July 31st, 1999
Carl,
My source of information for this has come from the web site of "Society of Exploratory Geophysicists" at:www.seg.org. Once your on their homepage, click on "Publications" then "Geoarchives". Select the year 1997 and then click on the Sept./Oct. issue. About 3 or so papers from the bottom of the listing, is the article entitled "Some Case Histories of source discrimination using time-domain spectral IP" which is in Adobe Acrobat format. This paper very well describes all of the parameters involved for doing a IP survey, and then goes on to give several case histories (some of which discover Gold). Turns out, just by using the fall-time of the return pulse was all that was necessary for determining the kind of ore. There's also a nifty little Table that shows the Time Constants for the different metals and you'll see how Gold is in a class by itself. I will be building equipment for this method in the fall, which includes making a simple/crude handheld oscilloscope with LED's as I can't afford the $215 one yet sold by JAMECO (that Forrest Mims is one clever guy!). I hope this helps.
Randy Seden
Carl,
My source of information for this has come from the web site of "Society of Exploratory Geophysicists" at:www.seg.org. Once your on their homepage, click on "Publications" then "Geoarchives". Select the year 1997 and then click on the Sept./Oct. issue. About 3 or so papers from the bottom of the listing, is the article entitled "Some Case Histories of source discrimination using time-domain spectral IP" which is in Adobe Acrobat format. This paper very well describes all of the parameters involved for doing a IP survey, and then goes on to give several case histories (some of which discover Gold). Turns out, just by using the fall-time of the return pulse was all that was necessary for determining the kind of ore. There's also a nifty little Table that shows the Time Constants for the different metals and you'll see how Gold is in a class by itself. I will be building equipment for this method in the fall, which includes making a simple/crude handheld oscilloscope with LED's as I can't afford the $215 one yet sold by JAMECO (that Forrest Mims is one clever guy!). I hope this helps.
Randy Seden
Comment