Tag:Seismic
After the surveyor cut his line, a ‘bridging crew’ would follow along behind and cut smaller trees to form a walkway, or bridge. Typically three poles wide and nailed together, it made walking the lines considerably easier for the rest of us and in most cases kept our feet dry also. It also meant that relatively few people were actually tromping across the jungle floor.
Actually, the shot below is of a pretty shoddy job. If we’d done it properly, as we did most of the time, there wouldn’t have been any blow-out. Here, a large part of the energy of the charge is moving upwards as the shot hole blows out and the noise generated when the dirt falls back to the ground also degrades the signal. But when a shot goes well, there’s nothing to photograph.
When I first went to Libya in 1984 I was an ‘Assistant Seismologist’. My job function was to determine the static corrections needed to apply to the seismic data so it all made sense in the processing cycle. To do this we had a couple of Mayhew 1000 drilling rigs mounted on Belgian MOL trucks. They’d go out to the location we directed and drill typically a 10 cm diameter hole to a depth of up to 100 meters. I’d […]
