One note on the bomb testing.  I think the West coast would me measuring
isotopes based on the "Red China" dirty bombs used in their development.
Being a Physicist and a recipient  of said  pollution, the topics were
discussed
from time to time.  Southern Hemisphere took the pollution from the
French and
Russian site.  Russian were mostly ICBM testing, they used ground tests
but were
cleaner than the Chinese.  The winds come from the West and brought
Northern Asian
pollution across the US.  Often in snow falls - when as a young person
the health
department kept us from making snow balls or playing in the snow.  (El
Paso).

Our mid Pacific testing - Bikini for example - was at the equator or 2
degrees north...
I have to check my collection but it would be from 100 miles south of
Bikini. more or less.
It is outside your area in any case.

With that said, coming up with a baseline might be tough as many metals
across the
world are said to be above background.  There was talk that large steel
plates
used in the shipyards (Oakland...) that were pre-war in age might have
the best
line.  A company making exotic machines was wringing their hands
awaiting the
scrapping of 'old' yard cranes and their bases.

I don't know how much of that is bunk or pure science.  It came from a
forum of
semiconductor fab people that pay attention to stuff like that for yield.

Good luck with the research - learning and instructing.

Martin


Heather Hawk wrote:
> Hi Shirley,
>
> Thank you so much for your assistance in this quest!  It's been a real
> struggle wrestling prize shells from museums and private collection
> owners!  Since we will be analyzing age and growth using the bomb
> radiocarbon signal (from atomic bomb testing 1950's-70's), as well as
> lead-210 dating, we need shells that lived through that era, and that
> had lived to be old enough so that we can get several samples from the
> shell representing as many years of growth as possible.  This means we
> are looking for Red Abalone ( Haliotis rufescens) and White Abalone
> (H. sorenseni) of around  9 inches or more, of known collection
> location, that were collected after about 1950.
>
> Greg Cailliet ( [log in to unmask]
> <mailto:[log in to unmask]>) and Allen Andrews
> ([log in to unmask] <mailto:[log in to unmask]>) are the
> primary investigators of the CA SeaGrant project "Determination of Red
> and White Abalone age and growth using bomb radiocarbon signal and
> lead dating" at Moss Landing Marine Laboratories.  Their work with
> fish ear bones has validated the life spans of large Atlantic Tarpon
> to 51 years and Orange Roughy to exceed 100 years, as well as
> validating rare deep sea corals to live over 100 years.  The products
> of this work immediately impacts the way fisheries and deep sea
> habitat are managed and/or protected.  California's Abalone species
> have been overexploited due to the lack in fisheries knowledge of
> their life-histories.  Now that the White Abalone is endangered (ESA
> 2001), and the Black Abalone about to be put on the same listing, we
> need to use the resources we have---namely, already-dead wild-caught
> shells---to come up with information and solutions for the restoration
> and management of these species.
>
> Thank you again for your time and assistance.  Have a great day!
> --
> Heather L. Hawk
>
> Graduate Student
> Moss Landing Marine Laboratories
> 8272 Moss Landing Road
> Moss Landing, California 95039 USA
> 678-570-8990
> [log in to unmask] <mailto:[log in to unmask]>

--
Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Founder
IHMSA and NRA Metallic Silhouette maker & member.
http://lufkinced.com/

----------------------------------------------------------------------
[log in to unmask] - a forum for informal discussions on molluscs
To leave this list, click on the following web link:
http://listserv.uga.edu/cgi-bin/wa?SUBED1=conch-l&A=1
Type your email address and name in the appropriate box and
click leave the list.
----------------------------------------------------------------------