"It seems to decay exponentially over tens of thousands of years, corraborating Anbar's numbers very nicely."
--Actually I think in the mainstream model, you would rather use atmospheric iridium precipitation models. Your not going to need to use ocean depths to analyze what ws deposited without the presence of water, let alone ocean depths. Unless of course I misunderstand the information that is actually included in the full article.
I just spotted this page which may have some information valuable to this discrepancy:
http://es.epa.gov/ncer/final/grants/96/air/ondov2.html
Some other resources which like the other, am unable to access:
Hansen, H. J., Rasmussen, K. L., Gwozdz, R. & Kunzendorf, H., 1987.
Iridium-bearing carbon black at the Cretaceous-Tertiary boundary. Bulletin
of the Geological Society of Denmark, 36, 305-314.
Lerbekmo, J. F., Sweet, A. R. & St. Louis, R. M., 1987. The relationship
between the iridium anomaly and palynological floral events at three
Cretaceous-Tertiary boundary localities in western Canada. Geological
Society of America Bulletin, 99, 325-330.
Tredoux, M., De Wit, M. J., Hart, R. J., Linsay, N. M., Verhagen, B. &
Sellschop, J. P. F., 1988. Chemostratigraphy across the Cretaceous-Tertiary
boundary and a critical assessment of the iridium anomaly. Journal of
Geology, 97, 585-605.
Crockett, J. H., Officer, C. B., C., W. F. & Johnson, G. D., 1988.
Distribution of noble metals across the Cretaceous/Tertiary boundary at
Gubbio, Italy: Iridium variation as a constraint on the duration and nature
of Cretaceous/Tertiary boundary events. Geology, 16, 77-80.
Robin, E., Boclet, D., Bont, P., Froget, L., Jhanno, C. & Rocchia, R.,
1991. The stratigraphic distribution of Ni-rich spinels in
Cretaceous-Tertiary boundary rocks at El Kef (Tunisia), Caravaca (Spain)
and Hole 761C (Leg 122). Earth and Planetary Science Letters, 107, 715-721.
(this reference also contains a discussion of the Ir anomalies in these
sections).
Colodner, D. C., Boyle, E. A., Edmond, J. M. & Thomson, J., 1992.
Post-depositional mobility of platinum, iridium and rhenium in marine
sediments. Nature, 358, 402-404.
Sawlowicz, Z., 1993. Iridium and other platinum-group elements as
geochemical markers in sedimentary environments. Palaeogeography,
Palaeoclimatology, Palaeoecology, 104, 253-270.
Wang, K., Attrep, M., Jr. & Orth, C. J., 1993. Global iridium anomaly, mass
extinction, and redox change at the Devonian-Carboniferous boundary.
Geology, 21, 1071-1074.
Elliot, D. H., Askin, R. A., Kyte, F. T. & Zinsmeister, W. J., 1994.
Iridium and dinocysts at the Cretaceous-Tertiary boundary on Seymour
Island, Antarctica: implications for the K-T event. Geology, 22, 347-355.
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