Precambrian impact ejecta blanket found in Scotland
Paul bristolia at yahoo.comMon Mar 24 12:09:42 EDT 2008
Amor, K., Stephen P.Hesselbo, Don Porcelli, Scott Thackrey, and
John Parnell, 2008, A Precambrian proximal ejecta blanket from
Scotland. Geology..vol. 36, no. 4, pp. 303-306.
In part theabstract reads:
“The StacFada Member of the Precambrian Stoer Group in Scotland
haspreviously been described as volcanic in origin. However,
shockedquartz and biotite provide evidence for high-pressure shock
metamorphism, while chromium isotopevalues and elevated
abundancesof platinum group metals and siderophile elements
indicateaddition of meteoritic material. Thus, the unit is
reinterpretedhere as having an impact origin.”
This unit isas much as 20 meters thick in places.
http://www.gsajournals.org/perlserv/?request=get-abstract&doi=10.1130%2FG24454A.1
Related paper:
Young, G. M., 2002, Stratigraphy and geochemistry of volcanic
mass flows in the Stac Fada Member of the Stoer Group,
Torridonian, NW Scotland. Royal Society of Edinburgh Transactions:
Earth Sciences. vol. 93, no. 1, pp. 1-16.
Yours,
Paul H.
No comments:
Post a Comment