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  • The literature covered in this report was gathered and reviewed as background for the DCC Curation Lifecycle Model 2.0 project. Led by Sayeed Choudhury at Johns Hopkins University and funded by the Alfred P. Sloan Foundation, the project provided a foundation for updating the original DCC model, originally published in 2008. A revised model is needed to accommodate the dramatic changes in the context of data production and use, and the associated impact on data archives and repositories.
    Data Types:
    • Document
  • The literature covered in this report was gathered and reviewed as background for the DCC Curation Lifecycle Model 2.0 project. Led by Sayeed Choudhury at Johns Hopkins University and funded by the Alfred P. Sloan Foundation, the project provided a foundation for updating the original DCC model, originally published in 2008. A revised model is needed to accommodate the dramatic changes in the context of data production and use, and the associated impact on data archives and repositories.
    Data Types:
    • Document
  • Emoticons have emerged as a strong means of enhancing text-based communication, and cross-cultural understanding is important in framing emoticon research. This paper provides a cross-cultural comparison of emoticons by reviewing publications and webpages in English, Chinese, and Japanese. To our knowledge, it is the most comprehensive survey of its type, covering well over 100 papers, including some which have never been translated into English. Note that since this paper was written in 2015, our survey focuses on research published before 2015. We also provide a detailed history of the origins of emoticon use. Our hope is to provide a useful resource for researchers to understand early efforts in the field, and foster continued research in emoticons as used in computer-mediated communication (CMC).
    Data Types:
    • Other
  • Using 24 public shared novel coronavirus (nCoV) genomes, we examined genetic diversity to infer date of common ancestor and rate of spread. We find: 24 sampled genomes are nearly identical, differing by 0-3 mutations This lack of genetic diversity has a parsimonious explanation that the outbreak descends either from a single introduction into the human population or a small number of animal to human transmissions of very similar viruses. This event most likely occurred in November or early December 2019. There has been ongoing human-to-human spread since this point resulting in observed cases. Using estimates of total case count from Imperial College London of several thousand cases, we infer a reproductive number between 1.5 and 3.5 indicating rapid growth in the Nov-Jan period.
    Data Types:
    • Other
  • The 6.8 magnitude Nisqually earthquake occurred on February 28th, 2001 causing liquefaction in multiple areas of Seattle, mostly in the SoDo neighborhood. Following the earthquake, scientists recorded field observations of the liquefaction in Seattle, which was compiled into a database. While the SoDo neighborhood is mapped as having the same liquefaction potential throughout, large areas did not show above-ground signs of liquefaction, such as sand boils. I looked at the subsurface in areas where sand boils were reported and in areas where no sand boils were reported to determine if significant geologic differences occur in the subsurface that could explain why liquefaction occurred in some areas and not others. The study area has undergone multiple glaciations, and is part of the former Duwamish River delta, occupying a former subglacial trough. In the last century, humans have modified the delta and associated tide flats to expand buildable land by adding variable thicknesses of fill, primarily sourced from nearby glacial deposits. To examine the subsurface, I used the GeoMapNW subsurface database to find borings adjacent to sand boils and borings at sites where sand boils were not reported. I identified target locations, where sand boils did and did not occur, and where good subsurface data are available. I compared the subsurface stratigraphy to depths of 40 feet from selected borings in the target areas and looked at density, sand content and clay content. I also compared the ratio of the thickness of fine-grained sediment to coarse-grained sediment. To compare the densities of the subsurface, I performed clean sand corrections and performed modeling to generate a Liquefaction Potential Index (LPI) at the target locations. I found that areas with capping clay layers at/near the surface of greater than 3ft in thickness or significant amounts of clay within the upper 40 feet were more common in areas where no sand boils were reported. I also found that areas where no sand boils were reported typically had higher ratios of fine-grained thickness to total thickness, and that these ratios were higher in the eastern portion of the site area. The LPIs at borings adjacent to sand boils were calculated to be high risk or very high risk. The LPIs for the borings chosen in areas where there were no sand boils ranged from low risk to very high risk. Some of the high or very high risk boring locations had caps of clay or near surface layers had undergone construction-related compaction, which may have resulted in liquefaction not reaching the surface and instead potentially spreading laterally. For the Nisqually earthquake the LPI alone does not adequately predict whether or not liquefaction will occur at the ground surface in the SoDo area due to geologic or human-influenced variability. LPI will over predict liquefaction at the ground surface for the SoDo area.
