Constraints on past plate and mantle motion from new ages for the Hawaiian-Emperor Seamount Chain


Contact
Wilfried.Jokat [ at ] awi.de

Abstract

Estimates of the relative motion between the Hawaiian and Louisville hot spots have consequences for understanding the role and character of deep Pacific-mantle return flow. The relative motion between these primary hot spots can be inferred by comparing the age records for their seamount trails. We report 40Ar/39Ar ages for 18 lavas from 10 seamounts along the Hawaiian-Emperor Seamount Chain (HESC), showing that volcanism started in the sharp portion of the Hawaiian-Emperor Bend (HEB) at ≥47.5 Ma and continued for ≥5 Myr. The slope of the along-track distance from the currently active Hawaiian hot spot plotted versus age is constant (57 ± 2 km/Myr) between ∼57 and 25 Ma in the central ∼1900 km of the seamount chain, including the HEB. This model predicts an age for the oldest Emperor Seamounts that matches published ages, implying that a linear age-distance relationship might extend back to at least 82 Ma. In contrast, Hawaiian age progression was much faster since at least ∼15 Ma and possibly as early as ∼27 Ma. Linear age-distance relations for the Hawaii-Emperor and Louisville seamount chains predict ∼300 km overall hot spot relative motion between 80 and 47.5 Ma, in broad agreement with numerical models of plumes in a convecting mantle, and paleomagnetic data. We show that a change in hot spot relative motion may also have occurred between ∼55 Ma and ∼50 Ma. We interpret this change in hot spot motion as evidence that the HEB reflects a combination of hot spot and plate motion changes driven by the same plate/mantle reorganization.



Item Type
Article
Authors
Divisions
Primary Division
Programs
Primary Topic
Peer revision
ISI/Scopus peer-reviewed
Publication Status
Published
Eprint ID
35519
DOI 10.1002/ggge.20267

Cite as
O'Connor, J. M. , Steinberger, B. , Regelous, M. , Koppers, A. A. , Wijbrans, J. R. , Haase, K. M. , Stoffers, P. , Jokat, W. and Garbe-Schönberg, D. (2013): Constraints on past plate and mantle motion from new ages for the Hawaiian-Emperor Seamount Chain , Geochemistry, Geophysics, Geosystems, 14 (10), pp. 4564-4584 . doi: 10.1002/ggge.20267


Download
[img]
Preview
PDF
OConnor-2013-g3-HawaiiSmtAges.pdf

Download (1MB) | Preview
Cite this document as:

Share


Citation

Research Platforms
N/A

Campaigns


Actions
Edit Item Edit Item