te: Thu, 1 Jun 1995 15:33:32 -0700 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Mark Hall Subject: BM dates Was there ever a follow-up on the British Museum radiocarbon dates BM 1700-BM 2315? I've seen the notice in Antiquity that these dates may be as much as 200-300 years too young; did they ever publish a correction or any further notice on these dates? Thanks, Mark Hall hall@qal.berkeley.edu Archaeological Laboratory Dept. of Anthropology Kroeber Hall UC Berkeley Berkeley, CA 94720 ========================================================================= Date: Fri, 2 Jun 1995 09:07:34 GMT Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: "A.Bayliss" Subject: Re: BM dates See Radiocarbon vol 32 (1990) p59-79 for the re-evaluation of these dates. Alex Bayliss (English Heritage) ========================================================================= Date: Mon, 5 Jun 1995 10:33:08 -0400 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: "Robert H. Tykot" Subject: Re: BM dates >Was there ever a follow-up on the British Museum radiocarbon dates >BM 1700-BM 2315? I've seen the notice in Antiquity that these dates may >be as much as 200-300 years too young; did they ever publish a correction >or any further notice on these dates? > Yes; reference follows. Bowman, S.G.E.; Ambers, J.C.; Leese, M.N. 1990 Re-evaluation of British Museum radiocarbon dates issued between 1980 and 1984. Radiocarbon 32(1):59-79. ********************************************************** * Robert H. Tykot Tykot@Fas.Harvard.Edu * * Archaeometry Laboratories 617 496-8991 * * Department of Anthropology 617 495-8925 (fax) * * Harvard University * * Cambridge, MA 02138 USA * ********************************************************** ========================================================================= Date: Wed, 7 Jun 1995 01:32:37 -0400 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Michael Nelson Subject: Re: BM dates See Radiocarbon vol. 32 (1990) p59-79 for re-evaluation of these dates. ========================================================================= Date: Mon, 12 Jun 1995 07:54:02 -0700 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Mark Hall Subject: Re: C14-L Digest - 4 Jun 1995 to 11 Jun 1995 Thanks to all who replied on my query about the BM dates. Best, Mark Hall hall@qal.berkeley.edu ========================================================================= Date: Thu, 15 Jun 1995 21:58:16 +0100 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: "T.J.M.Steele" Subject: clovis and C14 isochron mapping??! Hi, *WARNING: NAIVE QUERY* My group is working on hunter-gatherer colonization dynamics. We puzzle that no- one has attempted a hyper-modest equivalent of isochron mapping for the first Americans - namely, a statistical analysis of C14 dates from the earliest Holocene of North and South America which could address at least the question of the existence of a north-to-south gradient. At present, the arguments seem to centre on the validity of 'outlier' (sc. too-early) dates, and it's perfectly possible for people to assert that the 'eyeballed' trend is for earliest dates in the *South* (I've even had that put to me at Conferences). Surely someone has tried some averaging of the total Paleoindian date sample, to check this out? (If not, we've decided we're going to have to - and we'd HATE to undertake such a chore if someone else has already made a Patagonia. Science 228:1110-1112 Martin, P.S. 1966. Africa and Pleistocene overkill. Nature 212:339-342. Martin, P.S. 1967. Prehistoric overkill. in Martin and Wright Martin, P.S. 1967. Pleistocene overkill. Natural History 76:32- 38. Martin, P.S. 1973. The discovery of America. Science 179:969-974. Martin, P.S. and Klein, R.G. 1984. Quaternary Extinctions a prehistoric revolution. Univ. Arizona Press, Tucson. Martin, P.S. and Wright, H.E., Jr. 1967. Pleistocene extinctions, the search for a cause. Yale Univ. Press, New Haven. Owen Owen K. Davis, Ph.D. Phone 520 621 7953 Professor of Geosciences FAX 520 621 2672 University of Arizona palynolo@geo.arizona.edu Tucson, AZ 85721 http://www.geo.arizona.edu/palynology ========================================================================= Date: Fri, 16 Jun 1995 15:17:27 -0700 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Albert Zondervan Organization: R.U.G. Wisk. & Natuurwetenschappen Subject: "slightly" enriched Who can tell me where I can find/order graphite or carbon dioxide (or ???) with >100 pMC, let's say up till TEN times modern. I wanna investigate if this is feasible for use as a working standard and tuning material in AMS. [until now we do with the Oxalics and C6] Albert Zondervan CIO/RUG ========================================================================= Date: Fri, 16 Jun 1995 18:28:52 -0400 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Greg Laden Subject: Re: clovis and C14 isochron mapping??! In-Reply-To: <199506152058.VAA24994@willow.soton.ac.uk> On Thu, 15 Jun 1995, T.J.M.Steele wrote: > > My group is working on hunter-gatherer colonization dynamics. We puzzle that no- > one has attempted a hyper-modest equivalent of isochron mapping