ABSTRACT FROM:Age Dating and the Orbital Theory of the Ice Ages: Developemtn of a High-Resolution 0 to 300,000-year Chronostratigraphy

Using the Concept of "orbit tuning," a continuous, high-resolution deep-sea chronostratigraphy has been developed spanning the last 300,000 yr. The chronology is developed using a stacked oxygen-isotope stratigraphy and four different orbital tuning approaches, each of which is based upon a different assumption concerning the response of the orbital signal recorded in the data. Each approach yields a seperate chronology. The error measured by the standard deviation about the average of these four results (which represent the "best" chronology) has an average magnitude of only 2500 yr. This small value indicates that the chronology produced is insensitive to the specific orbital tuning technique used. Excellent convergence between chronologies developed using each of five different paleoclimatological indicators (from a single core) is also obtained. the resultant chronology is also insensitive to the specific indicator used. The error associated with each tuning approach is estimated independently and propagated through to the average result. The resulting erorr estimate is independent of that associated with the degree of convergence and ahs an average magnitude of 3500 yr, in excellent agreement with the 2500-yr estimate. Transfer of the final chronology to the stacked record leads to an estimated error of ± 1500 yr. Thus the final chronology has an average error of ± 5000 yr. © 1987 University of Washington.

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