Abstract:

This dataset contains Photographic data of resuspension analyses performed on sediment cores collected aboard R/V Point Sur cruise PS18-25 from the South and southeast of the Macondo wellhead in the Gulf of Mexico from 2018-05-18 to 2018-05-23. Images were extracted from video footage of flume analyses of erosion processes of surface sediments from sediment cores. Images are time series of particles being moved passed the camera that was mounted on the side of the sedflume, taking 30 images per second video footage of the channel, with its focal center in the center of the channel. The dataset includes the station, date and location of the sample collection. In addition, the dataset contains CNT files with the information on the image analysis that includes particle attributes of particles as size (mm), their x,y position within the image (mm), and individual characteristics of these particles in mm (perimeter, diameter, longest axis).

Suggested Citation:

Diercks, Arne. 2020. Photographic data of resuspension analyses performed on sediment cores collected aboard R/V Point Sur cruise PS18-25 from the South and southeast of the Macondo wellhead, Gulf of Mexico from 2018-05-18 to 2018-05-23. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-ry85-yq61

Publications:

Diercks, A. R., Romero, I. C., Larson, R. A., Schwing, P., Harris, A., Bosman, S., … Brooks, G. (2021). Resuspension, Redistribution, and Deposition of Oil-Residues to Offshore Depocenters After the Deepwater Horizon Oil Spill. Frontiers in Marine Science, 8. doi:10.3389/fmars.2021.630183

Purpose:

This experiment was done to simulate erosion processes as a result of current speed.

Data Parameters and Units:

The dataset contains multiple folders with Tif image files, cruise documentation detailing locations (longitude and latitude) and dates of sediment collection, and CNT files with the information on the image analysis that includes - Obj#, Area, Aspect, Center-X, Center-Y, Axis (major), Axis (minor), Diameter (max), Diameter (min), Diameter (mean), Radius (max), Radius (min), Perimeter, Radius Ratio, Size (length), Size (width), and Perimeter (ellipse).

Methods:

Deep-sea cores collected during the May 2018 coring cruise aboard the RV Point Sur cruise PS18-25 were inserted from the bottom into a sedflume. The sedflume’s enclosed (internal flow) erosion and transport channel are 5 cm tall and 15cm wide. The inlet pipe is connected to the erosion channel with a 25cm long circular to rectangular flow converter. The core is inserted from underneath through a 10 cm diameter hole in the center of the floor of the flume. The distance of the insertion opening is 120 cm downstream from the flow converter, to ensure fully developed turbulent flow over the sediment core. The entire flume is a closed system during operation. A sediment core that contains overlying water in the core tube, is inserted from underneath through an O-ring sealed opening into the empty flume. The flume is being filled from a 100-gallon water reservoir and the water is filtered during operation and recirculated in the system. At the end of the sample run, the filtered clean sweater is being returned to the reservoir. During the slow filling of the flume with seawater from the reservoir, the top of the inserted sample core is covered. Once the entire flume is filled with water, the core top cover is removed and the core slowly pushed upward inside the core tube until the sediment-water interface in the core reaches the floor of the flume. The rim of the core tube is kept at level with the floor of the sedflume. Now the access hole of the flume is covered and the remaining air is evacuated out of the system, producing a near closed hydraulic system. The sedflume is a closed channel flow system. A variable speed controllable pump drives the flow through the flume while flow speed is monitored by an impeller driven flowmeter. The flow speed is increased during the experiment while a video camera records footage of the channel downstream of the inserted core. Thus, every particle that is being eroded from the core and being transported downstream is being recorded. The flow speed is increased to a maximum speed of 18 cm/s at which the suspended sediment load is becoming so high that individual grain sizes can no longer be separately identified in the video/images. The recorded video is post-processed into separate TIF images at full resolution. 4 images for every second of the recorded raw video are extracted for particle-sized spectrum analyses.

Instruments:

The model of camera used in the experiment is a Panasonic HC-V180K.

Individual Files: