Deliverables include PSTM, PSDM, FloatSeis™ velocities, marine gravity and magnetic data.

  • Provide high quality deep depth imaged exploration seismic data integrated with gravity and magnetic data

  • Cross wells and potential fields anomalies

  • Reveal the major elements of the Earth crust architecture

  • Reveal presence of deformations indicative of basement’s extension or compression

  • Deep investigation of the crystalline basement

The objectives of the project were as follows:

Geological Objectives

FloatSeis™ line running through Lesser Antilles was a part of a Caribbean Basin Program aimed at deep investigation of the crystalline basement, revealing the major elements of the Earth crust architecture. 2D towed seismic streamer data was acquired with a 12 km streamer and 7060 cu. inch air gun array. Dominance of diffractions and ray bending associated with steep dips and irregular bedding reduced veracity of CDP velocity analysis causing CDP velocity model being “patchy” and non-geological. Presence of high-velocity igneous layers caused problems with energy penetration because of the large seismic impedance contrast. Thus, the main goals of seismic imaging and interpretation became challenging. Long offset data (30km+) recorded with help of FloatSeis™ acquisition technique and asserted into the processing routine helped to create geologically consistent velocity model along the 2D CDP seismic line. Pre-stack depth migration with an alternative FloatSeis™ long-offset velocity model considerably enhanced wavefield quality in the challenging areas with complex geological structures. Therefore, the clarity of the seismic image, quality of reflecting horizons tracing and data interpretation were uplifted.

2D CDP seismic streamer acquisition parameters:

  • Source — 7060 cu. inch; 2000 psi

  • Streamer — 12,000m

  • Recording — 50m pop, 18 sec records

GWL FloatSeis™ super-long offset acquisition parameters:

  • Recording units interval – 6 km

  • Recorded offsets – 30 km+

  • Continuous recording

Program time frame: 2016

Lesser Antilles FS line was aimed at testing GWL FloatSeis™ technology capabilities in a complex geological environment.  The simultaneously acquired 295 km of long-offset 2D seismic streamer data together with GWL FloatSeis™ super-long offset data helped to reveal add value that GWL FloatSeis™ technology is able to bring to the market.

Survey Information