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Science and Products
Our research goals are to provide the scientific information, knowledge, and tools required to ensure that decisions about land and resource use, management practices, and future development in the coastal zone and adjacent watersheds can be evaluated with a complete understanding of the probable effects on coastal ecosystems and communities, and a full assessment of their vulnerability to...
Marine geohazards are sudden and extreme events beneath the ocean that threaten coastal populations. Such underwater hazards include earthquakes, volcanic eruptions, landslides, and tsunamis.
Devastating earthquakes in Japan (2011) and Chile (2010) that spawned pan-oceanic tsunamis sent a sobering reminder that U.S. coastlines are also vulnerable to natural disasters that originate in...
Faunal and stable isotopic analyses of benthic foraminifera from the Southeast Seep on Kimki Ridge offshore southern California, USA
We investigated the benthic foraminiferal faunal and stable carbon and oxygen isotopic composition of a 15-cm push core (NA075-092b) obtained on a Telepresence-Enabled cruise to the Southeast Seep on Kimki Ridge offshore southern California. The seep core was taken at a depth of 973 m in the vicinity of a Beggiatoa bacterial mat and vesicomyid...McGann, Mary; Conrad, James E.
Seafloor fluid seeps on Kimki Ridge, offshore southern California: Links to active strike-slip faulting
The Kimki Ridge fluid seeps are located in western Catalina Basin about 60 km southwest of the southern California mainland and at a water depth of approximately 1100 m. Multichannel seismic reflection profiles collected by the U.S. Geological Survey (USGS) in 2014 show acoustic transparency within the Kimki...Conrad, James E.; Prouty, Nancy G.; Walton, Maureen A. L.; Kluesner, Jared W.; Maier, Katherine L.; McGann, Mary; Brothers, Daniel; Roland, Emily C.; Dartnell, Peter
Developing Foram-AMBI for biomonitoring in the Mediterranean: Species assignments to ecological categories
Most environmental bio-monitoring methods using the species composition of marine faunas define the Ecological Quality Status of soft bottom ecosystems based on the relative proportions of species assigned to a limited number of ecological categories. In this study we analyse the distribution patterns of benthic foraminifera in the Mediterranean...Jorissen, Frans; Nardelli, Maria P.; Almogi-Labin, Ahuva; Barras, Christine; Bergamin, Luisa; Bicchi, Erica; El Kateb, Akram; Ferraro, Luciana; McGann, Mary; Morigi, Caterina; Romano, Elena; Sabattini, Anna; Schweizer, Magali; Spezzaferri, Silvia
Selective transport of palynomorphs in marine turbiditic deposits: An example from the Ascension-Monterey Canyon system offshore central California
The pollen assemblage of a deep-sea core (15G) collected at lower bathyal depths (3491 m) on a levee of Monterey Canyon off central California was investigated to gain insights into the delivery processes of terrigenous material to submarine fans and the effect this transport has on the palynological record. Thirty-two samples were obtained down...McGann, Mary
Unraveling the channel–lobe transition zone with high-resolution AUV bathymetry: Navy Fan, offshore Baja California, Mexico
Ultra-high-resolution (1 m * 1 m * 0.25 m) bathymetry was acquired with an autonomous underwater vehicle (AUV) over a sector of the Navy Fan offshore Baja California. The survey specifically targeted an area where the former interpretation of the fan showed a channel–lobe transition; however, the lobe and the transition were not recognized....Carvajal, Cristian; Paull, Charles K.; Caress, David W.; Fildani, Andrea; Lundsten, Eve M.; Anderson, Krystle; Maier, Katherine L.; McGann, Mary; Gwiazda, Roberto; Herguera, Juan Carlos
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...Maier, Katherine L.; Paull, Charles K.; Brothers, Daniel; Caress, David W.; McGann, Mary; Lundsten, Eve M.; Anderson, Krystle; Gwiazda, Roberto
Records of continental slope sediment flow morphodynamic responses to gradient and active faulting from integrated AUV and ROV data, offshore Palos Verdes, southern California Borderland
Variations in seabed gradient are widely acknowledged to influence deep-water deposition, but are often difficult to measure in sufficient detail from both modern and ancient examples. On the continental slope offshore Los Angeles, California, autonomous underwater vehicle, remotely operated vehicle, and shipboard methods were used to collect a...Maier, Katherine L.; Brothers, Daniel; Paull, Charles K.; McGann, Mary; Caress, David W.; Conrad, James E.
Use of mussel casts from archaeological sites as paleoecological indicators: An example from CA-MRN-254, Marin County, Alta California
Archaeological investigations at prehistoric site CA-MRN-254 at the Dominican University of California in Marin County, California, revealed evidence of Native American occupation spanning the past 1,800 years. A dominant source of food for the inhabitants in the San Francisco Bay area was the intertidal, quiet-water dwelling blue mussel (Mytilus...McGann, Mary; Starratt, Scott W.; Powell, Charles L.; Bieling, David G
Seafloor geomorphic manifestations of gas venting and shallow subbottom gas hydrate occurrences
High-resolution multibeam bathymetry data collected with an autonomous underwater vehicle (AUV) complemented by compressed high-intensity radar pulse (Chirp) profiles and remotely operated vehicle (ROV) observations and sediment sampling reveal a distinctive rough topography associated with seafloor gas venting and/or near-subsurface gas hydrate...Paull, C K; Caress, D W; Thomas, Hans; Lundsten, Eve M.; Anderson, Kayce; Gwiazda, Roberto; Riedel, M; McGann, Mary; Herguera, J C
The timing of sediment transport down Monterey Submarine Canyon, offshore California
While submarine canyons are the major conduits through which sediments are transported from the continents out into the deep sea, the time it takes for sediment to pass down through a submarine canyon system is poorly constrained. Here we report on the first study to couple optically stimulated luminescence (OSL) ages of quartz sand deposits and...Stevens, Thomas; Paull, Charles K.; Ussler, William III; McGann, Mary; Buylaert, Jan-Pieter; Lundsten, Eve M.
Geologic history of the summit of Axial Seamount, Juan de Fuca Ridge
Multibeam (1 m resolution) and side scan data collected from an autonomous underwater vehicle, and lava samples, radiocarbon-dated sediment cores, and observations of flow contacts collected by remotely operated vehicle were combined to reconstruct the geologic history and flow emplacement processes on Axial Seamount's summit and upper rift zones...Clague, David A.; Dreyer, Brian M; Paduan, Jennifer B.; Martin, Julie F; Chadwick, William W Jr; Caress, David W; Portner, Ryan A; Guilderson, Thomas P.; McGann, Mary; Thomas, Hans; Butterfield, David A; Embley, Robert W