This readme.txt file was generated on <2019-05-15> by ------------------- GENERAL INFORMATION ------------------- 1. Title of Dataset Bifurcation experiments: timeseries, images, topographic scans, St. Anthony Falls Laboratory, 2016-2017 2. Author Information Name: Gerard Salter Institution: University of Minnesota Address: St. Anthony Falls Laboratory, 2 3rd Ave. SE, Minneapolis, MN, 55414 Email: salte040@umn.edu Name: Vaughan Voller Institution: University of Minnesota Address: St. Anthony Falls Laboratory, 2 3rd Ave. SE, Minneapolis, MN, 55414 Email: volle001@umn.edu Name: Chris Paola Institution: University of Minnesota Address: 375-04 Tate Hall, University of Minnesota, Minneapolis, MN, 55414 Email: cpaola@umn.edu 3. Date of data collection 2016-09-01 to 2017-04-06 4. Geographic location of data collection (where was data collected?): St. Anthony Falls Laboratory, University of Minnesota 5. Information about funding sources that supported the collection of the data: This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. 00039202. -------------------------- SHARING/ACCESS INFORMATION -------------------------- 1. Licenses/restrictions placed on the data: Attribution-NonCommercial 3.0 United States (CC BY-NC 3.0 US) 2. Links to publications that cite or use the data: Salter, G., Voller, V.R., Paola, C., 2019, How does the downstream boundary affect avulsion dynamics in a laboratory bifurcation?, Earth Surface Dynamics (in review) 3. Links to other publicly accessible locations of the data: N/A 4. Links/relationships to ancillary data sets: N/A 5. Was data derived from another source? No 6. Recommended citation for the data: Salter, Gerard L. (2019). Bifurcation Experiments: Timeseries, Images, Topographic Scans, St. Anthony Falls Laboratory, 2016-2017. Retrieved from the Data Repository for the University of Minnesota, http://hdl.handle.net/11299/202950. Please also cite the associated paper in Earth Surface Dynamics. --------------------- DATA & FILE OVERVIEW --------------------- 1. File List A. Filename: timeseries.zip (5 .xls files) Short description: timeseries of water and sediment fluxes through each branch, timeseries of front positions in each branch Description: Folder contains an excel sheet with timeseries for each of the five experiments (see publication for run parameters). See row 1 for variable names/ units. RL/RR denote river left and river right, respectively. Time interval is 1 second for all data except front positions (20 second time interval for exp 1-4, 30 sec for exp5). Time in file can be used to find correspondence with the raw files. Image # can be used to find correspondence with overhead images. B. Filename: corrected images.zip (27141 .png files) Short description: orthorectified overhead imagery Description: Folder contains orthorectified overhead images of the experiments. Each experiment has its own subfolder. Images are taken every 20 sec for exp 1-4, and 30 sec for exp 5, however, this is complicated by start/stop times and occasional camera malfunctions. Therefore, use the image # column in the timeseries.zip excel sheets to find the run time corresponding to each image. The black bar in the images represents 1 meter. C. Filename: topo scans.zip (.csv) Short description: bed surface and water surface topographic scans. Elevations are in mm, and spacing between data points is 1 mm in both x and y directions. Description: The folder contains a subfolder for each experiment, and an excel sheet for each experiment with the runtimes at which each scan was taken. Within the subfolders, there is a csv file for each scan. Using the scantimes excel sheets, the prefix hourxx can be matched to experiment run time. Bedsurf scans are with the flow turned off, and therefore measure bed topography; watsurf scans are while experiment is running, we add titanium dioxide to make the water opaque, then scan; the result is a scan of the water surface elevation. In the csv files, data points are on a grid with 1 mm spacing, and the z values reported in the csv files are in mm. NaN is the symbol I used for missing data. D. Filename: raw timeseries.zip (5 .xls files) Short description: unprocessed timeseries Description: An excel file is provided for each experiment. The organization in these excel files is that each continuous period of experiment run time is given its own sheet (the flow is turned off for the bed topography scans). These separate sheets are then pieced together manually, after removing ramp up/down times, to create the timeseries in timeseries.zip. Note that a topo scan with prefix hourxx corresponds to the end of the hourxx sheet. NaN is the symbol I used for missing data. Image # is listed in the raw timeseries files. E. Filename: raw images.zip (27157 .jpg files) Short description: non-orthorectified overhead imagery Description: Same as corrected images folder, except no cropping or orthorectification. F. Filename: processing.zip (Matlab 2018b files) Short description: Provides auxiliary data and scripts for computing water flux (through calibration curve), image orthorectification, processing to get sediment flux, and script to find front positions. Description: Contains four subfolders corresponding to different processing steps. Matlab scripts, their dependent functions, and any auxiliary data are provided within each subfolder. Discharge calibration folder is for converting mass on the water scales to discharge through a calibration curve, provided in an excel sheet. The conversion is done in the discharge_converter.m script, and an additional script was needed for exp5. Front positions folder contains script for automatically extracting sediment fronts from overhead images. Image correction folder contains images of the experiment with grid overlaid, an excel sheet with the correction matrices I used (which were manually found using the overhead image), and the matlab script to apply the correction. Sedflux processing folder contains script for converting mass on sediment scale to sediment flux, which involves correcting for changes in water volume and buoyancy. G. Filename: sandpile.zip (2 .mp4 and 1 .xls) Short description: video of sandpile experiment, and excel sheet with avalanche classification/ avalanche time, which was produced manually based on the video. Description: Contains (in two parts) a video of the sandpile experiment, and an excel sheet containing the time and classification of each avalanche (manually recorded from the video). t=1689 s is when the sandpile first reached the overfall. H. Filename: videos.zip (5 .mp4 files) Short description: A video provided for each experiment (five total); top is the overhead imagery, bottom is scrolling plot of water flux partitioning. Description: Contains a video of overhead imagery (top) and scrolling plot of flux partitioning (bottom) for each experiment (five total). 2. Relationship between files: In timeseries.zip, the column "time in raw file (s)" can be used to find the correspondence between times between the raw (raw timeseries.zip) and processed timeseries (times where discharge was ramping up/down between topo scans were manually removed, and then the timeseries were concatenated). In timeseries.zip, the column "image #" can be used to find the overhead image in corrected images.zip corresponding to that time. Auxiliary data/scripts for data processing provided in processing.zip. 3. Additional related data collected that was not included in the current data package: N/A 4. Are there multiple versions of the dataset? yes/no No -------------------------- METHODOLOGICAL INFORMATION -------------------------- 1. Description of methods used for collection/generation of data: Please see publication in Earth Surface Dynamics. 2. Methods for processing the data: Raw timeseries were concatenated, after removing ramp up/down times manually, to form continuous timeseries. A calibration curve was used to convert mass on scales to water discharge. Using known points based on an overlaid grid, overhead images were orthorectified. Sediment fluxes were calculated from sediment scale mass, after correcting for changes in water volume and for bouyancy. Front positions were extracted automatically using a script (some manual cleaning was necessary). 3. Instrument- or software-specific information needed to interpret the data: Matlab (2018b) for processing scripts. 4. Standards and calibration information, if appropriate: N/A 5. Environmental/experimental conditions: Experiments conducted in a custom bifuration flume at St. Anthony Falls Laboratory; see publication for details. 6. Describe any quality-assurance procedures performed on the data: Plotted data to check for internal consistency/consistency with observations. 7. People involved with sample collection, processing, analysis and/or submission: Gerard Salter