TECSOU
- found by echo-sounder: the depth was determined
by using an instrument that determines depth of water by measuring the time interval
between emission of a sonic or ultrasonic signal and return of its echo from the bottom.
(adapted from IHO Dictionary, S-32, 1547)
- found by side-scan-sonar: the depth was
computed from a record produced by active sonar in which fixed acoustic beams are directed
into the water perpendicularly to the direction of travel to scan the bottom and generate
a record of the bottom configuration. (adapted from IHO Dictionary, S-32, 4710)
- found by multi-beam: the depth was determined
by using a wide swath echo sounder that uses multiple beams to measure depths directly
below and transverse to the ship's track. (adapted from IHO Dictionary, S-32, 3339)
- found by diver: the depth was determined by a
person skilled in the practice of diving. (adapted from IHO Dictionary, S-32, 1422)
- found by lead-line: the depth was determined by
using a line, graduated with attached marks and fastened to a sounding lead. (adapted from
IHO Dictionary, S-32, 2698)
- swept by wire-drag: the given area was
determined to be free from navigational dangers to a certain depth by towing a buoyed wire
at the desired depth by two launches, or a least depth was identified using the same technique. (adapted
from IHO Dictionary, S-32, 5248, 6013)
- found by laser: the depth was determined by using an instrument that measures
distance by emitting timed pulses of laser light and measuring the time between emission
and reception of the reflected pulses. (adapted from IHO Dictionary, S-32, 2763)
- swept by vertical acoustic system: the given
area has been swept using a system comprised of multiple echo sounder transducers attached
to booms deployed from the survey vessel.
- found by electromagnetic sensor: the depth was
determined by using an instrument that compares electromagnetic signals. (adapted from IHO
Dictionary, S-32, 1571)
- photogrammetry: the depth was determined by
applying mathematical techniques to photographs. (adapted from IHO Dictionary, S-32, 3791)
- satellite imagery: the depth was determined by
using instruments placed aboard an artificial satellite. (adapted from IHO Dictionary,
S-32, 4509)
- found by levelling: the depth was determined
by using levelling techniques to find the elevation of the point relative to a datum.
(adapted from IHO Dictionary, S-32, 2741)
- swept by side-scan-sonar: the given area was
determined to be free from navigational dangers to a certain depth by towing a
side-scan-sonar. (adapted from IHO Dictionary, S-32, 5248, 4710) [415.2]
- computer generated: the sounding was
determined from a bottom model constructed using a computer.