Physical Sciences and Mathematics | Open Access Articles

Mantle-Derived Helium In Hot Springs Of The Cordillera Blanca, Peru: Implications For Mantle-To-Crust Fluid Transfer In A Flat-Slab Subduction Setting, Dennis L. Newell, Micah J. Jessup, David R. Hilton, Colin Shaw, Cameron Hughes

Geosciences Faculty Publications

Fault-controlled hot springs in the Cordillera Blanca, Peru provide geochemical evidence of mantle-derived fluids in a modern flat-slab subduction setting. The Cordillera Blanca is an ~200km-long mountain range that contains the highest peaks in the Peruvian Andes, located in an amagmatic reach of the Andean arc. The Cordillera Blanca detachment defines the southwestern edge of the range and records a progression of top-down-to-the-west ductile shear to brittle normal faulting since ~5Ma. Hot springs, recording temperatures up to 78°C, issue along this fault zone and are CO₂-rich, near neutral, alkaline-chloride to alkaline-carbonate waters, with elevated trace metal contents including …

Go to article

Forecasting The Response Of Earth's Surface To Future Climatic And Land Use Changes: A Review Of Methods And Research Needs, Jon D. Pelletier, A. Brad Murray, Jennifer L. Pierce, Paul R. Bierman, David D. Breshears, Benjamin T. Crosby, Michael Ellis, Efi Foufoula-Georgiou, Arjun M. Heimsath, Chris Houser, Nick Lancaster, Marco Marani, Dorothy J. Merritts, Laura J. Moore, Joel Pederson, Michael J. Poulos, Tammy M. Rittenour, Joel C. Rowland, Peter Ruggiero, Dylan J. Ward, Andrew D. Wickert, Elowyn M. Yager

Geosciences Faculty Publications

In the future, Earth will be warmer, precipitation events will be more extreme, global mean sea level will rise, and many arid and semiarid regions will be drier. Human modifications of landscapes will also occur at an accelerated rate as developed areas increase in size and population density. We now have gridded global forecasts, being continually improved, of the climatic and land use changes (C&LUC) that are likely to occur in the coming decades. However, besides a few exceptions, consensus forecasts do not exist for how these C&LUC will likely impact Earth-surface processes and hazards. In some cases, we have …

Go to article

Active Salt Deformation And Rapid, Transient Incision Along The Colorado River Near Moab, Utah, Andrew P. Jochems, Joel L. Pederson

Geosciences Faculty Publications

In certain settings, erosion is driven by and balanced with tectonic uplift, but the evolution of many landscapes is dominated by other factors such as geologic substrate, drainage history, and transient incision. The Colorado Plateau is an example where these controls are debated and where salt deformation is hypothesized to be locally active and driven by differential unloading, although this is unconfirmed and unquantified in most places. We use luminescence-dated Colorado River terraces upstream of Moab, Utah, to quantify rates of salt-driven subsidence and uplift at the local scale. Active deformation in the study area is also supported by patterns …

Go to article

Pleistocene Relative Sea Levels In The Chesapeake Bay Region And Their Implications For The Next Century, Benjamin D. Dejong, Paul R. Bierman, Wayne L. Newell, Tammy M. Rittenour, Shannon A. Mahan, Greg Balco, Dylan H. Rood

Geosciences Faculty Publications

Today, relative sea-level rise (3.4 mm/yr) is faster in the Chesapeake Bay region than any other location on the Atlantic coast of North America, and twice the global average eustatic rate (1.7 mm/yr). Dated interglacial deposits suggest that relative sea levels in the Chesapeake Bay region deviate from global trends over a range of timescales. Glacio-isostatic adjustment of the land surface from loading and unloading of continental ice is likely responsible for these deviations, but our understanding of the scale and timeframe over which isostatic response operates in this region remains incomplete because dated sea-level proxies are mostly limited to …

Go to article

Physical Sciences and Mathematics Commons^™

Full-Text Articles in Physical Sciences and Mathematics

Mantle-Derived Helium In Hot Springs Of The Cordillera Blanca, Peru: Implications For Mantle-To-Crust Fluid Transfer In A Flat-Slab Subduction Setting, Dennis L. Newell, Micah J. Jessup, David R. Hilton, Colin Shaw, Cameron Hughes

Geosciences Faculty Publications

Geosciences Faculty Publications

Active Salt Deformation And Rapid, Transient Incision Along The Colorado River Near Moab, Utah, Andrew P. Jochems, Joel L. Pederson

Geosciences Faculty Publications

Pleistocene Relative Sea Levels In The Chesapeake Bay Region And Their Implications For The Next Century, Benjamin D. Dejong, Paul R. Bierman, Wayne L. Newell, Tammy M. Rittenour, Shannon A. Mahan, Greg Balco, Dylan H. Rood

Geosciences Faculty Publications