Thanks for helping me, actually I already corrected this error and get the following image,
![terrain](/c/portal/getImageAttachment?filename=terrain.JPG&userId=133435)
do you think is well done in Mathematica? Or I could make some modifications to meet the conditions outlined in the web page that I shared.
I attached my new file where I have made some changes, I hope you can see it, even still believe it can be improved. Greetings to all.
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