Mantle transition zone beneath central-eastern Greenland: Possible evidence for a deep tectosphere from receiver functions

Mantle transition zone beneath central-eastern Greenland: Possible evidence for a deep... We investigate the mantle of central-eastern Greenland by using recordings with data from 24 local broad-band seismograph stations. We apply P wave receiver function technique and evaluate the difference in the arrival times of seismic phases that are formed by P to SV mode conversion at the 410-km and 660-km seismic discontinuities. These boundaries mark the top and bottom of the mantle transition zone (MTZ). The difference in the arrival time of the phases from the 410-km and 660-km discontinuities is sensitive to the thickness of the MTZ and relatively insensitive to volumetric velocity anomalies above the 410-km discontinuity. Near the east coast of Greenland in the region of the Skaergaard basalt intrusions we find two regions where the differential time is reduced by more than 2 s. The 410-km discontinuity in these regions is depressed by more than 20 km. The depression may be explained by a temperature elevation of ~150 °C. We hypothesize that the basaltic intrusions and the temperature anomalies at a depth of ~400 km are, at least partly, effects of the passage of Greenland over the Iceland hotspot at about 55 Ma. This explanation is consistent with the concept of tectosphere and implies that the upper mantle to a depth of ~400 km translates coherently with the Greenland plate. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Tectonophysics Elsevier

Mantle transition zone beneath central-eastern Greenland: Possible evidence for a deep tectosphere from receiver functions

Loading next page...
1
 
/lp/elsevier/mantle-transition-zone-beneath-central-eastern-greenland-possible-oBlqM7W2wK
Publisher
Elsevier
Copyright
Copyright © 2018 Elsevier B.V.
ISSN
0040-1951
eISSN
1879-3266
D.O.I.
10.1016/j.tecto.2018.02.008
Publisher site
See Article on Publisher Site

Abstract

We investigate the mantle of central-eastern Greenland by using recordings with data from 24 local broad-band seismograph stations. We apply P wave receiver function technique and evaluate the difference in the arrival times of seismic phases that are formed by P to SV mode conversion at the 410-km and 660-km seismic discontinuities. These boundaries mark the top and bottom of the mantle transition zone (MTZ). The difference in the arrival time of the phases from the 410-km and 660-km discontinuities is sensitive to the thickness of the MTZ and relatively insensitive to volumetric velocity anomalies above the 410-km discontinuity. Near the east coast of Greenland in the region of the Skaergaard basalt intrusions we find two regions where the differential time is reduced by more than 2 s. The 410-km discontinuity in these regions is depressed by more than 20 km. The depression may be explained by a temperature elevation of ~150 °C. We hypothesize that the basaltic intrusions and the temperature anomalies at a depth of ~400 km are, at least partly, effects of the passage of Greenland over the Iceland hotspot at about 55 Ma. This explanation is consistent with the concept of tectosphere and implies that the upper mantle to a depth of ~400 km translates coherently with the Greenland plate.

Journal

TectonophysicsElsevier

Published: Mar 20, 2018

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off