Dr Florian Lepape
- Postdoctoral Researcher
Florian Le Pape is a post-doc researcher in the iCRAG marine research spoke. Florian graduated in geophysics from EOST Strasbourg in 2008 and then moved to DIAS for his PhD to work on the dynamics of the Tibetan plateau. He obtained his PhD in 2012 and then focused on the lithosphere imaging of the Leo-man shield in West Africa. Within iCRAG, he will be working with Prof C. Bean to investigate ocean generated microseisms and the associated acoustic/seismic coupling at the sea bed. General research interests include ocean related acoustic/seismic noise, crust and lithosphere imaging, magnetotellurics, physical properties and rheology.
In addition to earthquakes, a seismogram can tell you a lot about the Earth. In this research, I focus on the study of ocean wave induced ground vibrations also defined as seismic ambient noise which represents a continuous background noise on seismic recordings. I look at how ocean related ground vibrations are generated and propagate in deep and shallow water to the land. The use of seismic ambient noise is becoming more and more significant as a passive technique (the source is the ocean!) for imaging and monitoring the Earth structure at different scales, but also for studying the ocean wave climate.
Project title: Novel applications of broad band near sea floor pressure/acoustic monitoring for time lapse remote sensing of sea-bed processes
With the use of ‘ambient noise correlation’ techniques for broad (regional) scale seismic passive imagery and time-lapse monitoring (e.g. in reservoirs), understanding ocean generated seismic noise sources or also called microseisms is very important. Microseisms can also be used for ocean storm tracking and for determining areas of maximum cyclical pressure fluctuations on the sea floor. In order to study what controls the generation and propagation of ocean induced ambient seismic noise from ocean to land, I look at acoustic and seismic data recorded on the seafloor and how it compares with numerical simulations. This research project includes the deployment in the continental shelf offshore Donegal and in the Rockall Trough of a sea floor acoustic/seismic monitoring network including Ocean Bottom Seismometers (OBS) and hydrophones in order to map the temporal acoustic and associated seismic landscape at low frequencies, and particularly ocean waves to sea floor interaction. In addition to the collected acoustic and seismic data, numerical simulations of acoustic/seismic wave propagation forms an important element of the work. Combining observations with 3D simulations appears significant to better understand what control the acoustic/seismic coupling at the sea floor as well as the effect of the water column and sediments thicknesses on signal propagation.
- Postdoctoral Researcher
- Earth System Change
- Geomarine Environment