[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: computed 14C and 13C values in NETPATH




> When 13C is selected as a costrains, computed 13C values is almost same
comparing with the observed value in radiocarbon calculation by using
netpath, but calculated 14C values quite different from observed 14C
respectively 6.34 and 0.33. Also examples 5, 6 and 7 in netpath manual,
this case is present.

I'm not sure what you mean. In example 5, the first model has computed C13
= -13.6, which is substantially different from -6.2. Niel goes on to try
different models that are consistent between the computed and measured C13.

> Do we have to take in to consideration only calculated and observed
values of 13C?

For a mole-balance model to be possible, it must have a computed C13 that
is consistent with measured values. If the model is not consistent with the
C13, it can not be correct. If it is consistent, it may or may not be the
correct model. It is possible to have two models that account for C13, but
give different C14 ages as seen in the second and fourth models of example
5.

David


David Parkhurst (dlpark@xxxxxxxx)
U.S. Geological Survey
Box 25046, MS 413
Denver Federal Center
Denver, CO 80225

Project web page: https://wwwbrr.cr.usgs.gov/projects/GWC_coupled




Project Home Page
Complete Water Resources Division Software
USGS Home Page
Water Resources Division Home Page
NRP Home Page
Help Page
USGS Privacy Statement       

Please note that some U.S. Geological Survey (USGS) information accessed through this page may be preliminary in nature and presented prior to final review and approval by the Director of the USGS. This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the sole responsibility of the user.

Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government. 


The URL of this page is: https://wwwbrr.cr.usgs.gov/projects/GWC_coupled/phreeqc/mail/msg00659.html
Email:dlpark@usgs.gov
Last modified: $Date: 2005-09-13 21:04:21 -0600 (Tue, 13 Sep 2005) $
Visitor number [an error occurred while processing this directive] since Jan 22, 1998.