Dataset Information
Upper Mantle Seismic Structure beneath the Northern Transantarctic Mountains from Regional P- and S-wave Tomography
Data DOI:
Cite as
Hansen, S. (2017) "Upper Mantle Seismic Structure beneath the Northern Transantarctic Mountains from Regional P- and S-wave Tomography" U.S. Antarctic Program (USAP) Data Center. doi:
AMD - DIF Record(s)
Stretching ~3,500 km across Antarctica, with peak elevations up to 4,500 m, the Transantarctic Mountains (TAMs) are the largest non-compressional mountain range on Earth and represent a tectonic boundary between the East Antarctica (EA) craton and the West Antarctic Rift System. The origin and uplift mechanism associated with the TAMs is controversial, and multiple models have been proposed. Seismic investigations of the TAMs' subsurface structure can provide key constraints to help evaluate these models, but previous studies have been primarily focused only on the central TAMs near Ross Island. Using data from the new 15-station Transantarctic Mountain Northern Network as well as data from several smaller networks, this study investigates the upper mantle velocity structure beneath a previously unexplored portion of the northern TAMs through regional body wave tomography. Relative travel-times were calculated for 11,182 P-wave and 8,285 S-wave arrivals from 790 and 581 Mw ≥ 5.5 events, respectively, using multi-channel cross correlation, and these data were then inverted for models of the upper mantle seismic structure. Resulting P- and S-wave tomography images reveal two focused low velocity anomalies beneath Ross Island (RI; δVP ≈ -2.0%; δVS ≈ -1.5% to -4.0%) and Terra Nova Bay (TNB; δVP ≈ -1.5% to -2.0%; δVS ≈ -1.0% to -4.0%) that extend to depths of ~200 and ~150 km, respectively. The RI and TNB slow anomalies also extend ~50-100 km laterally beneath the TAMs front and sharply abut fast velocities beneath the EA craton (δVP ≈ 0.5% to 2%; δVS ≈ 1.5% to 4.0%). A low velocity region (δVP ≈ -1.5%), centered at ~150 km depth beneath the Terror Rift (TR) and primarily constrained within the Victoria Land Basin, connects the RI and TNB anomalies. The focused low velocities are interpreted as regions of partial melt and buoyancy-driven upwelling, connected by a broad region of slow (presumably warm) upper mantle associated with Cenozoic extension along the TR. Dynamic topography estimates based on the imaged S-wave velocity perturbations are consistent with observed surface topography in the central and northern TAMs, thereby providing support for uplift models that advocate for thermal loading and a flexural origin for the mountain range.
Date Created:
USAP-DC (current)
Spatial Extent(s)
West: 153.327, East: 165.120012, South: -76.237352, North: -73.032547
  1. Brenn, G.R., S.E. Hansen, and Y. Park (2017), Variable thermal loading and flexural uplift along the Transantarctic Mountains, Antarctica, Geology, doi:10.1130/G38784.1. (doi:10.1130/G38784.1)
Supplemental Docs
Data Files
39.7 kB

MD5 Checksum: 5944f80dd5ba6f75329f9ddc6b4338b4 File Type: Adobe Portable Document Format (PDF)

808.0 kB

MD5 Checksum: bdd1baeea9a788acdf8df659b1738787 File Type: Text File; MatLab

2.6 kB

MD5 Checksum: 82c4161ab379762c4054e77da43b39ea File Type: Readme Text File

807.5 kB

MD5 Checksum: ed7e9d1e619623e4d9477d57eaef6834 File Type: Text File; MatLab

3.0 kB

MD5 Checksum: c48e4c592c0630f8b14f657af0722497 File Type: MatLab

3.0 kB

MD5 Checksum: c21e2eb762664320e1220977d44b2334 File Type: MatLab

This dataset has been downloaded 7 times since March 2017 (based on unique date-IP combinations)