Summary Research Interests Curriculum Vitae Other Interests

Mark Vardy

Postgraduate Research Student

Geology & Geophysics Group

Room 186/04

National Oceanography Centre, Southampton

European Way

Southampton

UK

SO14 3ZH

email: mev@noc.soton.ac.uk

phone: +44 (0) 23 80596547

Active Research

Mark Vardy is a third year PhD student, working toward the development of a decimetre-resolution 3D marine seismic system and associated processing strategem. Although recently a large portion of his time has been devoted to testing fundamental shot timing, RTK-GPS positioning, and SEG-Y generation algorithms, his research is generally focused on optimizing the processing of high-resolution, swept-frequency marine seismic data for interpretation purposes.

Particular attention is focussed on sampling of the 3D wavefield, and methods of regularization to accommodate undersampling prior to pre- or post-stack 3D time migration. A combination of forward modelling and controlled environment testing has allowed a variety of different data regularization and imaging algorithms to be compared in terms of their imaging effectiveness and computational cost.

  1. High-resolution marine seismic acquisition.
  2. Seismic convolution theory.
  3. Sampling theorem.
  4. Pre- and post-stack 3D time migration.

These techniques have been successfully applied to shallow water engineering targets in several harbours on the south coast of the UK and Holland, along with a geologically interesting target in Windermere, UK Lake District.

With the engineering targets, the combination of our decimetre resolution, true 3D seismic volume with extensive post-survey dredging confirmed our ability to locate 100% of buried and part-buried targets, and to image them such that post-migration size, shape, and limited acoustic property information can be presented (see Figure below).

Comparison of seismic imaged taget and coincidently dredged object,

(a) Horizon slice and (b-c) vertical slices through acoustic target, together with (d) location map, and (e) photo of the wooden pole (1.80 x 0.13 x 0.10 m) and attached metal sheet (0.40 x 0.30 m) found during dredging. Vertical exaggeration 4:1. Results presented in Vardy et al (2008), Geophysics 73(2), p B33-B40.