Patent ID: 6612397
Filing Date: 2003-09-02
Classification: G01V,Y10S

Abstract:
A seismic shear wave generator device having a seismic source (3), a base plate (11) for being arranged proximate a sea bed, and a coupling device (1) arranged for coupling the wave source (3) mechanically to the sea bed so that shear waves may be transmitted to the sea bed, comprising:a coupling device (1) having a generally vertical skirt (1) around a perimeter of a base plate (11) and extending downwards from the underside of the base plate (11), the skirt having a height and being open downwards; a pump device (2) configured to pump water out of or into the skirt (1), respectively, from or to an enclosed cavity beneath the base plate (11), to form an underpressure or overpressure, respectively, in said cavity, forming a suction anchor delimited by the skirt (1), the base plate (11), and the sea bed when the skirt (1) is lowered to entirely or partly penetrate the sea bed, so as to suction the coupling device of a desired depth before activating the seismic source for generating seismic shear waves, and to release the coupling device from the seabed before moving the seismic shear generator to another location; a valve (4) in the base plate (11) configured to releasably connect with the pump device (2), the pump device (2) being adapted to be separated from the base plate (11) with the seismic wave source (3) and the skirt (1) when the seismic source (3) is activated.