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Up one level- Douglas Kennett
- Murray Springs close-up
- Nanometer-sized diamonds occur at the base a layer of sediment directly above the remains of extinct animals (mammoths, dire wolves, etc.) and artifacts from Clovis culture at Murray Springs, Arizona.
- Murray Springs site
- A view of the site at Murray Springs, Arizona, where nanometer-sized diamonds occur at the base a layer of sediment directly above the remains of extinct animals (mammoths, dire wolves, etc.) and artifacts from Clovis culture.
- Nanodiamond photomicrographs
- Results from three sites: A-Lake Hind, Canada; B-Bull Creek, Oklahoma; and C-Murray Springs, Arizona. Stratigraphic profiles, shown at left for each site, show that nanodiamonds only in sediment of the Younger Dryas Boundary. Above-ground iridium levels appear at Lake Hind and Murray Springs. White arrows on the Lake Hind image show examples of where nanodiamonds appear in the carbon mix. Color-coded arrows in the upper right of each image refer to indexed spacing (in angstroms). The images are the results of transmission electron microscopy and the use of selected area diffraction patterns that focus on Younger Dryas Boundary sediment. (Image use courtesy of AAAS)
- North American Overview
- Map shows currently known distribution of nanodiamonds in Younger Dryas Boundary sediments across North America: (1) Murray Springs, Arizona: 200 parts per billion; (2) Bull Creek, Okla.: 100 ppb; (3) Lake Hind, Manitoba, Canada: 70 ppb; (4) Chobot, Alberta, Canada: 10 ppb; (5) Gainey, Mich.: 3,700 ppb; (6) Topper, SC: 108 ppb. In transmission electron microscopy photomicrographs, diamonds are paired with associated selected area diffraction patterns of carbon spherules from the Chobot (A and B) and Topper sites (C and D). Arrows on photomicrographs highlight examples of diamonds within the amorphous carbon matrices of spherules. Arrows on SADPs are indexed d-spacings (in angstroms). (Image courtesy of AAAS; map by Jake Bartruff)
- Pat Barlein, professor of geography