    Data Types:
    • Other
  • In 1996, 2007, and 2009, flooding of the Chehalis River near the Town of Chehalis in southwest Washington severely impacted infrastructure and property. Damage was such that Interstate 5, the major transportation throughway in this region, was closed for several days. In 2012, the Washington State Geological Survey and United States Geological Survey began an assessment of the seismic hazards posed by the regional and local geologic systems on proposed construction of a dam near the Town of Pe Ell, Washington. Of these structural systems, the Doty Fault Zone is of interest as; (1) its level of activity is not well known, (2) its geometry is not described in detail, (3) it extends along a portion of the Chehalis River, and (4) would pose a hazard to the construction of the dam if it were active. The Doty Uplift (DU) is one of several basement uplifts in southwest Washington, and the western extent of the Doty Fault Zone bounds the southern boundary of the DU. In this report, the morphology of streams draining the DU are studied and characterized to identify topographic evidence of active deformation associated with the Doty Fault Zone. I performed a digital analysis of the morphology of twenty-two streams, including the description of channel steepness and longitudinal-profile geometry and the identification of knickpoints, or locations of sharp changes in the channel slope along each river. The influence of lithology and the discrimination between discrete (fault-related) and persistent (anticlinal and lithologic) forcings were considered in the analysis. Patterns in the normalized channel steepness index (ksn) across the study site show increasing ksn values moving upstream along drainages within the DU. These range from less than ~150m on the outer margins of the DU to ~400m within it. Anomalous high ksn values that rise to up to 800m point to areas on long profiles that may be identified as knickpoints. Ten knickpoints found within the DU are identified, located between elevations of 137 and 320 meters. They range in size from ~4-meter-deep steps to 36 meter near-vertical drops over distances that range between 6 and 45 meters. Nine of the knickpoints are located at higher elevations that the Doty Fault, yet they do not form similar geometries at similar elevations. In addition, the location of the knickpoints in relation to lithologic boundaries and mass wasting deposits introduces complicating factors that make tying these features to fault-related formation tenuous. Six knickpoints are located within the Crescent Formation, three are located within sedimentary units, and one at a lithologic boundary where streams cross over rocks of variable resistances. The lack of spatial continuity and differences in knickpoint form does not point to the influence of an active Doty Fault. The spatial patterns of normalized channel steepness indices and knickpoints within and around the DU do not point to discrete, fault-offset related causes. Instead, they are likely the product of the structural signature of the Crescent Formation, accented by the influence of lithologic boundaries and mass-wasting deposits. Further investigations of the adjustment of streams of the Doty Hills, thorough in-channel surveys and wider-scale basin instability analyses would help elucidate the topographic evolution of this area.
    Data Types:
    • Other
  • Only a few strands of the Seattle Fault Zone have been identified on land in Seattle, Washington due to heavy manipulation of the landscape by repeat glaciations, geomorphic reworking, and the interference of the growing metropolitan community concealing potentially dangerous active faults below the surface. Previous difficulty locating faults on the ground surface led to the idea of using geotechnical boring logs to ìsee intoî the subsurface structure. Can the depth to the contact between Quaternary deposits and Tertiary bedrock, obtained from existing geotechnical boring logs, be used to predict the locations of fault strands in the Seattle Fault Zone in Seattle? The University of Washington Pacific Northwest Center for Geologic Mapping Studies (GeoMapNW) database contains thousands of geotechnical boring logs readily available. Over 18,000 boring logs were processed using the computer programming language Python to select boring logs containing bedrock-related terms describing Blakely Harbor Formation, Blakeley Formation, Tukwila Formation, and any other bedrock in Seattle. This process isolated 1700 boreholes that potentially intersected bedrock. Each of the 1700 boring logs were individually categorized to determine if the Python code was valid. This process reduced the queried boring logs to 809 boreholes containing bedrock within the Seattle Fault Zone. The boreholes containing bedrock were used to construct preliminary contours of the bedrock surface in AutoCAD Civil 3D. Both boreholes containing bedrock and boreholes not containing bedrock were used to generate 108 geologic cross sections using the geographic information system (GIS) Geologic Cross Section Toolbox developed in 2018. The variation in depth to the contact between Quaternary deposits and Tertiary bedrock was evaluated in the cross sections highlighting 66 anomalies in southeast Seattle. The anomalies were checked against the triangular irregular network (TIN) surface and contours generated in AutoCAD Civil 3D to better visualize the Seattle Fault Zone structure. The anomalies ranged from potential faults and geomorphic alterations to possible human alterations such as hillslope grading along Interstate 5. Fifty percent of the anomalies were identified as potential faults based on the continuation of offset patterns in neighboring cross section. Published fault locations from multiple reliable sources supplied by the U.S. Geological Survey (USGS) and Washington State Department of Natural Resources (DNR) were checked to assess the connection of anomalies to mapped faults. Some of the anomalies found through borehole correlation suggest revisions and continuations of existing published fault locations through the City of Seattle. Identifying potential fault anomalies by correlating detailed boring logs proved successful and could be applied to complex fault zones worldwide. The next step is to investigate the anomalies identified as potential faults to determine if they are representations of faults strands within the Seattle Fault Zone.
