About
346
Publications
58,916
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
15,162
Citations
Publications
Publications (346)
To date, only a few microbial community studies of cold seeps at the South China Sea (SCS) have been reported. The cold seep dominated by tubeworms was discovered at South Yungan East Ridge (SYER) offshore southwestern Taiwan by miniROV. The tubeworms were identified and proposed as Paraescarpia formosa sp. nov. through morphological and phylogenet...
Here we show how ultra‐high resolution seabed mapping using new technology can help to understand processes that sculpt submarine canyons. Time‐lapse seafloor surveys were conducted in the axis of Monterey Canyon, ∼50 km from the canyon head (∼1,840 m water depth) over an 18‐month period. These surveys comprised 5‐cm resolution multibeam bathymetry...
A high-resolution multibeam survey from a portion of the San Simeon Channel (offshore Morro Bay, California) captured a zone of recurring troughs and ridges adjacent to prominent submarine meander bends. Through an integrated study using surveying data, sediment core analysis, radiocarbon dating, and stable isotope measurements, we hypothesize that...
The Monterey Bay Aquarium Research Institute has been developing Autonomous Underwater Vehicles since 2000. Two sizes currently exist: Dorado class AUVs and Long Range AUVs. This document focuses on recent scientific discoveries made with the Dorado AUVs, which have operated in Monterey Bay, Southern California, the Juan de Fuca plate region offsho...
The shallow migration path of mudflow of the mud volcano MV420 on the continental slope of the Canadian Beaufort Sea is investigated in terms of thermal and geotechnical characteristics. MV420 is a nearly flat topped active mud volcano that emits methane and fluidized mud. Its top is at a depth of water of 420 m, within the gas hydrate stability zo...
캐나다 보퍼트해 대륙사면에 위치한 진흙화산420에서 한국-미국-캐나다 연구진이 쇄빙연구선 아라온을 이용한 종합해양탐사를 2022년 8~9월에 수행하였다. 2013, 2015, 2017, 그리고 2022년에 걸쳐 원격조정잠수정, 자동수중잠수정의 반복적인 탐사를 통해 진흙화산420의 지형변화가 모니터링 되고 있다. 다중음향측심 자료와 후방산란강도 자료를 이용하여 2016년과 2017년 사이에 진흙 분출이 이루어진 곳을 선정하여, 2017년에 이어 2022년에도 해양지열탐침을 이용한 과침투 실험을 수행하였다. 일반적인 해저면에 비해 상당히 부드러워, 해양지열탐침이 해저면 밑으로 깊이 파고드는 과침투가 일어났다. 과침투가 발생...
A partial skeleton of a blue or fin whale, estimated to have been 16.5 m in length and thought to have been lying on the seafloor for less than 10 years, was observed at a depth of 1288 m off western Vancouver Island, British Columbia, Canada (48.68 N, 126.84 W). Four push cores were taken at the site, three (15-26 cm in length) directly under caud...
Here we describe the methods and results for biological characterization of the benthos on a previously unexplored area of central California, USA seafloor. We conducted 40 remotely operated vehicle dives from 371–1173 m water depth. Seafloor habitats and megafauna (fish and invertebrates) were documented from 46.8 km of seafloor video footage. Our...
Barkley Canyon is one of the few known sites worldwide with the occurrence of thermogenic gas seepage and formation of structure-II and structure-H gas hydrate mounds on the seafloor. This site is the location of continuous seafloor monitoring as part of the Ocean Networks Canada (ONC) cabled observatory off the west coast off Vancouver Island, Bri...
Coastal and Marine Ecological Classification Standard (CMECS) geoform, substrate, and biotic component geographic information system (GIS) products were developed for the U.S. Exclusive Economic Zone (U.S. EEZ) of south- central California in the region of Santa Lucia Bank motivated by interest in development of offshore wind-energy capacity and in...
Significance
Temperature increases in Arctic regions have focused attention on permafrost degradation on land, whereas little is known about the dynamics of extensive glacial-age permafrost bodies now submerged under the vast Arctic Continental shelves. Repeated high-resolution bathymetric surveys show that extraordinarily rapid morphologic changes...
The near‐bed section of submarine gravity flows travels at the highest and most destructive speeds making direct measurements of this region of the flow difficult. Here results are presented from “boulder‐like” Benthic Event Detectors (BEDs) that measured their own rotation, depth and temperature while carried within the near‐bed region of gravity...
Mesozoic submarine carbonate escarpments are erosional features that host box canyons, the formation of which had been attributed to seepage erosion in view of their similarity to subaerial box canyons. The latter had been cited as diagnostic of groundwater activity, although the efficacy of fluid seepage as an erosive agent in bedrock remains cont...
https://cmgds.marine.usgs.gov/data-releases/datarelease/10.5066-P9E2OP35/
Water column data collected from moorings in Monterey Canyon, offshore California
These water column data files were collected in Monterey Canyon as part of the Monterey Canyon Coordinated Canyon Experiment (CCE). The CCE was set up to measure the passage of sediment gravity flows down Monterey Canyon. A dense array of sensors (more than 50) were d...
