sebastiano trevisani wrote:
I would like also to suggest another point: really often there is a relationship between topographic elevation and hydraulic head data values; in this case an external drift approach could be useful.
Here is a reference to a study where the relationship between topography and hydraulic head was exploited through cokriging:
Hoeksema et al., Cokriging for estimation of water table elevation, Water Resources Research, 25(3), 1989.
and another study where DEM-derived variables (elevation and topographic index) were used as external drift variables:
Desbarats et al., On the kriging of water table elevations using collateral information from a digital elevation model, J. Hydrology, 255, 2002.
Probably also of interest: Tonkin and Larson, Ground Water, 40, 2002, and Volpi and Gambolati, Adv. Water Resources, 1, 1978, used logarithmic trends based on the reasoning that hydraulic head trends near pumping wells can be approximated as radially logarithmic.
-- Bob Harrington, Hydrologist Inyo County Water Department 163 May St. Bishop, CA 93514 (760) 872-1168 [EMAIL PROTECTED] + + To post a message to the list, send it to [email protected] + To unsubscribe, send email to majordomo@ jrc.it with no subject and "unsubscribe ai-geostats" in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
