Now showing items 21-40 of 222

    • Performance review of AK regional seismic network for 2019-2021 with focus on field site telemetry and power

      Ruppert, Natalia; Holtkamp, Stephen; Murphy, Nate (2022-02-15)
      We analyzed Alaska Earthquake Center's field sensor network performance for the time period between October 2019 and September 2021. We report on data completeness and acquisition latencies depending on the site power and data communications types.
    • Alaska Earthquake Center Quarterly Technical Report October-December 2021

      Ruppert, Natalia; Gardine, Lea; Gardine, Matt; Grassi, Beth; Holtkamp, Stephen; McFarlin, Heather; West, Michael; Wiser, Samantha (2021-02-15)
      This series of technical quarterly reports from the Alaska Earthquake Center (AEC) includes detailed summaries and updates on Alaska seismicity, the AEC seismic network and stations, field work, our social media presence, and lists publications and presentations by AEC staff. Multiple AEC staff members contributed to this report. It is issued in the following month after the completion of each quarter Q1: January-March, Q2: April-June, Q3: July-September, and Q4: October-December.
    • Alaska Earthquake Center Quarterly Technical Report July-September 2021

      Ruppert, Natalia (2021-11)
      This series of technical quarterly reports from the Alaska Earthquake Center (AEC) includes detailed summaries and updates on Alaska seismicity, the AEC seismic network and stations, field work, our social media presence, and lists publications and presentations by AEC staff. Multiple AEC staff members contributed to this report. It is issued in the following month after the completion of each quarter Q1: January-March, Q2: April-June, Q3: July-September, and Q4: October-December.
    • Sustaining USArray Capabilities in Alaska

      West, Michael (Alaska Earthquake Center, 2018-05)
    • Alaska Earthquake Center Quarterly Technical Report April-June 2021

      Ruppert, Natalia (2021-08)
      This series of technical quarterly reports from the Alaska Earthquake Center (AEC) includes detailed summaries and updates on Alaska seismicity, the AEC seismic network and stations, field work, our social media presence, and lists publications and presentations by AEC staff. Multiple AEC staff members contributed to this report. It is issued in the following month after the completion of each quarter Q1: January-March, Q2: April-June, Q3: July-September, and Q4: October-December.
    • AACSE earthquake catalog: January-August, 2019

      Ruppert, Natalia; Barcheck, Grace; Abers, Geoffrey (2021-05)
      The Alaska Amphibious Community Seismic Experiment (AACSE) comprised 75 ocean bottom seismometers and 30 land stations and covered about 650 km along the segment of the subduction zone that includes Kodiak Island, the Alaska Peninsula and the Shumagin Islands between May 2018 and September 2019. This unprecedented offshore dataset has the potential to support a greatly enhanced earthquake catalog by both increasing the number of detected earthquakes and improving the accuracy of their source parameters. We use all available regional and AACSE campaign seismic data to compile an enhanced earthquake catalog for the region between Kodiak and Shumagin Islands including Alaska Peninsula (51-59N, 148-163W). We apply the same processing and reporting standards to additional picks and events as the Alaska Earthquake Center currently use for compilation of the authoritative regional earthquake catalog. This release includes earthquake catalogs for the time period between January 01 and August 31, 2019. We include monthly CSS database tables (aecevent, arrival, assoc, event, netmag, origerr, origin) and quakeml files. This material is based upon work supported by the U.S. Geological Survey under Grant No. G20AP00026. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the opinions or policies of the U.S. Geological Survey. Mention of trade names or commercial products does not constitute their endorsement by the U.S. Geological Survey.
    • Alaska Earthquake Center Quarterly Technical Report January-March 2021

      Ruppert, Natalia (2021-05)
      This is the first in a series of technical quarterly reports from the Alaska Earthquake Center (AEC). It includes detailed summaries and updates on Alaska seismicity, the AEC seismic network and stations, field work, our social media presence, and lists publications and presentations by AEC staff. Multiple AEC staff members contributed to this report. It is issued in the following month after the completion of each quarter Q1: January-March, Q2: April-June, Q3: July-September, and Q4: October-December.
    • Alaska Earthquake Center: A 2020 Perspective

