The Very High Resolution 3D Seismics project (VHR3D) is aimed at a cost-effective detailed 3D reconnaissance of seabed sediment properties for geological, geotechnical and environmental site investigation purposes, based on very high resolution 3D seismics.
The main objective of the project is twofold :
(1) The development of a flexible 3D seismic method which allows optimal coverage of targets of different size,
(2) The extraction of geotechnical information from the 3D seismic data leading to the creation of a 3D physical model of the subsurface based on the acquired information.
The acquisition of high-quality data is the basis on which the project will depend.
Two complementary systems will be developed : (1) a compact rigid array for targets of limited areal extent (about 100 x 100 m) in very shallow water (< 25m) and with limited penetration (< 50 m), and (2) a dynamic flexible array fortargets of larger size (up to 1 x 1 km) in water depths up to 100 m andallowing a deeper penetration (about 100 m). Data acquisition will be performed in sites which have already been investigated.
Basic processing steps will include navigation geometry, signal analysis, static corrections and binning. Imaging will be performed using stacking and migration techniques. A subset of the 3D data volume will be treated for seismo-acoustic attribute information (velocity, attenuation, impedance). Empirical relationships between the acoustic parameters and geotechnical properties will be used to develop algorithms to invert the seismo-acoustic responses. Laboratory measurements will provide calibration data. Ultimately it will be possible to obtain a 3D model of the physical and geotechnical properties of the study site.
Synthetic seismograms and groundtruth information will validate the feasibility of the methodology.
A practical guide of specifications will be set up for economic use of the VHR3D method, in order to assure optimum applicability of this method and to increase its competitiveness and market potential.
Funding SchemeCSC - Cost-sharing contracts
GU21 3LF Woking - Surey
LL59 5EY Gwynedd