My research in seismic oceanography aims to quantify useful oceanographic information captured with seismic data. Specifically:

1.  Optimal imaging techniques

2.  Estimating turbulent diffusivity from seismic images

3.  Obtaining accurate temperature and salinity information via

        seismic inversion

#1: Imaging

#2: Turbulence

#3: Temperature

     and Salinity

First, we take displacement and seismic slope spectra of the data.  Some regions are dominated by internal waves, others by turbulence. This provides levels of internal wave and turbulent energy. 

We also invert the seismic data using a combination of global and local inversion methods to produce sound speed profiles at every horizontally sampled location [Padhi et al., 2015]. 

Using this approach I have developed a method to create maps of turbulence throughout the entire water column at a resolution of 400 m laterally and 10 m vertically. 

These inversion results are then converted to temperature and salinity.  Note that this dataset is not the same as the one on the left. 

In a 1-D sense this looks like

Applying this technique to synthetic seismic data we can reliably recover turbulent energy imposed on a background of internal wave energy.  Top figure below is imposed turbulence perturbation and bottom figure is recovered result

The above image shows lee waves in the western Caribbean. They appear in the seismic image as vertically coherent disruptions, seen at 40 and 45 km.

Careful processing of seismic data is necessary before attributes like diffusivity, temperature, and salinity can be recovered. This requires concurrently collected oceanographic data or detailed velocity analysis [Fortin and Holbrook, 2009]. Then we can obtain attributes:

Seismic image processed using Paradigm Geophysical’s Echos software. www.PDGM.com