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Abstract Geological processes at subduction zones and their associated geohazards (e.g., megathrust earthquakes, submarine landslides, tsunamis, and arc volcanism) are, to a large extent, controlled by the structure, physical properties and fluid content of the subducting plate, the accreted sediments, and the overriding plate. In these settings, modern seismic modeling and imaging techniques based on controlled-source, multicomponent ocean-bottom seismometer (OBS) data are some of the best tools available for determining the subseafloor elastic properties, which can be linked to the aforementioned properties. Here, we present CASIE21-OBS, a controlled-source marine wide-angle OBS data set recently collected across the Cascadia convergent margin as part of the larger CAscadia Seismic Imaging Experiment 2021 (CASIE21). The main component of CASIE21 is a long-offset multichannel seismic (MCS) survey of the Cascadia margin conducted in June–July 2021 onboard R/V M.G. Langseth (cruise MGL2104) aiming to characterize the incoming plate, the plate interface geometry and properties, and the overlying sediment stratigraphy and physical properties. CASIE21-OBS was conducted during R/V M.G. Langseth cruise MGL2103 (May 2021) and R/V Oceanus cruise OC2106A (June–July 2021). It consisted of 63 short-period four-component OBSs deployed at a total 120 stations along 10 across-trench profiles extending from ∼50 km seaward of the deformation front to the continental shelf, and from offshore northern Vancouver Island to offshore southern Oregon. The OBSs recorded the airgun signals of the CASIE21-MCS survey as well as natural seismicity occurring during the deployment period (24 May 2021 19:00 UTC–9 July 2021 09:00 UTC). The OBS data are archived and available at the Incorporated Research Institutions for Seismology Data Management Center under network code YR_2021 for continuous time series (miniSEED) and identifier 21-008 for assembled data set (SEG-Y).
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Alaskan Beaufort Shelf Sediment Study – Harrison Bay: Geotechnical Properties from a Portable Free-Fall Penetrometer and Erodibility Assessment, 2021-2022
This dataset comprises the geotechnical data from a series of surveys conducted in Harrison Bay, Alaska in July/August of 2021 and 2021. The contribution of this specific dataset to the overall project goals was connecting geotechnical sediment properties to erodibility parameters in an Arctic coastal environment. During the 2021 survey, geotechnical sediment properties from a portable-free fall penetrometer (PFFP) were related to physical sampling to develop a regional sediment classification scheme, and the data collected during the 2022 survey aimed to connect the results from the previous year to laboratory-based erodibility parameters from the Jet Erosion Test (JET), which was conducted on gravity core samples taken from the site. The attached repository contains both raw and processed data, and the specifics of the file structure can be found in the readMe.txt file.
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- PAR ID:
- 10635167
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- Geotechnical Portable Free-fall Penetrometer Jet Erosion Test Harrison Bay Erosion
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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