      Grassi, Beth; West, Michael; Gardine, Lea (2021-03)
      The Alaska Earthquake Center is not historically in the habit of producing annual reports. We are in a dynamic time, however. Societally-significant earthquakes and multiple tsunami concerns over the past few years have brought more attention to what we do. At the same time, we are experiencing significant growth in several areas. Our goal in distributing this summary is to communicate the breadth of our activities and the diversity of our stakeholders, helping us become even more effective at meeting the earthquake and tsunami science needs of Alaska and the nation.
    • Supplemental materials and data products for "The 1964 Mw 9.2 Alaska earthquake: source estimation and predicted ground motion"

      Tape, Carl; Thio, Hong Kie (2021-03-02)
      This collection is established as a placeholder for forthcoming data products and supplemental analysis of a seismological study.
    • 2020 Alaska Seismicity Summary

      Ruppert, Natalia A.; Gardine, Lea (2021-02)
      The Alaska Earthquake Center reported about 49,250 seismic events in Alaska and neighboring regions in 2020. The largest earthquake was a magnitude 7.8 event that occurred on July 22 in the Shumagin Islands region. It was followed by about 6,000 aftershocks including a magnitude 7.6 event on October 19. Other active spots include the 2018 M7.1 Anchorage, 2018 M6.4 Kaktovik, 2018 M7.9 Offshore Kodiak aftershock sequences, Purcell Mountains earthquake swarm, and Wright Glacier cluster northeast of Juneau.
    • Response of an asymmetrical five-story building in Fairbanks, Alaska during the November 30, 2018 M7.1 Anchorage, Alaska earthquake

      Celebi, Mehmet; Ruppert, Natalia (2021-02)
      A recently constructed, five-story, asymmetrical steel building on the campus of the University of Alaska, Fairbanks was equipped with a strong-motion array that recorded the M7.1 Anchorage earthquake of November 30, 2018 at an epicentral distance of 408 km. The largest recorded peak accelerations at the basement and top of the building are 0.021g and 0.071g, respectively. The steel building is designed with several bays that utilize K-shaped buckling restrained braces. The building response records allow identification of fundamental periods (frequencies) as 0.73s (1.4 Hz), 0.63s (1.60 Hz), and 0.56s (1.78 Hz) in the NS, EW, and torsional directions, respectively. System identification computations resulted in estimated critical damping percentages as 7.7% and 4.7 % in the NS and EW directions, respectively. At this low-level of shaking, the building is not expected to (and did not) experience observable damage, which is confirmed with very small average drift ratios. This is the first time a seismic response from this structural array has been analyzed.
    • Alaska Earthquakes Poster

      Gardine, Lea; West, Michael; Grassi, Beth (2020-10)
      Alaska is one of the most seismically active places in the world. This poster connects the geographic distribution of earthquakes from the Alaska Earthquake Center catalog with the core concepts that drive Alaska seismicity. Rupture patches, how plate tectonics forms faults throughout Alaska, and how the angle of the sinking Pacific Plate affects earthquake distribution and creates volcanoes are some of the key concepts represented.
    • AACSE earthquake catalog: May-December, 2018

      Ruppert, Natalia A.; Barcheck, Grace; Abers, Geoffrey A. (2021-02)
      The Alaska Amphibious Community Seismic Experiment (AACSE) comprised 75 ocean bottom seismometers and 30 land stations and covered about 650 km along the segment of the subduction zone that includes Kodiak Island, the Alaska Peninsula and the Shumagin Islands between May, 2018 and September, 2019 (Barcheck et al., 2020). This unprecedented dataset has the potential to support a greatly enhanced earthquake catalog by both increasing the number of detected earthquakes and improving the accuracy of their source parameters. We use all available regional and AACSE campaign seismic data to compile an enhanced earthquake catalog for the region between Kodiak and Shumagin Islands including Alaska Peninsula (51-59N, 148-163W). We apply the same processing and reporting standards to additional picks and seismic events as the Alaska Earthquake Center currently use for compilation of the authoritative regional earthquake catalog. This release includes earthquake catalogs for the time period between May 12 and December 31, 2018 (3829 events total 1132 of which are newly detected). We include monthly CSS database tables and quakeml files. This material is based upon work supported by the U.S. Geological Survey under Grant No. G20AP00026. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the opinions or policies of the U.S. Geological Survey. Mention of trade names or commercial products does not constitute their endorsement by the U.S. Geological Survey.
    • Gas and particle data from Fairbanks during the winter of 2019/2020

