The enigma of rare Quaternary oolites in the Indian and Pacific Oceans: A result of global oceanographic physicochemical conditions or a sampling bias?

Authors

Stephen Gallagher, University of Melbourne
L Reuning, RWTH Aachen University
T Himmler, Geological Survey Of Norway
J Henderiks, Uppsala University
D De Vleeschouwer, University of Bremen
J Groeneveld, University of Bremen
A Rastigar Lari, University of Western Australia
C Fulthorpe, University of Texas at Austin
K Bogus, University of Exeter
W Renema, Naturalis Biodiversity Center
Helen V. McGregor, University of WollongongFollow
M Kominz, Western Michigan University
G Auer, Japan Agency for Marine-Earth Science and Technology
S Baranwal, Arctic University of Norway
S Castaneda, University of Massachusetts
B A. Christensen, Adelphi University
D R. Franco, National Observatory
Michael Gurnis, California Institute of Technology
C Haller, University of South Florida
Y He, Zhejiang University
T Ishiwa, University of Tokyo
H Iwatani, University of Hong Kong
R Jatiningrum, Akita University
C Korpanty, University of Queensland
E Y. Lee, Chonnam National University
E Levin, University of California Davis
B L. Mamo, Macquarie University, University of Hong Kong
C M. McHugh, Queens College
B Petrick, Newcastle University
Donald C. Potts, University of California Santa Cruz
H Takayanagi, Tohoku University
W Zhang, Nanjing University

RIS ID

130841

Publication Details

Gallagher, S. J., Reuning, L., Himmler, T., Henderiks, J., De Vleeschouwer, D., Groeneveld, J., Rastigar Lari, A., Fulthorpe, C. S., Bogus, K., Renema, W., McGregor, H. V., Kominz, M. A., Auer, G., Baranwal, S., Castaneda, S., Christensen, B. A., Franco, D. R., Gurnis, M., Haller, C., He, Y., Ishiwa, T., Iwatani, H., Jatiningrum, R. S., Korpanty, C. A., Lee, E. Y., Levin, E., Mamo, B. L., McHugh, C. M., Petrick, B. F., Potts, D. C., Takayanagi, H. & Zhang, W. (2018). The enigma of rare Quaternary oolites in the Indian and Pacific Oceans: A result of global oceanographic physicochemical conditions or a sampling bias?. Quaternary Science Reviews: the international multidisciplinary research and review journal, 200 114-122.

Abstract

Marine ooids are iconic indicators of shallow seawater carbonate saturation state, and their formation has traditionally been ascribed to physicochemical processes. The Indo-Pacific stands out as a region devoid of oolites, particularly during the Quaternary: the “ooid enigma”. Here we present results from recent coring by the International Ocean Discovery Program (IODP Expedition 356) off west Australia that shows that ooid horizons are common in Pleistocene strata up to 730,000 years old. Extensive “ooid factories” were created due to the presence of long-lived tidally influenced flat–topped tropical platforms suitable for intermittent ooid accretion over hundreds to thousands of years during highstands and times of lower sea level. This work suggests marine ooids may actually be more common in Indo-Pacific than previously reported. Past global ocean alkalinity was elevated during Pleistocene glacial periods and continental climate was generally more arid in the Indo-Pacific region compared to interglacials and the Holocene. Therefore, increased aridity associated with higher alkalinity conditions during the glacials facilitated ooid precipitation on adjacent tropical carbonate platforms particularly offshore from arid Australia. This confluence of factors suggests that more “ooid factories” may be encountered by further coring Indo-Pacific regions with Pleistocene flat long-lived carbonate shelves. However, Indo-Pacific Quaternary ooid occurrences outside Australia are rare, suggesting that the Northwest Shelf may be a unique archive of this non-skeletal precipitate. Further investigations into the petrography and geochemistry of pre-Holocene ooid occurrences will provide insights into their origin and the relative role of biotic, physicochemical and other factors in their formation.