Path: utzoo!mnetor!uunet!husc6!rutgers!iuvax!pur-ee!pur-phy!hal
From: hal@pur-phy (Hal Chambers)
Newsgroups: sci.misc
Subject: Re: radiation dating
Message-ID: <1102@pur-phy>
Date: 11 Apr 88 12:38:58 GMT
References: <5236@uwmcsd1.UUCP> <1138@PT.CS.CMU.EDU> <5250@uwmcsd1.UUCP> <116@slu70.UUCP> <11009@mimsy.UUCP>
Reply-To: hal@newton.physics.purdue.edu.UUCP (Hal Chambers)
Organization: Purdue Univ. Physics Dept., W. Lafayette, IN
Lines: 12

In article <11009@mimsy.UUCP> chris@mimsy.UUCP (Chris Torek) writes:
 >If the absolute counts of either Rubidium-87 or Strontium-87 were
 >influenced by the event, the ratio function [Rb/Sr](t) might have a
 >sudden discontinuity.  This can be checked, however, by choosing two
 >more isotopes; as the number of isotopes checked goes up, the
 >probability of error goes down.

As an example of the danger of using a single isotope ratio, several
historic (19th centry) lava flows at Mauna Kea (sp?) have a Rb/Sr date
of several hundred million years.

Hal Chambers