Browsing by Author "Rein, B"

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    Peru margin palaeoceanography since the Last Glacial Maximum and the long-term implications for El Niño-Southern Oscillation
    (Australian Geosciences Council, 2012-08-05) Skilbeck, G; Gutierrez, D; Rein, B; Sifeddine, A; Salvatteci, R; Fink, D; Druffel, E; Sanchez-Cabeza, JA; Morgenstern, U; Murray, B; Dunbar, R
    Laminated-sediment cores from nine shelf sites along the Peru continental margin between 11◦S and 14.5◦S, reveal a 20,000 yr inter-millennial scale pattern of sediment accumulation consistent with other equatorial and south Pacific-rim indicators of long-term ENSO behaviour. Nearly 200 carbon-14 dates define 6 distinct periods during the Holocene-LGM each characterised by linear sedimentation rates that can be regionally correlated between the cores. The early (∼10–8.5 cal Kyr BP) and late (∼2.5–0cal Kyr BP) Holocene, and early Deglaciation (15.5–20Kyr BP) were periods of relatively rapid accumulation (∼80 and 100+ cm/ka), with thin, rapidly deposited laminae, whereas from ∼4.5 to ∼2.5 cal Kyr BP sediments accumulated at ∼20 cm/ka. The middle Holocene (∼8.5 to 4.5 cal Kyr BP) was characterised by very slow sediment deposition, erosion and slumping. The latter period corresponds with the mid Holocene minima in March-September equatorial insolation. Sedimentation data are supplemented by 2 mm-spaced scanning XRF records that confirm the significance of the millennial-scale associations and support a long-term ENSO-like (alternating flooding and drought from continental south America) interpretation. We suggest that this regional pattern indicates millennial changes in nearshore ocean currents with the middle Holocene representing a period of intensified upwelling.
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    Regional controls on holocene sedminentation patterns along the Peru continental margin; long term implications for El Niño-Southern Oscillation
    (International Atomic Energy Commission, 2011-03-28) Skilbeck, G; Gutierrez, D; Rein, B; Sifeddine, A; Salvatteci, R; Fink, D; Drruffel, E; Sanchez-Cabeza, JA; Dunbar, R
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