Washing Technique Analysis for Microvertebrate Fossils
Access Type
Campus Access Only
Entry Number
49
Start Date
4-5-2017 12:00 PM
End Date
4-5-2017 1:00 PM
Department
Environmental Science
Abstract
The Late Jurassic Morrison Formation in Wyoming has been known for over a century for it’s dinosaurian fauna. But it contains a much more diverse vertebrate fauna including mammals, crocodiles and croc relatives, fish, lizards, and smaller dinosaur remains. The techniques for recovering these smaller materials are different from the quarry excavations for large dinosaurs. Rock matrix is gathered in bulk, and then reduced using a variety of methods to remove unwanted rock while preserving the delicate microvertebrate fossils. This project examined the different methods of matrix reduction in the literature, then experimented with a new technique to determine if it resulted in sufficient matrix reduction and fossil recovery.
The system used in this study utilizes paint sieves. The process we used involves a five gallon bucket, a one gallon paint sieve / five gallon paint sieve, a bubble wand, and an air pump. We placed the bubble wand on the bottom of a filled five gallon bucket with a one gallon paint sieve hanging from a stick that has been placed overtop of the five gallon bucket. We are able to compare the efficiency of the two processes by measuring percent reduction of the matrix.
We used different washing techniques but the last, and most efficient technique involved soaking a 1 gallon paint sieve for two days and agitating it after each day of soaking. The average percent reduction was ~72%. We continued to use this procedure for the rest of the experiment.
Faculty Mentor(s)
Dr. Brooke Haiar
Washing Technique Analysis for Microvertebrate Fossils
The Late Jurassic Morrison Formation in Wyoming has been known for over a century for it’s dinosaurian fauna. But it contains a much more diverse vertebrate fauna including mammals, crocodiles and croc relatives, fish, lizards, and smaller dinosaur remains. The techniques for recovering these smaller materials are different from the quarry excavations for large dinosaurs. Rock matrix is gathered in bulk, and then reduced using a variety of methods to remove unwanted rock while preserving the delicate microvertebrate fossils. This project examined the different methods of matrix reduction in the literature, then experimented with a new technique to determine if it resulted in sufficient matrix reduction and fossil recovery.
The system used in this study utilizes paint sieves. The process we used involves a five gallon bucket, a one gallon paint sieve / five gallon paint sieve, a bubble wand, and an air pump. We placed the bubble wand on the bottom of a filled five gallon bucket with a one gallon paint sieve hanging from a stick that has been placed overtop of the five gallon bucket. We are able to compare the efficiency of the two processes by measuring percent reduction of the matrix.
We used different washing techniques but the last, and most efficient technique involved soaking a 1 gallon paint sieve for two days and agitating it after each day of soaking. The average percent reduction was ~72%. We continued to use this procedure for the rest of the experiment.