The tectonic fabric of the ocean basins

Full description

This data collection is associated with the publication: Matthews, K. J., Müller, R. D., Wessel, P., & Whittaker, J. M. (2011). The tectonic fabric of the ocean basins. Journal of Geophysical Research: Solid Earth, 116(B12). doi: 10.1029/2011JB008413

Publication Abstract

We present a global community data set of fracture zones (FZs), discordant zones, propagating ridges, V-shaped structures and extinct ridges, digitized from vertical gravity gradient (VGG) maps. We use a new semi-automatic FZ tracking program to test the precision of our hand-digitized traces and find a Mean Absolute Deviation of less than 3.4 km from the raw VGG minima that most clearly delineate each feature, and less than 5.4 km from the FZ location predicted by fitting model profiles to the VGG data that represent the morphology of the individual FZs. These offsets are small considering gravity data only provide an approximation for the underlying basement morphology. We further investigate the origin of non-FZ seafloor fabric by combining published abyssal hill heights computed from gravity anomalies with global half-spreading rates. A residual abyssal hill height grid, with spreading rate effects removed, combined with our interpreted tectonic fabric reveals several types of seafloor fabric distinct from typical abyssal hills. Where discordant zones do not overprint abyssal hill signals, residual abyssal hill height anomalies correspond to seafloor that accreted near mantle thermal anomalies or zones of melt-depletion. Our analysis reveals several areas where residual abyssal hill height anomalies reflect pseudo-faults and extinct ridges associated with ridge propagation and/or microplate formation in the southern Pacific Ocean.

Authors and Institutions

Kara J. Matthews - EarthByte Research Group, School of Geosciences, The University of Sydney

Joanne M. Whittaker - EarthByte Research Group, School of Geosciences, The University of Sydney

R. Dietmar Müller - EarthByte Research Group, School of Geosciences, The University of Sydney

Paul Wessel - University of Hawaii at Manoa

Overview of Resources Contained

This dataset contains hand-digitised traces of fracture zones, discordant zones, V-shaped structures, unclassified V-anomalies, pseudofaults and extinct ridges. Features were digitised in Google Earth from Sandwell and Smith's (2009) v16.1 vertical gravity gradient data. Apart from the Bay of Biscay ridge and the Sonne ridge in the Cuvier Abyssal Plain, all features were traced along their vertical gravity gradient minima.

List of Resources

Note: For details on the files included in this data collection, see “Description_of_Resources.txt”.

Note: For information on file formats and what programs to use to interact with various file formats, see “File_Formats_and_Recommended_Programs.txt”.

• Discordant zones (.gpml, .kml, .txt, .shp, total 6 MB)
• Extinct ridges (.gpml, .kml, .txt, .shp, total 1.1 MB)
• Fracture zones (.gpml, .kml, .txt, .shp, total 30.5 MB)
• Fracture zones, less certainty (.gpml, .kml, .txt, .shp, total 1.2 MB)
• Tectonic fabric map (.jpg, 2.6 MB)
• Propagating ridges (.gpml, .kml, .txt, .shp, total 283 KB)
• Pseudofaults (.gpml, .kml, .txt, .shp, total 164 KB)
• Table 1 from Matthews et al. (2011) (.pdf, 82 KB)
• Unclassified V-anomalies (.gpml, .kml, .txt, .shp, total 1.1 MB)
• V-shaped structures (.gpml, .kml, .txt, .shp, total 135 KB)

For more information on this data collection, and links to other datasets from the EarthByte Research Group please visit Earthbyte

For more information about using GPlates, including tutorials and a user manual please visit GPlates or Earthbyte