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Publications produced by USGS scientists using core samples

Marine paleoseismic evidence for seismic and aseismic slip along the Hayward-Rodgers Creek fault system in northern San Pablo Bay

Distinguishing between seismic and aseismic fault slip in the geologic record is difficult, yet fundamental to estimating the seismic potential of faults and the likelihood of multi-fault ruptures. We integrated chirp sub-bottom imaging with targeted cross-fault coring and core analyses of sedimentary proxy data to characterize vertical deformation and slip behavior within an extensional fault ben
Janet Watt, Mary McGann, Renee K. Takesue, Thomas Lorenson

Late Holocene environmental change in Celestun Lagoon, Yucatan, Mexico

Epikarst estuary response to hydroclimate change remains poorly understood, despite the well-studied link between climate and karst groundwater aquifers. The influence of sea-level rise and coastal geomorphic change on these estuaries obscures climate signals, thus requiring careful development of paleoenvironmental histories to interpret the paleoclimate archives. We used foraminifera assemblages
Kyle Hardage, Joseph Street, Jorge A. Herrera-Silveira, Ferdinand Oberle, Adina Paytan

California deepwater investigations and groundtruthing (Cal DIG) I: Fault and shallow geohazard analysis offshore Morro Bay

The California Deepwater Investigations and Groundtruthing (Cal DIG) I project focuses on the potential seafloor hazards and impacts of alternative energy infrastructure in the outer continental shelf region offshore of south-central California. This is one of three reports covering a single study area located between Monterey and Point Conception, California in federal waters outside of the State

Maureen A. L. Walton, Charlie K Paull, Guy R. Cochrane, Jason A. Addison, Roberto Gwiazda, Daniel J. Kennedy, Eve M. Lundsten, Antoinette Gabrielle Papesh

Rebounds, regresses, and recovery: A 15-year study of the coral reef community at Pila‘a, Kaua‘i after decades of natural and anthropogenic stress events

Pila‘a reef on the north shore of Kaua‘i, Hawai‘i was subjected to a major flood event in 2001 that deposited extensive sediment on the reef flat, resulting in high coral mortality. To document potential recovery, this study replicated benthic and sediment surveys conducted immediately following the event and 15 years later. Coral cores were analyzed to determine coral growth rates and density. Ou
Ku'ulei S. Rodgers, A. Richards Dona, Y. O. Stender, A. O. Tsang, J. H. J. Han, Rebecca Weible, Nancy G. Prouty, Curt D. Storlazzi, Andrew M. Graham

Bomb-produced radiocarbon across the South Pacific Gyre — A new record from American Samoa with utility for fisheries science

Coral skeletal structures can provide a robust record of nuclear bomb produced 14C with valuable insight into air-sea exchange processes and water movement with applications to fisheries science. To expand these records in the South Pacific, a coral core from Tutuila Island, American Samoa was dated with density band counting covering a 59-yr period (1953–2012). Seasonal signals in elemental ratio
Allen Andrews, Nancy G. Prouty, Olivia Cheriton

Toward an integrative geological and geophysical view of Cascadia subduction zone earthquakes

The Cascadia subduction zone (CSZ) is an exceptional geologic environment for recording evidence of land level changes, tsunamis, and ground motion that reveals at least 19 great megathrust earthquakes over the past 10 kyr. Such earthquakes are among the most impactful natural hazards on Earth, transcend national boundaries, and can have global impact. Reducing the societal impacts of future event
Maureen A. L. Walton, Lydia M. Staisch, Tina Dura, Jessie K. Pearl, Brian L. Sherrod, Joan S. Gomberg, Simon E. Engelhart, Anne Trehu, Janet Watt, Jonathan P. Perkins, Robert C. Witter, Noel Bartlow, Chris Goldfinger, Harvey Kelsey, Ann Morey, Valerie J. Sahakian, Harold Tobin, Kelin Wang, Ray Wells, Erin Wirth

Plate boundary localization, slip-rates and rupture segmentation of the Queen Charlotte Fault based on submarine tectonic geomorphology

Linking fault behavior over many earthquake cycles to individual earthquake behavior is a primary goal in tectonic geomorphology, particularly across an entire plate boundary. Here, we examine the 1150-km-long, right-lateral Queen Charlotte-Fairweather fault system using comprehensive multibeam bathymetry data acquired along the Queen Charlotte Fault (QCF) offshore southeastern Alaska and western
Daniel Brothers, Nathaniel C. Miller, Vaughn Barrie, Peter J. Haeussler, H. Gary Greene, Brian D. Andrews, Olaf Zielke, Peter Dartnell

Sedimentary evidence of prehistoric distant-source tsunamis in the Hawaiian Islands

Over the past 200 years of written records, the Hawaiian Islands have experienced tens of tsunamis generated by earthquakes in the subduction zones of the Pacific "Ring of Fire" (e.g., Alaska-Aleutian, Kuril-Kamchatka, Chile, and Japan). Mapping and dating anomalous beds of sand and silt deposited by tsunamis in low-lying areas along Pacific coasts, even those distant from subduction zones, is cr
SeanPaul La Selle, Bruce M. Richmond, Bruce E. Jaffe, Alan Nelson, Frances Griswold, Maria E.M. Arcos, Catherine Chague, James M. Bishop, Piero Bellanova, Haunani H. Kane, Brent D. Lunghino, Guy R. Gelfenbaum

Coral skeleton δ15N as a tracer of historic nutrient loading to a coral reef in Maui, Hawaii

Excess nutrient loading to nearshore environments has been linked to declining water quality and ecosystem health. Macro-algal blooms, eutrophication, and reduction in coral cover have been observed in West Maui, Hawaii, and linked to nutrient inputs from coastal submarine groundwater seeps. Here, we present a forty-year record of nitrogen isotopes (δ15N) of intra-crystalline coral skeletal organi
Joseph Murray, Nancy G. Prouty, Sara E. Peek, Adina Paytan

Investigation of late Pleistocene and Holocene activity in the San Gregorio fault zone on the continental slope north of Monterey Canyon, offshore central California

We provide an extensive high‐resolution geophysical, sediment core, and radiocarbon dataset to address late Pleistocene and Holocene fault activity of the San Gregorio fault zone (SGFZ), offshore central California. The SGFZ occurs primarily offshore in the San Andreas fault system and has been accommodating dextral strike‐slip motion between the Pacific and North American plates since the mid‐Mio
Katherine L. Maier, Charles K. Paull, Daniel S. Brothers, David W. Caress, Mary McGann, Eve M. Lundsten, Krystle Anderson, Roberto Gwiazda