Luis:
1. Multiplying variogram by a constant will not change ordinary kriged map. 2. If nugget rises relative to sill, kriged map will be smoother (except if map grid point happens to be at sample point (and gamma(0)=0 during grid estimation)). Pure nugget and all data gives the average of all data for the map 3 Generally higher sill more over all variability in simulation. Higher nugget higher gives greater short range variability in point simulation (Higher nugget generally gives less variability in kriged map). Zero nugget may give greater variability than in raw data due to screen effect and negative weights. For specific results for your kriging and simulation parameters change them and rerun. Robert (Bob) L. Sandefur PE Senior Geostatistician / Reserve Analyst CAM 200 Union Suite 430 Lakewood, Co 80228 [EMAIL PROTECTED] 303 472-3240 (cell) <-best choice 303 716-1617 ext 14 The content of this message may contain the private views and opinions of the sender and does not constitute a formal view and/or opinion of the company unless specifically stated. The contents of this email and any attachments may contain confidential and/or proprietary information, and is intended only for the person/entity to whom it was originally addressed. Any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this email in error please notify the sender immediately by return e-mail and delete this message and any attachments from your system. _____ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of LUIS ARCIA Sent: Wednesday, June 06, 2007 11:06 To: [email protected] Subject: AI-GEOSTATS: The effect of raising and lowering the sill and the absence or presence of a nugget. Importance: High Dear list: I have some doubt about sill and nugget that I want to share with you to help to clarify it: 1) What is the effect of raising and lowering the sill and the absence or presence of a nugget. For example, let's say I'm going to Krig porosity. If the true variance of the porosity data is 15, what happens to the kriged map if I make the sill value 30? what happen if I make it 5?, What happens to the map If I have a nugget of for example 25%?. 2) Instead of Kriging, let's say I'm doing a conditional simulation of porosity. what are the effects raising and lowering the sill (as above) and adding a nugget (as above)? I'll apreciate all your support and cooperation.. with all my respect to you Luis Arcia PDVSA + + 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/
