Tracing short cycles in long records: the study of inter-annual to inter-centennial climate change from long sediment records, examples from the Santa Barbara Basin

Abstract

We present a review of digital imaging techniques to obtain highest resolution colour/greyvalue time-series from geological material. From suitable sediments these methods can yield time-series with subannual resolution. They can be utilized for the detection of high-frequency (< 300 years) climate change over long periods of time. Automated laminae counting produces a high-precision stratigraphy and data on the laminae thickness. The application of the methods to drill cores from the Santa Barbara Basin demonstrates the power of the techniques in detecting rapid climate change. El Niño/Southern Oscillation cycles as well as solar and lunar cycles could be detected from both, the greyvalue and the laminae thickness time-series. Evolutionary power spectra, calculated from the colour/greyvalue time-series, reveal dramatic variations in the power and frequency of rapid climate oscillations during the Holocene.