Blog 3: Barking Owl Field Camp (Day 5-7)
Time is spent describing and demonstrating our sampling techniques with our Aboriginal co-workers Scottie, Mark and Chubby. We explain how we carefully remove very small samples and often reveal, rather than damage any of the underlying pigment. Each sample is taken with the approval of a Traditional Owner.
Dating Technique 2-Radiocarbon Dating: Damien Finch’s PhD research focuses on dating the mud wasp nests we commonly see across the rock art panels. Damien uses a small dental chisel to remove the tiniest of samples which are returned to the labs where organic carbon is extracted from within the nest for dating. The principle of Radiocarbon dating is based on the decay of 14Carbon at a known rate following the death of the organism it came from. Comparing the amount of 14C in a dead organism to modern levels gives us an estimate of when that organism died and consequently, the age of the wasp nest. By sampling nests over, under or bracketing rock art pigment, Damien can provide maximum and minimum ages for the rock art styles.
On day 7 we crash through 4 km of spinifex to ‘Bichrome Rock.’ It takes teamwork to access some of the difficult- to-reach samples on the spectacular rock art panels (sorry Jordy!) During the morning three helicopters arrive transporting RAA directors and guests who are keen to learn about our work. Director Bruce Cameron locates an excellent site with a large crocodile motif which we nickname ‘Bruce’s Crocodile’ and from which we gather a range of samples. We also identify target sites for the ANSTO Cosmogenics team due to arrive the next day.
Our camp has expanded from the core 7 to a livelier 14 with the arrival of Professors Andy Gleadow and Janet Hergt from Melbourne University, RAA Director Henric Nicholas and his wife Minny, Professor Mark Harrison from The University of California, LA, his wife Sue and All North chopper pilot Nick Sundblom. It was wonderful to discuss our preliminary lab results and future plans with a range of such interesting people over the camp fire. In my (British) mind the odds of being eaten by a rogue salt water croc at bath time had suddenly dramatically decreased! Campground real estate is at an all-time high as campers scramble for the ‘best view’, ‘closest dunny run’…. ‘Furthest pitch from the camp’s mystery snorer’….