Sediment Survey: YR070808, Station 3943, Clay Bank, York River Virginia
Virginia Institute of Marine Science
Coastal Hydrodynamics and Sediment Dynamics (CHSD)
All samples contained within (37º39’N, 76º54’W), (37º16’N, 76º20’W), (37º8’N, 76º24’W), (37º34’N, 76º0’W)
This dataset consists of sediment properties including grain size distribution, percent moisture, percent organic matter, sediment bed erodibility, as well as (in most cases) x-ray images of the sediment structure. Most samples were taken in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.
For each cruise, sediment samples were collected using a GOMEX boxcore. The GOMEX allows collection of sea-surface sediment, with little compaction, while retaining the sediment/water interface. Sub cores were taken for different sediment properties. The grain size and percent moisture of the sediment collected in a 10 cm diameter sub-core are determined for 1 cm intervals down core to the depth collected (typically ~10 cm). Two sub-cores were sliced and each corresponding cm interval of the sub-cores was combined to provide enough material for further analysis. The sediment for grain size analysis was disaggregated and the fractions separated by 850 μm and 63 μm sieves for debris fraction >850 μm and sand size fraction. Pipette analysis of material <63 >μm was used to separate the silt and clay fractions. The data file includes the organic content associated with each fraction as determined by loss on ignition in a 550°C oven. The grain size data is expressed at a percentage of the total weight of all the fractions of the sample, on a dry weight basis, dried in a 103-105°C . The percent moisture gives the percent loss, on a wet weight basis, on drying each sample in a 103-105°C. The GUST Microcosm was used to determine the eroded mass, a measure of the surface sediment erodibility, in a 10 cm diameter core over a stepwise series of stresses from 0.01 – 0.56 Pascals (i.e., Dickhudt 2008). The X-ray images are of sediment, collected to depth with a rectangular core (11.5 cm wide X 2.5 cm deep X 11 cm tall ), using a MinXray HF100+ ultralight ET1161 X-ray source and digitally captured with a Scil IPS Image processing board and software.
List of files:
• Gust Erodibility – This folder includes raw and processed data for sediment bed erodibility. MATLAB m-files for processing are also included. If this folder is absent in the dataset, this parameter was not collected.
• Grain Size – This folder includes raw data in the form of an excel file for sediment grain size distribution. For samples after 2010, most data include percent resilient fecal pellet abundance of the sediment as well. If the data are processed, MATLAB m-files are also included. For earlier samples, moisture data may be included in the same file, rather than in its own folder. If this folder is absent in the dataset, this parameter was not collected.
• Moisture – This folder includes raw data in the form on an Excel file for percent moisture and for percent organic matter of the sediment. If the data are processed, MATLAB m-files are also included. If this folder is absent in the dataset, this parameter was not collected.
• X-Rays – This folder includes x-ray images of sediment and (in some cases) raw images of the x-ray core. X-ray images between YR060502 and YR071017 can be view in Dickhudt (2008)(linked in Associated Publications). Otherwise, if this folder is absent in the dataset, this parameter was not collected.
• CTD – This folder includes all raw CTD data from each deployment. If data were processed, MATLAB m-files for processing are also included. If this folder is absent in the dataset, this parameter was not collected.
• LISST – This folder includes all raw and processed data from each deployment where the LISST was available in a flow-through configuration from one of the Gust microcosms. MATLAB m-files for processing are also included. If this folder is absent in the dataset, this parameter was not collected.
• Logbook – Hand-written field notes and instrument setup documents. This file also contains the deployment log of locations and samples taken during the cruise. All field notes and complications/observations are included here.
Sediment transport, grain size distribution, percent moisture, organic content, Gust erodibility, Gust microcosm, sediment erosion, LISST, x-radiograph, x-ray images, sediment structure, CTD
Master Sampling Spreadsheet and Timeline for MUDBED Project Tripod Deployment: YR070612 to YR070830, ADV, Clay Bank, York River Virginia
Grace M. Massey ORCID ID: 0000-0001-7936-1586
Patrick J. Dickhudt ORCID ID: 0000-0001-8003-7089
Carl T. Friedrichs ORCID ID: 0000-0002-1810-900X
NSF grants OCE-0536572, OCE-1061781, and OCE-1459708
Massey, G.M., Dickhudt, P.J., and Friedrichs, C.T., 2022. Sediment Survey: YR070808, Station 3943, Clay Bank, York River Virginia. Virginia Institute of Marine Science, William & Mary.