Publications
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Thermally induced fracture of macroscale surficial granite sheets
Geologically diverse landforms around the world show indications of energetic macroscale fracture. These fractures are sometimes displayed dramatically as so-called “A-tents”, whereby relatively thin rock sheets push upwards and fracture, forming tent-like voids beneath the ruptured sheets. The origin and formation of such features has been a topic of considerable interest and analysis for over a
Authors
Brian D. Collins, Greg M. Stock, Martha C. Eppes
Tools and methods in participatory modeling: Selecting the right tool for the job
Various tools and methods are used in participatory modelling, at different stages of the process and for different purposes. The diversity of tools and methods can create challenges for stakeholders and modelers when selecting the ones most appropriate for their projects. We offer a systematic overview, assessment, and categorization of methods to assist modelers and stakeholders with their choic
Authors
Alexey Voinov, Karen Jenni, Steven Gray, Nagesh Kolagani, Pierre D. Glynn, Pierre Bommel, Christina Prell, Moira Zellner, Michael Paolisso, Rebecca Jordan, Eleanor J. Sterling, Laura Schmitt Olabasi, Philippe J. Giabbanelli, Zhanli Sun, Christophe Le Page, Sondoss Elsawah, Todd K. BenDor, Klaus Hubacek, Bethany K. Laursen, Antonie J. Jetter, Laura Basco Carrera, Alison Singer, Laura G. Young, Jessica Brunacini, Alex Smajgl
Bedrock mapping and seismic hazard assessment at Gold Basin landslide, Washington
The Gold Basin landslide is located along the South Fork Stillaguamish River, within the Mount Baker-Snoqualmie National Forest in western Washington State. Recent concerns related to slope stability after the 2014 State Route 530 Landslide near Oso, Washington, forced the closure of the U.S. Forest Service Gold Basin Campground in May of 2014. In addition to safety concerns for National Forest vi
Authors
Lydia M. Staisch
Multi-Resource Analysis—Methodology and synthesis
This document introduces the Multi-Resource Analysis (MRA), a set of products that are being designed to integrate information on multiple natural resources in a region, combine that information with models of resource interrelationships and scenarios of change, and provide meaningful insights on the implications of those changes to people and the resources they value. The MRA builds from and enha
Authors
Karen E. Jenni, Emily J. Pindilli, Richard Bernknopf, Timothy L. Nieman, Carl Shapiro
Geology and geologic history: Overview of the geology of the San Francisco Bay region
The geology of San Francisco and the surrounding northern and central California area has played a pivotal role in the development of our understanding of Earth processes, especially the process of tectonic accretion at a continental margin and the development of transform plate margins. The Franciscan Complex, which underlies most (or perhaps all) of the City and County of San Francisco, is wide
Authors
Russell Graymer
Flushing of the deep Pacific Ocean and the deglacial rise of atmospheric CO2 concentrations
During the last deglaciation (19,000–9,000 years ago), atmospheric CO2increased by about 80 ppm. Understanding the mechanisms responsible for this change is a central theme of palaeoclimatology, relevant for predicting future CO2 transfers in a warming world. Deglacial CO2 rise hypothetically tapped an accumulated deep Pacific carbon reservoir, but the processes remain elusive as they are undercon
Authors
Jianghui Du, Brian Haley, Alan Mix, Maureen Walczak, Summer K. Praetorius
Global and Arctic climate sensitivity enhanced by changes in North Pacific heat flux
Arctic amplification is a consequence of surface albedo, cloud, and temperature feedbacks, as well as poleward oceanic and atmospheric heat transport. However, the relative impact of changes in sea surface temperature (SST) patterns and ocean heat flux sourced from different regions on Arctic temperatures are not well constrained. We modify ocean-to-atmosphere heat fluxes in the North Pacific and
Authors
Summer K. Praetorius, Maria A. Rugenstein, Geeta Persad, Ken Caldeira
Carving Grand Canyon’s inner gorge: A test of steady incision versus rapid knickzone migration
A recent study posits that much of the 240-m-deep inner gorge of Grand Canyon was carved between 500 and 400 ka via passage of a migrating knickzone with incision rates of ~1600 m/Ma during that time period; this was based on dating of a ca. 500 ka travertine deposit perched on the rim of the inner gorge, near Hermit Rapid, and a ca. 400 ka travertine drape that extends to within 60 m of river lev
Authors
Ryan S. Crow, Karl E. Karlstrom, Laura J. Crossey, Victor Polyak, Yemane Asmerom, William C. McIntosh
Geoelectric hazard maps for the Pacific Northwest
Maps of extreme value, horizontal component geoelectric field amplitude are constructed for the Pacific Northwest United States (and parts of neighboring Canada). Multidecade long geoelectric field time series are calculated by convolving Earth surface impedance tensors from 71 discrete magnetotelluric survey sites across the region with historical 1‐min (2‐min Nyquist) geomagnetic variation time
Authors
Jeffrey J. Love, Greg M. Lucas, Anna Kelbert, Paul A. Bedrosian
Outburst floods provide erodability estimates consistent with long-term landscape evolution
Most current models for the landscape evolution over geological timescales are based on semi-empirical laws that consider riverbed incision proportional to rock erodability (dependent on lithology) and to the work performed by water flow (stream power). However, the erodability values obtained from these models are entangled with poorly known conditions of past climate and streamflow. Here we use
Authors
Daniel Garcia-Castellanos, Jim E. O'Connor
A database of biodiversity and habitat quantification tools used in market-based conservation
Market-based conservation uses economic incentives to leverage market forces in ways that encourage and improve efficiency in the restoration, enhancement, and preservation of species and habitats. Biodiversity and habitat quantification tools are vital to the operation of this conservation strategy, as they are used to measure the quality and functionality of areas of land that have undergone or
Authors
Scott J. Chiavacci, Emily J. Pindilli
Breaching of strike-slip faults and successive flooding of pull-apart basins to form the Gulf of California seaway from ca. 8–6 Ma
The geologic record of the formation of marine basins during continental rifting is uncommonly preserved. Using GIS-based paleotectonic maps, we show that marine basin formation in the Gulf of California–Salton trough oblique rift (Mexico and the United States) occurred in a stepwise manner as crustal thinning lowered elevations within the Gulf of California Shear Zone, and subsidence along strike
Authors
Paul J. Umhoefer, Michael H. Darin, Scott E. K. Bennett, Lisa A. Skinner, Rebecca J. Dorsey, Michael E. Oskin