    Data Types:
    • Other
  • This research examines terrestrial-laser scan data on a road cut in the Glitter Gulch area of Alaska, immediately preceding and following a slope stabilization project, noting changes in rock fall and comparing the work done during excavation to the hazardous areas identified through the "Rockfall Activity Index (RAI) model (Dunham et al., 2017). Using the RAI for the study we may also determine its efficacy by noting if the model identified the same high hazard areas as engineers. In this report, I compare RAI predictions of future failure with on-the-ground assessments of hazard as indicated by scaling activity.
    Data Types:
    • Other
  • A tombolo may have tied a bedrock knoll at the western tip of Alki Point to the mainland before a large magnitude 7 or greater earthquake ruptured within the Seattle fault zone, resulting in ~23 ft of uplift at Alki Point and exposing shallow beach/intertidal deposits. The purpose of this study was to (1) reconstruct the geomorphology of Alki Point during the mid-late Holocene in order to understand the conditions under which marsh deposits at Alki Point were formed, and (2) partially characterize the spatial variability of marsh deposits at Alki Point. The motivation behind this work was to provide future paleoseismic studies a basis as to where reliable paleoenvironmental data within marsh deposits can be found. This data can be used by paleoseismologists to reconstruct the abrupt or gradual nature of environmental changes that may be related to coseismic uplift or other environmental factors. Data from three sites at Alki Point and one at a marsh near Restoration Point on Bainbridge Island include; (1) stratigraphic observations from borings and trench observations, (2) radiocarbon ages, and (3) elevation data from microfossil assemblages. Two-foot contours constructed over LiDAR data for Alki Point show low topographic relief trending northwest-southeast where a tombolo may have connected a bedrock knoll near the western tip of Alki Point to the mainland, with beach ridges shoreward of and parallel to a suspected tombolo. The direction of the shore-drift at Alki Point is from the south, driving the propagation of waves towards the southern shore of Alki Point. These factors would be the most important control on sediment transport, and would have assisted in shaping a tombolo along the southern margin of Alki Point. A sample taken 6 ft above MLLW from a tree log in the middle of a peat layer shoreward of the current beach ridges had a radiocarbon age of 6264 to 6529 cal yr B.P. This would have required that one or more beach ridge(s) were further offshore from where this peat would have deposited in a quiescent intertidal environment. As sea levels rose to near to the present level ~5500-6000 cal yr B.P., the beach ridge(s) would have transgressed to the current position. The formation of a tombolo with shoreward beach ridges may have allowed for one or more marshes to form on Alki Point since shore-drift derived from the south. Ages on beach deposits below the middle peat layer at Alki Playground are between 3078 to 4826 cal yr B.P., and the age on the upper peat layer at Alki Playground is modern (after 1950 AD) to 297 cal yr B.P. This suggests that the middle peat layer encountered at two of the Alki Point sites, was deposited sometime between 297 to 3078 cal yr B.P., after a tombolo would have formed.
    Data Types:
    • Other
  • Collecting cobble counts and gathering cross sections out in the field can be a tedious and time consuming process. An attempt was made at expediting this process using structure from motion technology to create an orthophoto and a digital surface model of the Nisqually riverbed adjacent to Longmire in Mount Rainier National Park. An oblique photoset was gathered of the Nisqually riverbed using a telescoping pole with a digital camera and high-precision GPS mounted at the end of it. This photoset was then used to create a point cloud, an orthophoto, and a digital surface model using Pix4D. Automated cobble counts were gathered using two different Matlab scripts; DigitalGrainSize, and BASEGRAIN. DigitalGrainSize proved to be fairly accurate and may act as a replacement if grain sizes 11 mm and below are not relevant to a study. An automated grain size distribution may be even more accurate if a higher resolution digital surface model is produced or if a single photo is used instead of an orthophoto. BASEGRAIN did not perform as well and did not detect both smaller and larger grain sizes. Cross sections were derived from the digital surface model and have a high resolution when compared to 1 m resolution lidar in the same area. Channels that are only active at higher flows can be seen clearly in the digital surface model cross sections as well. The only drawbacks are that vegetation, and water are included in the digital surface model, so it cannot measure beneath the water’s surface as opposed to a total station, and the elevation was approximately 60 feet lower than actual elevation. This was likely due to a GPS error. I believe that these two applications show promise, especially if these techniques are refined.
    Data Types:
    • Other