Stable isotopes measured on Miocene benthic foraminifera from ODP sites 202-1237 and 184-1146 ...

• Main Authors: Holbourn, Ann E, Kuhnt, Wolfgang, Schulz, Michael, Flores, José-Abel, Andersen, Nils
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2007
• Subjects: Cyclostratigraphy; Composite Core; Leg184; Leg202; Joides Resolution; Ocean Drilling Program ODP; Antarctic; Nils; Pacific; The Antarctic; Antarc*; Ice Sheet
• Online Access: https://dx.doi.org/10.1594/pangaea.658956; https://doi.pangaea.de/10.1594/PANGAEA.658956

One of the most enigmatic features of Cenozoic long-term climate evolution is the long-lasting positive carbon-isotope excursion or “Monterey Excursion”, which started during a period of global warmth after 16.9 Ma and ended at not, vert, similar 13.5 Ma, approximately 400 kyr after major expansion of the Antarctic ice-sheet. We present high-resolution (1-9 kyr) astronomically-tuned climate proxy records in two complete sedimentary successions from the northwestern and southeastern Pacific (ODP Sites 1146 and 1237), which shed new light on the middle Miocene carbon-isotope excursion and associated climatic transition over the interval 17.1-12.7 Ma. We recognize three distinct climate phases with different imprints of orbital variations into the climatic signals (1146 and 1237 d18O, d13C; 1237 XRF Fe, fraction > 63 µm): (1) climate optimum prior to 14.7 Ma characterized by minimum ice volume and prominent 100 and 400 kyr variability, (2) long-term cooling from 14.7 to 13.9 Ma, principally driven by ... : Supplement to: Holbourn, Ann E; Kuhnt, Wolfgang; Schulz, Michael; Flores, José-Abel; Andersen, Nils (2007): Orbitally-paced climate evolution during the middle Miocene “Monterey” carbon-isotope excursion. Earth and Planetary Science Letters, 261(3-4), 534-550 ...