Tuesday, September 24, 2013

Prepping the Avaceratops

It's long overdue for an update, and since the weather in Montana isn't cooperating with our plans to head up there today and finish our season in the Judith River, it's as good a time as any to show what we've gotten done in the lab.

Newer modification to Scott Hartman's illustration: now with no nose horn
Work is slow due to the fact that the bone of this juvenile animal is fairly soft and crumbly when not consolidated, and that many bones are jackstrawed together in larger blocks. Each bone is individually removed from its jacket and checked against the field inventory. When it's a new bone, not exposed in the field excavation, we give it a separate accession number to keep track of it in the lab.

Jacket disassembly with documentation

Typical multi bone jacket before removal
We're primarily using air scribes on the "firm" sanstone matrix, with air abrasion for the detailed work. In some cases, such as the extensive skin impressions over the left hip and rib area, we skip the abrasion in order to preserve the skin as best we can.

Skin texture preserved on the right ilium
Once out of the rock, we restore the cracks and missing bits with epoxy putty in order to get the bones ready for molding. Our current plan, due to the completeness of the skull and skeleton, is to mold everything and do a full skeletal restoration. The animal looks like it will be less than 1.5m tall at the hips - very manageable for a ceratopsian.
Molding jaw parts prior to laser scanning