Abstract: A data acquisition and transport system including a plurality of array terminals, each array terminal having a plurality of geophones delivering analog signals thereto, the analog signals being digitized to 1-bit and temporarily stored, and on demand, transmitted downline to a recording station, as a train of 1-bit pulses. The array terminals have two identical ports into which cable segments of two conductor digital transmission channels can be plugged. Means are provided in the recording station to place a DC potential between the two terminals of the digital transmission channel. In the array terminals means are provided for identifying which of the two identical ports is the one which receives the DC potential, which is identified as the downline port. On receiving a DC potential at the downline port, a corresponding DC potential is transmitted through the upline port to the next array terminal and so on.

Abstract: A system and method for carrying out seismic operations with low energy sources, which involves operating the source at spaced points along a seismic spread, the source points are spaced far enough apart so that their seismic waves originate at different points and travel by different paths to the geophones. The geophone outputs cannot be time stacked. The geophone signals are amplified at constant gain and digitized to 1 bit. If the low energy source is a vibratory source, the 1 bit signals are correlated with a 1 bit version of the sweep signal. The resulting correlograms are digitized to 1 bit and C.D.P. stacked and displayed. If the low energy source is impulsive, the 1 bit amplified signals are C.D.P. stacked and displayed. In C.D.P. stacking, the determination of optimum velocity can be carried out by 1 bit processing.

Abstract: A simplified cable system for use in gathering S analog signals into each of T array terminals (AT), spaced apart a distance D, where the analog signals are amplified, digitized, stored and, on command, transmitted as trains of digital bits along a digital conductor pair in the cable system, to successive ATs downline, to a recording unit. In the optimum embodiment, the cables are all identical, are plugged into each of 2 ports, or receptacles, in each AT. The cables are D/2 long, have S/2 conductor pairs, and S/2 takeouts spaced D/S apart, each takeout connected to a different conductor pair. Each cable contains at least one digital conductor pair. Two cables in series connect between adjacent ATs. The plugs joining one cable to the next, connect only the digital conductor through from cable to cable, while the analog conductor pairs are dead ended at the joining plugs.