element, and co-substituent trace elements in ZnS and mine wastes from four mineral districts where germanium is, or has been, produced within the United States. This contribution establishes a comprehensive workflow for characterizing Ge and other trace elements, which captures the full heterogeneity of s

The EDMAP Program: Training the next generation of geologic mappers

Introduction Detailed geologic maps are the basis of most earth science investigations and can be used for natural hazard mitigation, resource identification and exploration, infrastructure planning, and more. As a part of the U.S. Geological Survey (USGS) congressionally mandated National Cooperative Geologic Mapping Program (NCGMP), the EDMAP program (referred to as EDMAP) is a partnership betwe

A channel sampling strategy for measurement of mineral modal and chemical composition of drill cores: Application to lower oceanic crustal rocks from IODP Expedition 345 to the Hess Deep rift

We report a new sampling strategy for collecting representative samples of drill core. By splitting the core with a diamond saw into working and archive halves, the saw cuttings constitute a “channel” sample, the best subsample from which to obtain an average mineralogical and geochemical composition of a core. We apply this procedure to sampling core of the lower oceanic crust in the Hess Deep ob

A 1.8 million year history of Amazon vegetation

During the Pleistocene, long-term trends in global climate were controlled by orbital cycles leading to high amplitude glacial-interglacial variability. The history of Amazonian vegetation during this period is largely unknown since no continuous record from the lowland basin extends significantly beyond the last glacial stage. Here we present a paleoenvironmental record spanning the last 1800 kyr

A multiscale approach for monitoring groundwater discharge to headwater streams by the U.S. Geological Survey Next Generation Water Observing System Program—An example from the Neversink Reservoir watershed, New York

Groundwater-stream connectivity across mountain watersheds is critical for supporting streamflow during dry times and keeping streams cool during warm times, yet U.S. Geological Survey (USGS) stream measurements are often sparse in headwaters. Starting in 2019, the USGS Next Generation Water Observing System Program developed a multiscale methods and technology testbed approach to monitoring groun

Permafrost and climate change: Carbon cycle feedbacks from the warming Arctic

Rapid Arctic environmental change affects the entire Earth system as thawing permafrost ecosystems release greenhouse gases to the atmosphere. Understanding how much permafrost carbon will be released, over what time frame, and what the relative emissions of carbon dioxide and methane will be is key for understanding the impact on global climate. In addition, the response of vegetation in a warmin

Lateral moraines, ice-dammed lakes, and meltwater-carved channels in the Pelham, Shutesbury, Leverett area of west-central Massachusetts: A record of Connecticut Valley ice lobe retreat

Temporary ice-dammed glacial lakes formed high in the landscape in several westward sloping valleys on the east side of the Connecticut Valley lowland during late Wisconsinan deglaciation. These lakes were impounded by a lengthy lobe of ice that extended farther south in the lowland than at upland retreatal ice-margin positions (fig. 1). The formation, lowering, and drainage of these ice-dammed la

Biostratigraphically significant palynofloras from the Paleocene–Eocene boundary of the USA

Pollen and spores were recovered from the Paleocene Fort Union Formation and Paleocene–Eocene Willwood Formation of the Bighorn Basin (BHB), northwestern Wyoming, USA. In many local stratigraphic sections in the BHB, the base of the Eocene has been identified by the characteristic negative carbon isotope excursion (CIE) that marks the beginning of the Paleocene–Eocene Thermal Maximum (PETM). The p

Astrochronology of the Paleocene-Eocene Thermal Maximum on the Atlantic Coastal Plain

The chronology of the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma) remains disputed, hampering complete understanding of the possible trigger mechanisms of this event. Here we present an astrochronology for the PETM carbon isotope excursion from Howards Tract, Maryland a paleoshelf environment, on the mid-Atlantic Coastal Plain. Statistical evaluation of variations in calcium content and magnet

Using paleoecological data to inform decision making: A deep-time perspective

Latest climate models project conditions for the end of this century that are generally outside of the human experience. These future conditions affect the resilience and sustainability of ecosystems, alter biogeographic zones, and impact biodiversity. Deep-time records of paleoclimate provide insight into the climate system over millions of years and provide examples of conditions very different

Germanium redistribution during weathering of Zn mine wastes: Implications for environmental mobility and recovery of a critical mineral

Germanium (Ge) is a metal used in emerging energy technologies, communications, and defense, and has been deemed critical by the United States due to its essential applications and scarce supply. Germanium is recovered as a byproduct of zinc (Zn) sulfides, and mining and processing of these materials lead to waste that could act both as a source of extractable Ge and a source for exposure to human

Using mollusks as indicators of restoration in nearshore zones of south Florida's estuaries

Current south Florida ecosystem restoration efforts are focused on restoring more natural freshwater flow through the wetlands and into the estuaries to reestablish natural salinity gradients, particularly in the nearshore zones. Indicator taxa are used to monitor and assess restoration progress and the current suite of biota used for the estuaries in south Florida (Biscayne Bay, Florida Bay, and