Applied Marine Exploration

Open PhD position

Ernst Uzhansky

PhD candidate

Ernst Uzhansky is a PhD student in the Department of Marine Geosciences.

He graduated his B.Sc. in Nuclear Physics and Technology from the Voronezh State University (Russia) in 2015, joined the research group in 2015, for his master’s under the supervision of Prof. Boris Katsnelson, Dr. Regina Katsman and Prof. Ilia Ostrovsky. Ernst’s master research “Estimation of gassy sediment parameters using remote acoustical methods: Lake Kinneret , North of Israel as a case study” investigated the upper sediment of Lake Kinneret, with special attention to application of log-to-mid frequency chirp pulses to obtain sound speed and corresponding free gas (methane) content in upper 1 m of the bottom. Attempt to estimate thickness of the layer was made based on study of frequency characteristics of interference structure of received sound field.

Current research

Ernst’s PhD research interests include acoustic sediment characterization (both lake and Mediterranean), study of reverberation and effect of other inhomogeneities (e.g. Kelvin Waves, toxic Cyanobacteria Microcystis) on short- and long-range sound propagation. The project with Dr. Yizhaq Makovsky uses gathering of acoustic data (with AUV, Vertical Line Arrays of hydrophones, various sound transducers), processing and analysis of commercial multi-channel seismic data, building of mathematical models and writing computer codes to determine such important geo-acoustic parameters of the uppermost sediment layer as 1) compressional sound speed, 2) attenuation and 3) roughness.

Numerical model of Transmission Loss along the transect TA at four moments of time. Solid lines represent temperature profile obtained with thermistor chains at Stations H, F, and A and shifted in time by +5 hours. Sound source is depicted as a red circle.

We model sound propagation and compare amplitudes of various arrivals with experimental pulse response to estimate sound speed in the bottom.

As patio-temporal variability of free gas (methane) content estimated on North-Western and Northern transects of Lake Kinneret.

Publications

Uzhansky, E., Makovsky I., Katsnelson B., (2020). Estimating Seafloor Compressional Sound Speed in a Compacting Passive Margin Basin Settings Using Standard Multichannel Seismic Data [in prep].

Uzhansky, E., Katsnelson, B., Lunkov, A., & Ostrovsky, I. (2020). Spatial and temporal variability of free gas content in shallow sediments: Lake Kinneret as a case study. Geo-Marine Letters. https://doi.org/10.1007/s00367-019-00629-4

Liu, L., Sotiri, K., Dück, Y., Hilgert, S., Ostrovsky, I., Uzhansky, E., R. Katsman, B. Katsnelson, R. Bookman, J. Wilkinson, Lorke, A. (2019). The control of sediment gas accumulation on spatial distribution of ebullition in Lake Kinneret. Geo-Marine Letters. https://doi.org/10.1007/s00367-019-00612-z

Page updated

Report abuse