scholarly journals Glacial isostatic adjustment and the anomalous tide gauge record of eastern North America

Nature ◽  
1996 ◽  
Vol 379 (6568) ◽  
pp. 848-848
Author(s):  
James L. Davis ◽  
Jerry X. Mitrovica
1992 ◽  
Vol 29 (11) ◽  
pp. 2418-2425 ◽  
Author(s):  
A. Mark Tushingham

Churchill, Manitoba, is located near the centre of postglacial uplift caused by the Earth's recovery from the melting of the Laurentide Ice Sheet. The value of present-day uplift at Churchill has important implications in the study of postglacial uplift in that it can aid in constraining the thickness of the ice sheet and the rheology of the Earth. The tide-gauge record at Churchill since 1940 is examined, along with nearby Holocene relative sea-level data, geodetic measurements, and recent absolute gravimetry measurements, and a present-day rate of uplift of 8–9 mm/a is estimated. Glacial isostatic adjustment models yield similar estimates for the rate of uplift at Churchill. The effects of the tide-gauge record of the diversion of the Churchill River during the mid-1970's are discussed.


2008 ◽  
Vol 46 (3-5) ◽  
pp. 144-154 ◽  
Author(s):  
Wouter van der Wal ◽  
Patrick Wu ◽  
Michael G. Sideris ◽  
C.K. Shum

2011 ◽  
Vol 38 (24) ◽  
pp. n/a-n/a ◽  
Author(s):  
S. Mazzotti ◽  
A. Lambert ◽  
J. Henton ◽  
T. S. James ◽  
N. Courtier

2018 ◽  
Vol 193 ◽  
pp. 288-311 ◽  
Author(s):  
Maryam Yousefi ◽  
Glenn A. Milne ◽  
Ryan Love ◽  
Lev Tarasov

2020 ◽  
Vol 47 (10) ◽  
Author(s):  
Tanghua Li ◽  
Patrick Wu ◽  
Hansheng Wang ◽  
Holger Steffen ◽  
Nicole S. Khan ◽  
...  

2020 ◽  
Author(s):  
Tanghua Li ◽  
Nicole Khan ◽  
Simon Engelhart ◽  
Alisa Baranskaya ◽  
Peltier William ◽  
...  

<p>The Canadian landmass of North America and the Russian Arctic were covered by large ice sheets during the Last Glacial Maximum, and have been key areas for Glacial Isostatic Adjustment (GIA) studies. Previous GIA studies have applied 1D models of Earth’s interior viscoelastic structure; however, seismic tomography, field geology and recent studies reveal the potential importance of 3D models of this structure. Here, using the latest quality-controlled deglacial sea-level databases from North America and the Russian Arctic, we investigate the effects of 3D structure on GIA predictions. We explore scaling factors in the upper mantle (<em>β<sub>UM</sub></em>) and lower mantle (<em>β<sub>LM</sub></em>) and the 1D background viscosity model (<em>η<sub>o</sub></em>) with predictions of of the ICE-6G_C (VM5a) glaciation/deglaciation model of Peltier et al (2015, JGR) in these two regions, and compare with the best fit 3D viscosity structures.</p><p>We compute gravitationally self-consistent relative sea-level histories with time dependent coastlines and rotational feedback using both the Normal Mode Method and Coupled Laplace-Finite Element Method. A subset of 3D GIA models is found that can fit the deglacial sea-level databases for both regions. These databases cover both the near and intermediate field regions. However, North America and Russian Arctic prefer different 3D structures (i.e., combinations of (<em>η<sub>o</sub>, β<sub>UM</sub>, β<sub>LM</sub></em>)) to provide the best fits. The Russian Arctic database prefers a softer background viscosity model (<em>η<sub>o</sub></em>), but larger scaling factors (<em>β<sub>UM</sub>, β<sub>LM</sub></em>) than those preferred by the North America database.</p><p>Outstanding issues include the uncertainty of the history of local glaciation history. For example, preliminary modifications of the ice model in Russian Arctic reveal that the misfits of 1D models can be significantly reduced, but still fit less well than the best fit 3D GIA model.An additional issue concerns the extent to which the 3D models are able to improve both fits in North America and Russian Arctic when compared with 1D internal structure (ICE-6G_C VM5a & ICE-7G VM7), will be assessed in a preliminary fashion.</p>


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