Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!ucsd!sdcsvax!ucsdhub!hp-sdd!hplabs!hpda!hpcuhb!hp-ses!hpcea!hpldsla!oreilly
From: oreilly@hpldsla.HP.COM
Newsgroups: sci.space
Subject: Re: Primordial Hydrocarbons
Message-ID: <1850009@hpldsla.HP.COM>
Date: 28 Mar 89 03:20:36 GMT
References: <291@v7fs1.UUCP>
Lines: 12

Mike Van Pelt writes;
> The outfit in Sweden found methane... the gas
> had been verified as being of non-biological origin, but they
> didn't explain how they had verified this.

Carbon contains two stable isotopes, carbon-12 and carbon-13.
During photosynthesis, the carbon retained in plant tissue is enriched
in carbon-12 (relative to non-biogenic carbon, such as diamond). Thus methane
of biogenic origin is usually enriched in carbon-12.

Tom O'Reilly
oreilly@hpldsla