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Geology/Radiometric dating of a rock


I have a rock from the Susquehanna River and I am trying to find somewhere where they can date it. It is probably quite old based on the 250 million year age of the river. Any suggestions would be appreciated.


Is this a rock that you picked up from the river bed or collected from an outcrop?  If it is from an outcrop, nearly an geologist experienced in that area will be able to give you a pretty good assessment as to age.  If the rock was collected above the falls, it is likely sedimentary and we can pinpoint that age pretty good.  If it was collected below (or near) the falls and is metamorphic aging is more difficult because do you want the age of the metamorphism or the age of the precursor.

Radiometric dating is expensive and typically involves some grant funded research.  And, if the rock is not collected in just right the way the radiometric techniques might provide reliable results.

Does this help?



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Fraser Hamilton


I have over 15 years of professional experience in the environmental geology field. I am well versed in general geology types of questions and answers. In addition I have a keen understanding of physical stratigraphy (especially in the Valley and Ridge of Central PA) and cycles.


Eight years of education, fifteen years of professional experience. Have worked or studied in ME, PA, TX, KY, IN, TN, OH, WA and Scotland.

Geological Society of America
American Association of Petroleum Geologists
Properties Magazine
Cleveland Bar Association
Cleveland Engineering Society

BA Geology/Math, University of Maine at Farmington
MA Geology - Physical Stratigraphy, Temple University
Post Grad Studies Geology - Texas A&M University

Awards and Honors
Distinguished graduate teaching award, Temple University

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