Planetary chaos and inverted climate phasing in the Late Triassic of Greenland.
Proc Natl Acad Sci U S A
; 119(17): e2118696119, 2022 04 26.
Article
in En
| MEDLINE
| ID: mdl-35452307
ABSTRACT
Sedimentological records provide the only accessible archive for unraveling Earth's orbital variations in the remote geological past. These variations modulate Earth's climate system and provide essential constraints on gravitational parameters used in solar system modeling. However, geologic documentation of midlatitude response to orbital climate forcing remains poorly resolved compared to that of the low-latitude tropics, especially before 50 Mya, the limit of reliable extrapolation from the present. Here, we compare the climate response to orbital variations in a Late Triassic midlatitude temperate setting in Jameson Land, East Greenland (â¼43°N paleolatitude) and the tropical low paleolatitude setting of the Newark Basin, with independent time horizons provided by common magnetostratigraphic boundaries whose timing has been corroborated by uranium-lead (U-Pb) zircon dating in correlative strata on the Colorado Plateau. An integrated cyclostratigraphic and magnetostratigraphic age model revealed long-term climate cycles with periods of 850,000 and 1,700,000 y ascribed to the MarsEarth grand orbital cycles. This indicates a 21 resonance between modulation of orbital obliquity and eccentricity variations more than 200 Mya and whose periodicities are inconsistent with astronomical solutions and indicate chaotic diffusion of the solar system. Our findings also demonstrate antiphasing in climate response between low and midlatitudes that has implications for precise global correlation of geological records.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Planets
/
Climate
Type of study:
Prognostic_studies
Country/Region as subject:
America do norte
/
Europa
Language:
En
Journal:
Proc Natl Acad Sci U S A
Year:
2022
Document type:
Article
Affiliation country:
Dinamarca