The new firmware add-on for BGK1000 performes correlation and stacking of sweeps directly in the probe, cutting Vibro survey times down to a half or less.
New firmware features:
- 65 seconds sweep length (1ms)
- 4 full sweep memories downhole
- 16 full stacks of 65 seconds
- downhole stacking
- downhole correlation
- noise monitoring
- fast quality control
The new downhole correlation and stacking feature is available as add-on to new and existing BGK1000 systems.
BGK1000 did an excellent VSP-Job for the Danakil Potash Project in the north of Ethiopia. Nearly 100 m below sea level Danakil Depression is one of the deepest regions of Africa, bearing million tonnes deposits of potash.
Clemens himself lead the survey to make sure that BGK1000 works together with international seismic survey equipment, crews, and drilling and logging companies. Under very unstable borehole conditions, two nightshifts were filled with a lot of VSP-records, gathered from different vib-positions. The BGK1000 probe worked well in 400 m deep wells, filled with saturated potassium salt brine. The same sweeps and the same vib trucks were used as in the surface seismic survey. Each data record from the probe was correlated with the reference sweep of the vibrator and stored in SEG-2 format. The recording system (BGK1000 Trigger Unit and Laptop) was located in vib encoder truck and was connected to the vib encoder system (Force two). The vib encoder truck and the TerraTec winch were standing close together. The Danakil Depression is among the hottest place on earth in terms of year-round average temperatures. It is also one of the lowest places on the planet, and there is no rain for most of the year. (Wikipedia).
BGK1000 is entering Asia!
Data example from correlated shear wave sweeps under severe powerline noise surrounding. Sampling rate 1 ms, sweep length 20 s.
Left trace P-Wave, right trace S-Wave
Complete absence of powerline noise 50 Hz, 150 Hz, 16.66 Hz.
The two surveys were conducted in Switzerland under difficult environmental conditions in depths up to 720 m. The client appreciated especially the excellent noise reduction of the system, no 50 Hz powerline noise was detected.
The probe was rented for 2 missions, Clemens himself has been overseeing the first survey to train the client in the device handling.