Results 41 to 50 of about 3,442,186 (236)
Integrated bio- and cyclostratigraphy of Middle Triassic (Anisian) ramp deposits, NW Bulgaria
Geologica Carpathica, 2019 A cyclostratigraphic interpretation of peritidal to shallow-marine ramp deposits of the early Middle Triassic (Anisian) Opletnya Member exposed in outcrops along the Iskar River gorge, NW Bulgaria, is presented.
Ajdanlijsky George +2 more
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Exo-Milankovitch Cycles. I. Orbits and Rotation States [PDF]
The Astronomical Journal, 2018 Abstract The obliquity of the Earth, which controls our seasons, varies by only ∼2.°5 over ∼40,000 years, and its eccentricity varies by only ∼0.05 over 100,000 years. Nonetheless, these small variations influence Earth’s ice ages. For exoplanets, however, variations can be significantly larger.
Deitrick, Russell +5 more
openaire +4 more sources
The Astronomical Pulse of Global Extinction Events
The Scientific World Journal, 2006 The linkage between astronomical cycles and the periodicity of mass extinctions is reviewed and discussed. In particular, the apparent 26 million year cycle of global extinctions may be related to the motion of the solar system around the galaxy ...
David F.V. Lewis, Jean-Lou C.M. Dorne
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Pacing of Paleozoic macroevolutionary rates by Milankovitch grand cycles [PDF]
Proceedings of the National Academy of Sciences, 2018 SignificanceThere has been long-standing debate about the relative roles of intrinsic biotic interactions vs. extrinsic environmental factors as drivers of biodiversity change. Here, we show that, relatively early in the history of complex life, Milankovitch “grand cycles” associated with astronomical rhythms explain between 9 and 16% of variation in ...
James S. Crampton +5 more
openaire +4 more sources
Petroleum Exploration and Development, 2018 Taking organic-rich shale in the first member of Cretaceous Qingshankou Formation in the Gulong Sag, northern Songliao Basin as an example, this study examined the lithofacies classification, petrological characteristics, pore size distribution and their
Bo LIU +6 more
doaj +1 more source
The Effect of Milankovitch Variations in Insolation on Equatorial Seasonality [PDF]
, 2010 Although the sun crosses the equator 2 times per year at the equinoxes, at times in the past the equatorial insolation has had only one maximum and one minimum throughout the seasonal cycle because of Milankovitch orbital variations.
Ashkenazy, Yosef +3 more
core +2 more sources
Global and Planetary Change, 2020 The Oceanic Anoxic Event 2 (OAE2, ca. 94.6 Ma) is one of the major perturbations in the global carbon cycle during the Phanerozoic. Stable carbon isotopes (δ13C) from marine and continental sedimentary environments document this carbon cycle perturbation
S. Boulila +6 more
semanticscholar +1 more source
Quaternary chronostratigraphy - a review [PDF]
Bulletin of the Geological Society of Finland, 1992 Quaternary development is characterized by strong climatic fluctuations associated with repeated glacier expansions. Consequently the Quaternary chronostratigraphy is largely based on the dating of climatic fluctuations which have led to large-scale ...
M. Eronen
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Simulating late Pliocene northern hemisphere climate with the LLN 2-D model
, 1998 Deep-sea sediment records suggest Northern Hemisphere glaciation intensified at approximately 2.75 Ma. In this paper we simulate the fluctuations of the late Pliocene Northern Hemisphere ice-sheets volume using the LLN 2-D model, forced by the ...
Li, XS +19 more
core +1 more source
Geochemistry, Geophysics, Geosystems, 2020 The existence, or not, of periodicities in abyssal hill morphology has been vigorously debated in recent publications, and some have hypothesized that such periodicities are evidence of the impact of Milankovitch cycle‐caused sea level fluctuations on ...
John A. Goff
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