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I only recently learned this and I'm sure this has already been posted: Empirical evidence for stability of the 405-kiloyear Jupiter–Venus eccentricity cycle over hundreds of millions of years "Rhythmic climate cycles of various assumed frequencies recorded in sedimentary archives are increasingly used to construct a continuous geologic timescale. However, the age range of valid theoretical orbital solutions is limited to only the past 50 million years. New U–Pb zircon dates from the Chinle Formation tied using magnetostratigraphy to the Newark–Hartford astrochronostratigraphic polarity timescale provide empirical confirmation that the unimodal 405-kiloyear orbital eccentricity cycle reliably paces Earth’s climate back to at least 215 million years ago, well back in the Late Triassic Period" Also... Milankovitch Cyclicity in the Eocene Green River Formation of Colorado and Wyoming "The Eocene Green River Formation is a classic example of cyclic lacustrine sediments. Following Bradley (1929, U.S.G.S. Prof. Paper 158-E), many descriptive studies suggested precession and eccentricity as the probable climatic forcing to produce the cyclic pattern. Here we report spectral analysis results that confirm this hypothesis. Furthermore, we have identified the presence of a surprisingly large amplitude obliquity cycle, the long-period eccentricity cycle (400 k.y.) and the long period modulators of obliquity. Spectral analyses of data from Colorado were undertaken on an outcrop section and core data using two different proxies for lake depth. "

From rocks in Colorado, evidence of a 'chaotic solar system' University of Wisconsin-Madison, February 22, 2017 http://news.wisc.edu/from-rocks-in-colorado-evidence-of-a-chaotic-solar-system/ https://www.sciencedaily.com/releases/2017/02/170222131512.htm http://www.astrobio.net/also-in-news/rocks-colorado-evidence-chaotic-solar-system/ The paper is: Ma, C., S. R. Meyers, and B. B. Sageman. Theory of chaotic orbital variations confirmed by Cretaceous geological evidence. Nature, 2017; 542 (7642): 468-470 DOI: 10.1038/nature21402 http://www.nature.com/nature/journal/v542/n7642/full/nature21402.html Related paper: Sageman, B. B., J. Rich, M. A. Arthur, G. E. Birchfield, and W. E. Dean, 1997, Evidence for Milankovitch Periodicities in Cenomanian-Turonian Lithologic and Geochemical Cycles, Western Interior U.S.A. Journal of Sedimentary Research, Section B: Stratigraphy and Global Studies Vol. 67 (1997) No. 2. (March), Pages 286-302 http://www.earth.northwestern.edu/research/sageman/PDF/97.Sageman.etal.pdf Yours, Paul H.