Page 32: of Offshore Engineer Magazine (Mar/Apr 2013)

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Geology & Geophysics

Figure 1 Figure 2.illustrates how the pressure (blue) and particle The image on the left is the result of seismic velocity (red) amplitude spectra are complementary when inversion applied to conventional seismic data containing measured at the same depth and location (‘collocated’). both source and receiver ghost effects. The color scale

Periodic notches in both spectra are related to the receiver represents ‘P impedance’: the product of compressional depth and the angle of emergence of the seismic wavefeld. velocity and density. In contrast, the right image represents

As the emergence angle increases (vertical propagation the ghost-free result provided from PGS GeoSource means zero emergence angle), the notches move to higher and dual-sensor GeoStreamer technologies. Note the frequencies. improvements in resolution on the right.

BOP INSPECTION: ON DECK, ON DEMAND

With an increased emphasis on regular Blowout Preventer (BOP) inspection and maintenance, Kongsberg

Maritime’s Portable On Deck BOP Video Inspection System is the perfect tool for internal visual verification of bore, seals and components while the BOP is on the surface prior to drilling operations or during BOP repair and maintenance periods and now includes an improved Portable Surface Control pgg y Unit providing greater flexibility and control, viewing and recording of images.

??Continuous Rotate and Tilt, Zoom

Camera with inbuilt directional LEDs ??Robust Stainless Steel Centralising

Running Frame ??New, improved Portable Surface

Control Unit, providing control, viewing and recording

THE FULL PICTURE

Telephone: +44 1224 226500 [email protected] www.km.kongsberg.com/bop

OE | March 2013 oedigital.com 34 oe_PGS_rev2.indd 34 27/02/2013 13:22