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Triton Isis User Manual

Page 125

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June 2004 Isis® Sonar User's Manual, Volume 2

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2. The following values are computed with the calibration coefficients read from the

file ISIS.CTD:

• Water temperature (degrees C)

• Pressure (psia)

• Conductivity (Siemens per meter)






Multiply Siemens per meter by 10.0 to get mmho/cm)

• Velocity of sound in water

3. If saving data in SEG-Y format, the values are saved in the first and second

channel’s binary trace header as shown in the tables, where first byte in header is
byte 0:

Table G-1. SeaBird’s CTD SEG-Y values in first channel’s binary trace header

long

ConductivityFreq

bytes 200-203

Siemens per meter *10000

long

TemperatureFreq

bytes 204-207

stored, times 10000

long

PressureFreq

bytes 208-211

stored, times 10

long

PressureTemp

bytes 212-215

stored, times 100

short

Turbidity

bytes 216-217

Turbidity sensor in volts, times 10000

Appendix G: How Isis Processes CTD Data