Dr. Hailemichael



Soils of the Past: an introduction to paleopedology (G.J. Retallack)
contains a concise answer to your question.  To summarize, in dry climates
carbonate in soil builds up from dust and leftover weathering products at
the rate of .26 g/cm2/yr (for cool desert regions-Las Cruces) to half that
in a wetter and cooler climate or twice the Las Cruces value in a wetter
an somewhat warmer climate (0.51-Roswell).  Hope this helps, but again the
Retallack text is more detailed, as I’m sure other texts are as well.

Dave Mrofka



UC Riverside

Earth Sciences



-----Original Message-----
From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On
Behalf Of Million Hailemichael
Sent: Wednesday, August 06, 2003 2:55 PM
To: [log in to unmask]
Subject: [ISOGEOCHEM] pedogenic carbonates in semiarid soil



Dear all



How long does it takes for a pedogenic carbonate to be formed. Not
neccesarly in the form of a nodule, but even in the form of fine powder in
semi arid environment. Hundreds of years?  Or do we get pedogenic
carbonate in 20 or 30 years.



Thank you



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Million Hailemichael, Ph.D.
Senior Research Associate
Texas A&M University
Department of Rangeland Ecology and Management
Stable Isotope Laboratory
2126 TAMU
College Station, TX 77843-2126



Phone: (979)845-1497
Fax: (979)845-6430
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