It has been proposed that hot spot tracks are caused by moving rigid plates above relatively stationary hot spots. However, the fixity of hot spots remains under debate. Here, we perform 3‐D very high resolution (<25 km laterally) global mantle convection models with realistic convection vigor to investigate the lateral motion of mantle plumes. We find that the lateral motion of plumes beneath the Pacific plate is statistically similar to that beneath the Indo‐Atlantic plates. In the past 80 Ma, the majority (>90%) of plumes move laterally with an average speed of 0–20 mm/year under the no‐net‐rotation reference frame, and there are a small portion (~10–20%) of plumes whose lateral motion is less than 5 mm/year. The geodynamic modeling results are statistically in a good agreement with the hot spot motions in the last 5 Ma estimated from observation‐based kinematic models. Our results suggest a small‐to‐moderate (0–20 mm/year) lateral motion of most plume‐induced hot spots.
The Global Moving Hotspot Reference Frame (GMHRF) has been claimed to fit hot spot tracks better than the fixed hot spot approximation mainly because the GMHRF predicts ≈1,000 km southward motion through the mantle of the Hawaiian mantle plume over the past 80 Ma. As the GMHRF is determined by starting at present and calculating backward in time, it should be most accurate and reliable for the recent geologic past. Here we compare the fit of the GMHRF and of fixed hot spots to the observed trends of young tracks of hot spots. Surprisingly, we find that the GMHRF fits the data significantly worse (
- NSF-PAR ID:
- 10362211
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 46
- Issue:
- 14
- ISSN:
- 0094-8276
- Page Range / eLocation ID:
- p. 8031-8038
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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