Age of the Dakhleh impact event

Paul Heinrich oxytropidoceras at cox.net
Tue Feb 23 22:36:27 EST 2010

Renne, R. P., H. P. Schwarcz, M. R. Kleindienst,
G. R. Osinski, and J. J. Donovan, 2010, Age of the
Dakhleh impact event and implications for Middle
Stone Age archeology in the Western Desert of Egypt.
Earth and Planetary Science Letters. vol. 29, No. 1-4,
pp. 201–206

http://dx.doi.org/10.1016/j.epsl.2010.01.014

In part the abstract reads:

"Dakhleh Glass comprises a suite of chemically distinctive
and heterogeneous glassy rocks that occur over an area of
ca. 400 km2 in and around the Dakhleh Oasis in central
western Egypt."

and

"The age of the impact event is determined from a
compositionally filtered subset of the data that yield an
isochron age of 145 ± 19 ka."

Dakhleh Oasis, Egypt
http://epsc.wustl.edu/~kieniewicz/dakhleh_oasis.htm
http://www.dakhleh.com/publications.htm

Yours,

Paul H.

Middle Stone Age Impact Identified in Western Desert, Egypt

Paul bristolia at yahoo.com
Sat May 6 21:44:25 EDT 2006

Some archeologists and geologists have published research about
a Middle Stone Age meteorite impact, which occurred in the Western
Desert of Egypt.

Haldemann, A.F.C., M.R. Kleindienst, C.S. Churcher, J.R. Smith, H.P.
Schwarcz, K. Markham, and G. Osinski, 2005, [17.03] Mapping
Impact Modified Sediments: Subtle Remote-Sensing Signatures of
the Dakhleh Oasis Catastrophic Event, Western Desert, Egypt.
Session 17 Dust, Impacts and Earth Atmosphere, 37th AAS Division
for Planetary Sciences Meeting, 31st AAS Historical Astronomy
Division Meeting and the Royal Astronomical Society, 4-9
September 2005, University of Cambridge, UK.

http://www.aas.org/publications/baas/v37n3/dps2005/427.htm

"Ca-Al rich glass (Dakhleh Glass) points to a catastrophic event
between c. 100,000 - 200,000 years ago in this well-studied
African savannah and freshwater lake, Middle Stone Age
environment."

++++

A.F.C. Haldemann, M.R. Kleindienst, C.S. Churcher, J.R. Smith,
H.P. Schwarcz, and G. Osinski, 2005, Volatiles in the Desert:
Subtle Remote-Sensing Signatures of the Dakhleh Oasis
Catastrophic Event, Western Desert, Egypt. Role of Volatiles
and Atmospheres on Martian Impact Craters 2005 Meeting, Lunar
and Planetary Institute, Houston, Texas.

http://www.lpi.usra.edu/meetings/volatiles2005/pdf/3038.pdf

++++

Haldemann, A. F. C., M. R. Kleindienst, C. S. Churcher, J. R. Smith,
H. P. Schwarcz and G. R. Osinski, 2005, Mapping impact modified
sediments: subtle remote-sensing signatures of the Dakhleh Oasis
Catastrophic Event, Western Desert, Egypt. The Sedimentary
Record of Meteorite ImpactsMeeting , Society for Sedimentary
Geology, Springfield, Missouri.

http://geosciences.missouristate.edu/geology/SEPMRC/SEPMRC_program.pdf

"Bracketing by archaeological remains confirms the chronometric
date obtained on the glass of 122,000 ± 40,000 yrs for the
heating event--during the Middle Stone Age occupations of the
oasis area"

Paul H.