Electron micrographs of mineral grains and fossils separated using Electric Pulse Disaggregation
Electric Pulse Disaggregation (EPD) departs from traditional methods of rock comminution by preferentially fracturing rock along natural grain boundaries. This process offers the following benefits to mineralogy and fossil preparation laboratories:
Pulsed power involves the precise release of ultra short, high power bursts of electrical energy. When a sufficiently powerful pulse of electrical energy is conducted through rock, plasma streamers are formed which tend to propagate along mineral grain boundaries. These streamers create high internal tensile stresses which tend to fracture materials along grain boundaries.
- Preserves mineral grain morphology
- Reduces the production of fines/slimes
- Preserves natural grain size distribution
- Allows concentration of target mineral fractions by seiving
Scientific aspects of this technology were pursued with Dr. Paul Weiblen of the University of Minnesota, Minneapolis and with Dr. N.S. Rudashevsky of Mechanobr Technical Corporation in St. Petersburg, Russia.
- Saini-Eidukat, B., and Weiblen, P.W., 1996. A new method of fossil preparation, using high-voltage electric pulses. Curator, 39: 139-144.
- Rudashevsky, N.S., Burakov, B.E., Lupal, S.D., Thalhammer, O.A.R., and Saini-Eidukat, B., 1995. Liberation of accessory minerals from various rock types by electric pulse disintegration - method and applications: Transactions, Institution of Mining and Metallurgy, v. 104, pp. C25-C29.
Weiblen, P.W., Saini-Eidukat, B., and Rudashevsky, N.S., 1995. The use of electric pulse disaggregation in studies of gabbroic rocks. In Petrology and Metallogeny of Volcanic and Intrusive Rocks of the Midcontinent Rift System, Proceedings, IGCP Project 336 International Field Conference and Symposium, Duluth, Minnesota, Aug. 19-Sept. 1, p. 203.
- Rudashevsky, N.S., Weiblen, P.W., Stoynov, H., and Saini-Eidukat, B., 1995. Products of electric pulse disaggregation of some Keweenawan rocks, Institute on Lake Superior Geology Proceedings, 41st Annual Meeting, Marathon, Ontario, v. 41, part 1, p. 61.
Saini-Eidukat, B., Pederson, B., and Weiblen, P.W., 1995. Use of electric pulse disaggregation to liberate fossils from North and South Dakota sediments. North Dakota Academy of Sciences Annual Meeting, Bismarck, ND, April 20-21.
On the following pages, are a few examples of the use of Electric Pulse Disaggregation as a mineral and fossil separation tool.
Dept. of Geosciences
Dept. #2745, P.O. Box 6050
North Dakota State University
Fargo ND 58108-6050
tel. 701-231-8785 fax 701-231-7149