Client Enterprise Oil / SHELL – (Click here to see the brochure)

The block is located within a thrust belt zone in NW Greece and conventional seismic failed to provide any information due to bad seismic energy penetration problems. The upper layers consisted of Karstified weathered limestone. The region is mountainous.

Scope of the survey was to:

  • Map the evaporites
  • Obtain an accurate velocity model to reprocess the 2D seismic sections
  • Obtain a 3D geological model
  • Locate possible targets of hydrocarbon potential

 

Passive seismic case study

In the illustation below we present the waveforms of a microearthquake recorded at 26 stations of the installed network. Note the arrivals of P and S waves.

Passive seismic case study

Passive seismic case study

Passive seismic case study

After obtaining the 3D Vp, and Poisson’s structure of the whole of the block, and setting specific velocity and Poisson’s value limits we can isolate and map in 3D particular formations. Below we present an example of evaporites mapping.

Passive seismic case study

Knowing that the limestones in the region have Vp values>5.6Km/s and isolating from the 3D velocity volume all formations with Vp values greater than 5.6 we were able to map the basement bedrock as it is depicted in the figure below.

Passive seismic case study

The obtained PST data were also in agreement with gravity data

Passive seismic case study

The obtained PST data can also be presented in the form of 3D animated videos.