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FlocARAZI: An In-Situ, Image-Based Profiling Instrument for Sizing Solid and Flocculated Suspended Sediment

Osborn, Ryan and Dillon, Brandon and Tran, Duc and Abolfazli, Ehsan and Dunne, Kieran B. J. and Nittrouer, Jeffrey A. and Strom, Kyle (2021) FlocARAZI: An In-Situ, Image-Based Profiling Instrument for Sizing Solid and Flocculated Suspended Sediment. Journal of Geophysical Research. Earth Surface, 126 (11). Art. No. e2021JF006210. ISSN 2169-9003. doi:10.1029/2021JF006210.

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An inexpensive and compact underwater digital camera imaging system was developed to collect in situ high resolution images of flocculated suspended sediment at depths of up to 60 meters. The camera has a field of view of 3.7 × 2.8 mm and can resolve particles down to 5 µm. Depending on the degree of flocculation, the system is capable of accurately sizing particles to concentrations up to 500 mg/L. The system is fast enough to allow for profiling whereby size distributions of suspended particles and flocs can be provided at multiple verticals within the water column over a relatively short amount of time (approximately 15 min for a profile of 15 m). Using output from image processing routines, methods are introduced to estimate the mass suspended sediment concentration (SSC) from the images and to separate identified particles into sand and mud floc populations. The combination of these two methods allows for the size and concentration estimates of each fraction independently. The camera and image analysis methods are used in both the laboratory and the Mississippi River for development and testing. Output from both settings are presented in this study.

Item Type:Article
Related URLs:
URLURL TypeDescription
Osborn, Ryan0000-0002-9978-4639
Dillon, Brandon0000-0003-0087-7331
Abolfazli, Ehsan0000-0001-6830-1270
Nittrouer, Jeffrey A.0000-0002-4762-0157
Strom, Kyle0000-0002-0798-7720
Additional Information:© 2021 American Geophysical Union. Issue Online: 28 October 2021; Version of Record online: 28 October 2021; Accepted manuscript online: 12 October 2021; Manuscript accepted: 08 October 2021; Manuscript revised: 30 September 2021; Manuscript received: 13 April 2021. Funding for this work was provided by the National Science Foundation under EAR award 1801142, “Collaborative Research: Flocculation Dynamics in the Fluvial to Marine Transition.” Additional financial support for R. Osborn was provided by the Charles E. Via, Jr. Endowment at Virginia Tech and the New Horizons Graduate Scholars Program. Three anonymous reviewers are greatly acknowledged for providing comments that help to improve the paper. Data Availability Statement: Data associated with this study is available at or by contacting the corresponding author (
Funding AgencyGrant Number
Virginia Polytechnic Institute and State UniversityUNSPECIFIED
Subject Keywords:Flocculation; Machine Learning; Sediment Transport; Camera System; Particle Sizing
Issue or Number:11
Record Number:CaltechAUTHORS:20211015-222201811
Persistent URL:
Official Citation:Osborn, R., Dillon, B., Tran, D., Abolfazli, E., Dunne, K. B. J., Nittrouer, J. A., & Strom, K. (2021). FlocARAZI: An in-situ, image-based profiling instrument for sizing solid and flocculated suspended sediment. Journal of Geophysical Research: Earth Surface, 126, e2021JF006210.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:111479
Deposited By: George Porter
Deposited On:18 Oct 2021 14:41
Last Modified:24 Nov 2021 18:12

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