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Publications

Publications related to National Cooperative Geologic Mapping Program and its Components.

Filter Total Items: 167

Landslides triggered by Hurricane Maria: Assessment of an extreme event in Puerto Rico

Hurricane Maria hit the island of Puerto Rico on 20 September 2017 and triggered more than 40,000 landslides in at least three-fourths of Puerto Rico’s 78 municipalities. The number of landslides that occurred during this event was two orders of magnitude greater than those reported from previous hurricanes. Landslide source areas were commonly limited to surficial soils but also extended into und

Authors
Erin Bessette-Kirton, Corina Cerovski-Darriau, William Schulz, Jeffrey A. Coe, Jason W. Kean, Jonathan W. Godt, Matthew A. Thomas, K. Stephen Hughes

GSFLOW-GRASS v1.0.0: GIS-enabled hydrologic modeling of coupled groundwater–surface-water systems

The importance of water moving between the atmosphere and aquifers has led to efforts to develop and maintain coupled models of surface water and groundwater. However, developing inputs to these models is usually time-consuming and requires extensive knowledge of software engineering, often prohibiting their use by many researchers and water managers, thus reducing these models' potential to promo
Authors
G.-H. Crystal Ng, Andrew D. Wickert, Lauren D. Somers, Leila Saberi, Collin Cronkite-Ratcliff, Richard G. Niswonger, Jeffrey M. McKenzie

Establishing chronologies for alluvial-fan sequences with analysis of high-resolution topographic data: San Luis Valley, Colorado, USA

On active alluvial fans, debris-flow deposits and frequent avulsions produce a rough topographic surface. As is the case in many initially rough landforms produced by catastrophic processes, the topography of alluvial fans is progressively smoothed, producing textural differences useful in establishing relative age criteria for fans. Here, we outline an approach for defining a quantitative, numeri
Authors
Samuel Johnstone, Adam M. Hudson, Sylvia Nicovich, Chester A. Ruleman, Robert M. Sare, Ren A. Thompson

Hunting for landslides from Cascadia's great earthquakes

No abstract available.
Authors
Jonathan P. Perkins, Joshua J. Roering, William J. Burns, William Strubel, Bryan A. Black, Kevin Schmidt, Alison Duvall, Nancy C. Calhoun

Middle Pleistocene infill of Hinkley Valley by Mojave River sediment and associated lake sediment: Depositional architecture and deformation by strike-slip faults

Hinkley Valley in the Mojave Desert, near Barstow about 140 km northeast of Los Angeles and midway between Victorville Valley and the Lake Manix basin, contains a thick sedimentary sequence delivered by the Mojave River. Our study of sediment cores drilled in the valley indicates that Hinkley Valley was probably a closed playa basin with stream inflow from four directions prior to Mojave River inf
Authors
David M. Miller, Elizabeth Haddon, Victoria E. Langenheim, Andrew J. Cyr, Elmira Wan, Laura Walkup, Scott W. Starratt

Appalachian Basin stratigraphy, tectonics, and eustasy from the Blue Ridge to the Allegheny Front, Virginia and West Virginia

This guide is from a two-day field trip in western Virginia and eastern West Virginia held before the 2015 Geological Society of America annual meeting in Baltimore, Maryland. The field trip examines exposures of Paleozoic sedimentary strata in the Appalachian Basin starting in the Blue Ridge physiographic province, going through the Valley and Ridge physiographic province, and ending in the Appal
Authors
John T. Haynes, Alan D. Pitts, Daniel H. Doctor, Richard J. Diecchio, Mitchell B. Blake

Review of the geochemistry and metallogeny of approximately 1.4 Ga granitoid intrusions of the conterminous United States

The conterminous United States hosts numerous volumetrically significant and geographically dispersed granitoid intrusions that range in age from 1.50 to 1.32 billion years before present (Ga). Although previously referred to as A-type granites, most are better described as ferroan granites. These granitoid intrusions are distributed in the northern and central Rocky Mountains, the Southwest, the
Authors
Edward A. du Bray, Christopher S. Holm-Denoma, Karen Lund, Wayne R. Premo

The Colorado River and its deposits downstream from Grand Canyon in Arizona, California, and Nevada

Understanding the evolution of the Colorado River system has direct implications for (1) the processes and timing of continental-scale river system integration, (2) the formation of iconic landscapes like those in and around Grand Canyon, and (3) the availability of groundwater resources. Spatial patterns in the position and type of Colorado River deposits, only discernible through geologic mappin
Authors
Ryan S. Crow, Debra L. Block, Tracey J. Felger, Kyle House, Philip A. Pearthree, Brian F. Gootee, Ann M. Youberg, Keith A. Howard, L. Sue Beard

Vegetation response of a dry shrubland community to feral goat management on the island of Moloka‘i, Hawai‘i

The Hawaiian Islands are well known for their unique ecosystem assemblages that have a high proportion of endemic flora and fauna. However, since human colonization of this archipelago—starting with the arrival of Polynesian sailors approximately 1,200 years ago, and particularly following western contact in 1778—thousands of non-native species have been introduced to the Islands and many of these
Authors
James D. Jacobi, Jonathan D. Stock

Alaska geologic road guides

No abstract available.
Authors
Warren J. Nokleberg, Thomas K. Bundtzen, David B. Stone, Charles G. Mull

Isotopic characterization of late Neogene travertine deposits at Barrancas Blancas in the eastern Atacama Desert, Chile

Here we explore the potential of spring-related, surface and subsurface carbonates as an archive of paleoenvironmental change at Barrancas Blancas, located in the broadest and driest sector of the Atacama Desert at 24.5°S. From these deposits we present a new stable isotopic record of paleoenvironmental conditions over portions of the past ~ 11.5 Ma. U-Pb dates from the carbonates, both surface an
Authors
J. Quade, E.T. Rasbury, K.W. Huntington, Adam M. Hudson, H. Vonhof, K. Anchukaitis, Julio L. Betancourt, C. Latorre, M. Pepper

A 130,000-year-old archaeological site in southern California, USA

The earliest dispersal of humans into North America is a contentious subject, and proposed early sites are required to meet the following criteria for acceptance: (1) archaeological evidence is found in a clearly defined and undisturbed geologic context; (2) age is determined by reliable radiometric dating; (3) multiple lines of evidence from interdisciplinary studies provide consistent results; a
Authors
Steven R. Holen, Thomas A. Deméré, Daniel C. Fisher, Richard Fullagar, James B. Paces, George T. Jefferson, Jared M. Beeton, Richard A. Cerutti, Adam N. Rountrey, Lawrence Vescera, Kathleen A. Holen