      Simpson, William; Cesler-Maloney, Meeta (N/A, 2020-09-30)
      This repository contains data from the relocatable air monitoring system (RAMS) trailer, which measured air pollution around sites in the Fairbanks North Star Borough (FNSB), Alaska. Measured pollutants were: SO2, CO, CO2, and particulate matter (PM). We additionally measured meteorological parameters such as temperatures, winds, and vertical differences in temperatures across an 11-meter tall tower.
    • Preliminary Summary of Barry Arm Seismic Installations

      West, Michael (2020-09-18)
      In September 2020, the Alaska Earthquake Center installed two seismic stations, one webcam, and a repeater in the Barry Arm region of Prince William Sound. This preliminary summary includes descriptions of the instrumentation as well as some very early observations in the data.
    • EarthScope publications database

      Sims, Nealey; Tasa, Keir; Larsen, Jessica; Tape, Carl (2020-08-04)
      We compile a database of EarthScope science publications though May 11, 2020. The database is preserved as a Google Scholar profile available at https://scholar.google.com/citations?user=ZKI-0gUAAAAJ&hl=en&authuser=3
    • PEDESTRIAN TRAVEL-TIME MAPS FOR WHITTIER, ALASKA: An anisotropic model to support tsunami evacuation planning

      Gardine, Lea; Nicolsky, Dmitry (2019-05)
      Tsunami-induced pedestrian evacuation for the community of Whittier is evaluated using an anisotropic modeling approach developed by the U.S. Geological Survey. The method is based on path-distance algorithms and accounts for variations in land cover and directionality in the slope of terrain. We model evacuation of pedestrians to exit points from the tsunami hazard zone boundary. The pedestrian travel is restricted to the roads only. Results presented here are intended to provide guidance to local emergency management agencies for tsunami inundation assessment, evacuation planning, and public education to mitigate future tsunami hazards.
    • PEDESTRIAN TRAVEL-TIME MAPS FOR SITKA, ALASKA: An anisotropic model to support tsunami evacuation planning

      Macpherson, Amy; Gardine, Lea; Nicolsky, Dmitry (2020-06)
      Tsunami-induced pedestrian evacuation for Sitka is evaluated using an anisotropic modeling approach developed by the U.S. Geological Survey. The method is based on path-distance algorithms and accounts for variations in land cover and directionality in the slope of terrain. We model evacuation of pedestrians to exit points from the tsunami hazard zone. The pedestrian travel is restricted to the roads only. Results presented here are intended to provide guidance to local emergency management agencies for tsunami inundation assessment, evacuation planning, and public education to mitigate future tsunami hazards.
    • PEDESTRIAN TRAVEL-TIME MAPS FOR PERRYVILLE, ALASKA: An anisotropic model to support tsunami evacuation planning

      Gardine, Lea; Nicolsky, Dmitry (2019-08)
      Tsunami-induced pedestrian evacuation for the community of Perryville is evaluated using an anisotropic modeling approach developed by the U.S. Geological Survey. The method is based on path-distance algorithms and accounts for variations in land cover and directionality in the slope of terrain. We model evacuation of pedestrians to exit points located at the tsunami hazard zone boundary. Pedestrian travel-time maps are computed for two cases: i) travel to an existing evacuating shelter and ii) travel to either the evacuation or an alternative shelter. Results presented here are intended to provide guidance to local emergency management agencies for tsunami inundation assessment, evacuation planning, and public education to mitigate future tsunami hazards.
    • PEDESTRIAN TRAVEL-TIME MAPS FOR CORDOVA, ALASKA: An anisotropic model to support tsunami evacuation planning

      Macpherson, Amy; Gardine, Lea; Nicolsky, Dmitry (2020-06)
      Tsunami-induced pedestrian evacuation for Cordova is evaluated using an anisotropic modeling approach developed by the U.S. Geological Survey. The method is based on path-distance algorithms and accounts for variations in land cover and directionality in the slope of terrain. We model evacuation of pedestrians to exit points from the tsunami hazard zone. The pedestrian travel is restricted to the roads only. Results presented here are intended to provide guidance to local emergency management agencies for tsunami inundation assessment, evacuation planning, and public education to mitigate future tsunami hazards.