The Late Cenozoic uplift - climate change paradox

Abstract

The geologic evidence for worldwide uplift of mountain ranges in the Neogene is ambiguous. Estimates of paleoelevation vary, according to whether they are based on the characteristics of fossil floras, on the masses and grain sizes of eroded sediments, or on calculations of increased thickness of the lithosphere as a result of faulting. Detrital erosion rates can be increased both by increased relief in the drainage basin and by a change to more seasonal rainfall patterns. The geologic record provides no clear answer to the question whether uplift caused the climatic deterioration of the Neogene or whether the changing climate affected the erosion system in such a way as to create an illusion of uplift. We suggest that the spread of C 4 plants in the Late Miocene may have altered both the erosion and climate systems. These changes are responsible for the apparent contradictions between data supporting uplift and those supporting high elevations in the past. A brief historical perspectiveLyell (1830) was impressed by the marked contrast between the conditions required for deposition of the Carboniferous coals as opposed to the present climate. Convinced that the climate of the British Isles had been different in the past, he proposed that the change reflected differences in the global latitudinal distribution of land and sea, arguing that with more extensive land areas in the polar regions, the earth would become cooler, and conversely, with more land in the equatorial regions, the earth would be warmer.

History and causes of post-Laramide relief in the Rocky Mountain orogenic plateau

“…Sediment supply can be influenced indirectly by climatic control of weathering rates, vegetation distribution, and storm events (affecting sediment delivery off hillslopes). Reviews of global and regional climate change during late Cenozoic time (Zachos et al, 2001;Flower and Kennett, 1993;Hay et al, 2002) provide a basis for comparing the timing of basin filling and incision with climate change in the Rocky Mountain orogenic plateau.…”

Response to comments by John W. Russell on “Energy conservation in the Earth's crust and climate change”

“…In Hay et al (2002), such hypotheses have been classified into 11 different descriptions. Although it has so far not been reported that huge exploitation of fossil energy caused insulation seals of the earth's crust to be damaged, the correlation between the increase of terrestrial heat flow and climate change is well documented.…”

Cenozoic Climatic Record for Monsoonal Rainfall over the Indian Region

“…The authors suggest that a change has been linked to initiation or intensification of the Indian Ocean monsoons. They argued, however, that the oceanic productivity was changed in a larger region than that affected by the monsoons, and secondly the effects of mountain uplift on global climate are not well documented (Hay et al, 2002). More recent workers have tried to estimates the rate of upliftment of mountains during Cenozoic time using soil carbonates, clays and organic component in the sedimentary deposits (Garzione et al, 2004;Chamberlin, 2006).…”