Robert H. Dott, Jr., 1992. "Chapter 4: T. C. Chamberlin’s hypothesis of diastrophic control of worldwide changes of sea level: A precursor of sequence stratigraphy", Eustasy: The Historical Ups and Downs of a Major Geological Concept, Robert H. Dott, Jr.
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T. C. Chamberlin’s 1898 diastrophic (tectonic) control paper was a short editorial-like response to a questionnaire about geologic time divisions; the more famous and even shorter 1909 paper restated the primacy of diastrophic control of worldwide unconformities as a basis for correlation. This hypothesis derived from Chamberlin’s beloved planetesimal theory, which postulated a gravitationally shrinking globe. The earth was considered entirely solid with isostatic equilibration being effected by periodic vertical adjustments between deep, wedge-shaped blocks. During early planetesimal accretion, minor heterogeneities augmented by weathering processes led to denser, lower oceanic and lighter, higher continental wedges. Shrinkage-induced global stress caused spasmodic sinking of the oceanic wedges, which produced elevation (or lesser subsidence) of continental ones, thus regression. During subsequent, longer diastrophic quiescence, erosion reduced continents and extended the “circumcontinental submarine terrace” (shelf) by sedimentation. Areas elevated above their isostatic equilibrium level would slowly settle back to equilibrium. This crustal sinking, coupled with sedimentation-induced displacement of sea water, now caused transgression. The oscillations of sea level would also dramatically affect organic evolution and produce important climatic effects as well. During continental emergence, weathering would consume CO2, causing cooling, but during transgressions, CO2 would accumulate in the atmosphere to cause greenhouse warming. Such climatic changes should accentuate the effects of global diastrophism as the “ulterior basis of time divisions.”
Although Chamberlin did not employ the term eustasy, he presented an appealing and influential mechanism, which showed striking resemblances to Eduard Suess’ concepts of global contraction and periodic eustatic changes published ten years earlier. Chamberlin’s hypothesis of repetitive, synchronous worldwide changes of sea level with resulting universal unconformities punctuating the global stratigraphic record— “correlated pulsations”—was to have a profound effect upon many subsequent workers, especially in North America, and was an important precursor of modern sequence stratigraphy.