Auxiliary Material for
Compressional and shear-wave velocity structure of the continent-ocean transition zone at the
eastern Grand Banks, Newfoundland
Drew R. Eddy and Harm J. A. Van Avendonk
(University of Texas Institute for Geophysics, Jackson School of Geosciences, The University of
Texas at Austin, Austin, Texas, USA)
Donna J. Shillington
(Lamont-Doherty Geological Observatory of Columbia University, Palisades, New York, USA)
Geophysical Research Letters, 2013
Introduction
The appendix describes a test of three bulk Vp / Vs ratios in the Newfoundland Basin continentocean transition zone (COT) using text (text01) and a figure (fs01). The text, text01, describes
the impact of changing the bulk vpvs ratio on shear-wave travel-time misfits, and the resulting
geological implications for our interpretations of the Newfoundland COT. Figure fs01displays
picked and calculated shear waves and corresponding raypaths through the tested bulk models.
The appendix also includes a table (ts01) with ranges of Vp and Vp / Vs values experimentally
determined for common COT lithologies. Table ts01 corresponds to velocities plotted in Figure
4. Lastly, the appendix has supplementary images (fs02-fs05) of receiver gathers with interpreted
refractions and reflections for OBS 08 (fs02), 12 (fs03), 19 (fs04), and 23 (fs05).
1. text01 Text describing bulk Vp / Vs ratio tests and geological implications for the COT
2. ts01.txt Compressional and shear wave velocities of common COT lithologies.
2.1. Column “Rock Type”, common lithologies found in magma-poor COTs.
2.2. Column “Vp”, range of compressional velocities (in km/s) for rock types in Column 1.1.
2.3. Column “Vp/Vs”, range of Vp / Vs ratios for rock types in Column 1.1.
2.4. Column “Reference”, reference from which published values for Column 1.2 and 1.3
were described.
3. fs01 Three bulk Vp / Vs ratios and their effect on shear-wave travel-time misfits for OBS
15, 17, and 19 in the Newfoundland COT. Blue and red lines are picked and caluclated
shear-wave travel-time curves, respectively. Reduction velocity = 4.0 km/s. RMS = rootmean-squared misfit. a) – Vp / Vs = 1.65; b) – Vp / Vs = 1.77; c) – Vp / Vs = 1.87.
4. fs02 A portion of the receiver gather for OBS 08. Labeled are arrivals of a compressional
refraction (P4) and a shear wave (S).
5. fs03 A portion of the receiver gather for OBS 12. Labeled are arrivals of compressional
refractions and reflections (P1-P4, R1-R3). Also labeled are arrivals of the direct wave in
water (Water) and a shear wave (S).
6. fs04 A portion of the receiver gather for OBS 19. Labeled are arrivals of compressional
refractions (P2, P4), compressional reflections (R3), and a shear wave (S).
7. fs05 A portion of the receiver gather for OBS 23. Labeled are arrivals of compressional
refractions and reflections (P1-P4, R1-R3). Also labeled are arrivals of the direct wave in
water (Water) and shear waves (S).