During the ARA08C expedition in 2017, sediment push cores were collected at an active mud volcano (420 m water depth) in the Canadian Beaufort Sea from two visually discriminative siboglinid tubeworm (ST) habitats that were colonized densely and less densely (ST1 and ST2, respectively). In this study, we investigated the biogeochemical and microbia...
Turbidity currents dominate sediment transfer into the deep ocean, and can damage critical seabed infrastructure. It is commonly inferred that powerful turbidity currents are triggered by major external events, such as storms, river floods, or earthquakes. However, basic models for turbidity current triggering remain poorly tested, with few studies...
Climate change in the Arctic has recently become a major scientific issue, and detailed information on the degradation of subsea permafrost on continental shelves in the Arctic is critical for understanding the major cause and effects of global warming, especially the release of greenhouse gases. The subsea permafrost at shallow depths beneath the...
Exploration of the continental slope of the Canadian Beaufort Sea has revealed a remarkable coalescence of slide scars with headwalls between 130 and 1100 m water depth (mwd). With increased depth, the scars widen and merge into one gigantic regional slide scar that is more than 100 km wide below ~1100 mwd. To understand the development of these fe...
Submarine canyons are deep, large-scale incisions that occur on the continental shelf and slope of all ocean margins. These landforms serve as preferential particle-transport conduits that connect the coastal zone with the deep-sea. Canyons have been studied for decades and are among the most iconic submarine geomorphic features. Advances in marine...
High-resolution bathymetry collected with an autonomous underwater vehicle (AUV) along the flanks of three ridges of the accretionary prism offshore southwestern (SW) Taiwan revealed more than 650 elongated depressions in water depths ranging from 1155 to 1420 m. The depressions are between 12 and 129 m long, 5 to 70 m wide, and up 9 m deep at thei...
Research on the depositional record of submarine fans and related turbidite systems has highlighted the importance of channel, lobe, and levee-overbank architectural elements as fundamental building blocks. However, many of the characteristics and processes of deposits left by flows traversing those fans remain elusive, as flows seem to be able to...
New high-resolution datasets across La Jolla submarine fan, offshore California, illuminate low-relief, down-dip widening conduits emanating from a deep-sea channel that deposited a combination of laterally extensive sand strata seemingly crisscrossed by distributary patterns. Extensive coverage of this sector of the seafloor shows submarine-fan ar...
Submarine turbidity currents are one of the most important sediment transfer processes on earth. Yet the fundamental nature of turbidity currents is still debated; especially whether they are entirely dilute and turbulent, or a thin and dense basal layer drives the flow. This major knowledge gap is mainly due to a near-complete lack of direct measu...
Turbidity currents transport globally significant volumes of sediment and organic carbon into the deep-sea and pose a hazard to critical infrastructure. Despite advances in technology, their powerful nature often damages expensive instruments placed in their path. These challenges mean that turbidity currents have only been measured in a few locati...
Seabed sediment flows called turbidity currents form some of the largest sediment accumulations, deepest canyons and longest channel systems on Earth. Only rivers transport comparable sediment volumes over such large areas; but there are far fewer measurements from turbidity currents, ensuring they are much more poorly understood. Turbidity current...
Transform faults have anomalously low rates of seismicity, but it’s not clear whether this reflects persistent earthquake-generating fault patches surrounded by creep, or the presence of creep and earthquakes at different times along the same patch. We use new, autonomous underwater vehicle high-resolution seafloor mapping to image the morphology o...
Turbidity currents transport globally significant volumes of sediment and organic carbon into the deep-sea and pose a hazard to critical infrastructure. Despite advances in technology, their powerful nature often damages expensive instruments placed in their path. These challenges mean that turbidity currents have only been measured in a few locati...
Research on the depositional record of submarine fans and related turbidite systems has highlighted the importance of channel, lobe and levee–overbank architectural elements as fundamental building blocks. However, many of the characteristics and processes of deposits left by flows traversing those fans remain elusive, because flows seem to be able...
Several mud volcanoes are active in the Canadian Beaufort Sea. In this study, we investigated vertical variations in methanotrophic communities in sediments of the mud volcano MV420 (420 m water depth) by analyzing geochemical properties, microbial lipids, and nucleic acid signatures. Three push cores were collected with a remotely operated vehicle...
Siboglinid tubeworms of the genus Oligobrachia that thrive in obligatory association with endosymbionts have been predominantly observed in Arctic and high-latitude Atlantic cold seeps. Metabolic features of endosymbionts provide fundamental understanding for the survival strategy of tubeworms in cold seeps. However, no information on the bacterial...
Globally, anthropogenic perturbations to sediment dispersal systems produce detrital signals that are evident in the recent sedimentary record. We review the study of anthropogenic perturbations to sediment dispersal systems from the perspective of detrital signals and discuss the use of provenance analysis in Anthropocene sedimentology. Anthropoce...
