TOPAS subbottom profiler (SBP) data acquired during research voyage TAN2006 with R/V Tangaroa (2020)

Overview

Raw and processed TOPAS subbottom profiler (SBP) dataset acquired during research voyage TAN2006 with R/V Tangaroa in 2020.

Acquisition parameter

Kongsberg Maritime TOPAS PS 18 Parametric Sub-Bottom Profiler

Pulse form: Chirp (linear frequency-modulated)Chirp frequency: 2–6 kHzChirp length: 20 msSample rate: 40 kHzGain (receiver): 0 dBHigh-pass filter: 1 kHzHeave/Roll/Pitch stabilisation

SEG-Y file metadata

EBCDIC Text Header EncodingBig Endian byte orderSample Format: IEEE Float (32 bit)Sample Interval (uS) : 25 (raw), 50 (processed)

Processing workflow

The processing is applied using the "pseudo-3D-interpolation" workflow available on GitHub and archived via Zenodo.

(if required) MERGED individual line parts

CRS (projected): EPSG:32760

REPROJECT (bytes:73,77)

(if required) DELRT FIX

(if required) PAD DELRT

STATIC CORRECTION:amp (byte:103) with SCALAR (byte:233) -> SEAFLOOR (byte:237) with SCALAR (byte:233)

TIDE COMPENSATION

MISTIE

DESPIKE

RESAMPLE (dt=0.05 ms)

GAIN (tpow=1.5 scale=1e-0.5)

ENVELOPE

GAIN (linear=1,3)

References

Pecher, I.A.; Hillman, J.I.T.; Davy, B.W.; Gorman, A.R.; Woelz, S.; Andrew, D.; Boettger, L.; Dalbeth, A.; Gerring, P.; Hoffman, J.; Macnaughton, M.; Oluwunmi, P.; Quinn, W.; Shorrock, A.; Tankersley, M. 2022 ‘Geologic Champagne’ voyage report R/V Tangaroa TAN2006: 26 June – 17 July 2020, Wellington–Wellington. Lower Hutt, N.Z.: GNS Science. GNS Science report 2021/26. 65 p.; doi: 10.21420/GT27-A456