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Title: Evaluating the Relationship Between the Area and Latitude of Large Igneous Provinces and Earth's Long-Term Climate State
One of the hypothesized effects of large igneous provinces (LIPs) is planetary cooling on million-year timescales associated with enhanced silicate weathering of freshly emplaced basalt. This study combines reconstructions of the original surface extent and emplacement ages of LIPs, a paleogeographic model, and a parameterization of LIP erosion to estimate LIP area in all latitudinal bands through the Phanerozoic. This analysis reveals no significant correlation between total LIP area, nor LIP area in the tropics, and the extent of continental ice sheets. The largest peaks in tropical LIP area are at times of non-glacial climate. These results suggest that changes in planetary weatherability associated with LIPs are not the fundamental control on whether Earth is in a glacial or non-glacial climate, although they could provide a secondary modulating effect in conjunction with other processes.  more » « less
Award ID(s):
1925990
NSF-PAR ID:
10281977
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Geophysical monograph
Volume:
255
ISSN:
2328-8779
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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