Submarine canyons are globally important conduits for sediment and organic carbon transport into the deep sea. Using a novel dataset from Monterey Canyon, offshore central California, that includes an extensive array of water column sampling devices, we address how fine-grained sediment and organic carbon are transported, mixed, fractionated, and b...
High-resolution mapping with an autonomous underwater vehicle (AUV) of a section of the San Clemente fault, offshore Southern California, reveals the largest documented cold-seep-associated barite deposits discovered to date. Although barite deposits along this fault, north of the mapped area, have been observed and sampled before in submersible di...
Submarine canyons are conduits for episodic and powerful sediment density flows (commonly called turbidity currents) that move globally significant amounts of terrestrial sediment and organic carbon into the deep sea, forming some of the largest sedimentary deposits on Earth. The only record available for most turbidity currents is the deposit they...
Multibeam bathymetric mapping of the Santa Monica Basin in the eastern Pacific has revealed the existence of a number of elevated bathymetric features, or mounds, harboring cold seep communities. During 2013–2014, mounds at ∼600 m water depth were observed for the first time and sampled by Monterey Bay Aquarium Research Institute’s ROV Doc Ricketts...
Carbonate escarpments are submarine limestone and dolomite cliffs that have been documented in numerous sites around the world. Their geomorphic evolution is poorly understood due to difficulties in assessing escarpment outcrops and the limited resolution achieved by geophysical techniques across their steep topographies. The geomorphic evolution o...
10 11 Seafloor sediment flows (turbidity currents) are among the volumetrically most 12 important yet least documented sediment transport processes on Earth. A scarcity 13 of direct observations means that basic characteristics, such as whether flows are 14 entirely dilute or driven by a dense basal layer, remain equivocal. Here we present 15 the m...
Long-term warming of the continental shelf of the Canadian Beaufort Sea caused by the transgression associated with the last deglaciation may be causing decomposition of relict offshore subsea permafrost and gas hydrates. To evaluate this possibility, pore waters from 118 sediment cores up to 7.3-m long were taken on the shelf and slope and analyze...
Submarine canyons are deep incisions observed along most of the world’s continental margins. Their topographic relief is as dramatic as that of any canyon or river valley on land but is hidden beneath the surface of the ocean. Our knowledge of canyons has therefore come primarily from remote sensing and sampling, and has involved contributions from...
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 strikeslip motion between the Pa...
Cyclic steps are long-wave (the ratio of wavelength to height is >>1), upstream-migrating, upper-flow-regime bedforms bounded by internal hydraulic jumps (i.e., transition from densimetric Froude supercritical to subcritical flow) in turbidity currents. They commonly occur in regions with high gradients and slope breaks. Here we review the morphody...
Submarine turbidity currents create some of the largest sediment accumulations on Earth, yet there are few direct measurements of these flows. Instead, most of our understanding of turbidity currents results from analyzing their deposits in the sedimentary record. However, the lack of direct flow measurements means that there is considerable debate...
Submarine landslides occurring along the margins of the Gulf of Mexico (GOM) represent a low-likelihood, but potentially damaging source of tsunamis. New multibeam bathymetry coverage reveals that mass wasting is pervasive along the Yucatán Shelf edge with several large composite landslides possibly removing as much as 70 km3 of the Cenozoic sedime...
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 den...
A suite of complementary survey tools aimed at producing 1-cm resolution bathymetric models co-registered with 2-mm pixel color photography has been assembled. The design goal is to produce quantitative documentation of both geological and biological features that will allow change over time to be assessed at vertical and lateral scales approaching...
Submarine landslides occurring along the margins of the Gulf of Mexico (GOM) represent a low-likelihood, but potentially damaging source of tsunamis. New multibeam bathymetry coverage reveals that mass wasting is pervasive along the Yucatán Shelf edge with several large composite landslides possibly removing as much as 70 km3 of the Cenozoic sedime...
Methane is a potent greenhouse gas, and there are concerns that its natural emissions from the Arctic could act as a substantial positive feedback to anthropogenic global warming. Determining the sources of methane emissions and the biogeochemical processes controlling them is important for understanding present and future Arctic contributions to a...
Methane is a potent greenhouse gas, and there are concerns that its natural emissions from the Arctic could
act as a substantial pos. feedback to anthropogenic global warming. Detg. the sources of methane and the
biogeochem. processes controlling them is important for understanding present and future Arctic emissions.
Here we apply multiply substit...
Autonomous underwater vehicles have been used to characterize Eel Slump, a slide scar located south of Eel Canyon, California. The presence of a well developed dendritic network on the headwall with gullies tens of meters deep, thick sediment drape cover on the slide scar sole, and the absence of fresh surfaces on the scarp suggest that the mass fa...
Submarine channels are conduits through which turbidity currents and related mass movements transport sediment into the deep sea, thereby playing important roles in the development of continental margins and biogeochemical cycles. To gain a better understanding of submarine channel morphodynamic evolution we explore a variety of channel systems fro...