for the first > Americans - namely, a statistical analysis of C14 dates from the earliest > Holocene of North and South America which could address at least the question > of the existence of a north-to-south gradient. ... I don't know of anyone having done this, but there was a time, maybe 20 years ago, when it looked like Clovis would have started in the northeast and spread from there! I remember discussing this with Russel Barber, who teaches now somewhere in southern California. Sounds interesting, we are all eagerly awaiting your results! Oh, by the way, you may want to look up Mitch Mullholland, who was last I know at UMASS Amherst. Seems to me he may have done something like this, although not for paleoindians. Cheers, GTL Greg Laden Department of Anthropology Harvard University 11 Divinity Avenue Cambridge MA 02138 gladen@fas.harvard.edu ========================================================================= Date: Mon, 19 Jun 1995 10:33:12 +1200 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: "Sparks, Rodger" Subject: slightly enriched - Reply If you have access to a deuterium accelerator beam you can make such material by bombarding ordinary graphite and use the 13C(d,p)14C reaction. I don't know about using it as a standard, but it can work well as a slightly-hot (or very hot if you want!) tune-up target. Less than 2 MeV is quite enough energy. Rodger Sparks ========================================================================= Date: Mon, 19 Jun 1995 13:22:06 +0200 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Magnus Hedberg Subject: Re: "slightly" enriched >Who can tell me where I can find/order graphite or carbon dioxide (or ???) >with >100 pMC, let's say up till TEN times modern. I wanna investigate if >this is feasible for use as a working standard and tuning material in AMS. >[until now we do with the Oxalics and C6] > >Albert Zondervan >CIO/RUG According to the catalog from the company "American Radiolabeled Chemicals, Inc" they supply C14 in the form of carbon dioxide and carbon monoxide. They also have C14 in various other forms. The carbon dioxide is delivered as a gas in break seal. The smallest amount in the catalog is 1 mCi for a cost of $169 + shipping. 1 mCi is allot. Only a small fraction of this is necessary to make a large amount of standard material. I have not tried this myself and I do not now if there are other suppliers which have better material. Perhaps it is possible to buy smaller amounts on request. I have sent them a message to inquire about this. I am also interested in making a laboratory standard with something like 10 to 20 times modern. In my case I will use it in our proportional detectors. The address to the company is: American Radiolabeled Chemicals, Inc. 116 24 Bowling Green Drive St. Louis, MO 63146 Tel. (314) 991 4545 Fax: (314) 991 4692 I belive that the C14-laboratory in Heidelberg use a modern standard with a high modern activity. Perhaps they can give you more information. Magnus Hedberg (lig-magnus@nrm.se) Laboratory for Isotope Geology Swedish Museum of Natural History Box 50007 104 05 Stockholm SWEDEN ========================================================================= Date: Mon, 19 Jun 1995 10:31:24 -0400 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: "G.M. Milton" Subject: Re: "slightly" enriched In order to improve the QA of environmental C14 measurements made by monitoring labs at nuclear power plants, the Environmental Research Branch at the Chalk River Laboratories has prepared a number of environmental samples for inter- comparison. We recently sent out 2 samples of ground, homogeneized vegetation, containing roughly twice and eight times "modern" to twelve labs. To date half have returned their measurements. A combustion step would be required to produce the CO2 you need, but if you are interested we would be happy to ship portions of these samples to you. Naturally we'd like to add your results when we are ready to analyze the data received. Best wishes, Gwen Milton ========================================================================= Date: Tue, 20 Jun 1995 14:51:30 +0200 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Comendeiro Jose Hallo: My name is Jose Comendeiro and I new at this listserv. I work as radiochemist at lab of radiometrie in Slovakia. We are not making carbon dating but We are dterminating the activity of C-14 by LSQ of environmental samples, mainly in water. I need information about how determinate total C-14 , organic and inorganic, in voluminuos samples of water? Some methods only determinate C-14 as CO2. Do you know the method of isolating organic carbon when the sample is irradiated with u.v. light and the carbon dioxide formed blown out by carbon dioxide-free air? I read that the dissolved organic carbon of 15 litres of water can be oxidized up to over 90 percent during an irradiation period of 18 hours by the use of a 100-W mercury lamp. What do you think about? Some information would be very appreciate! Thank you in advance, Jose Comendeiro Laboratorium of radiometry and radioecology RI pavilon University of Agricultury Nitra A.Hlinku 2 949 76 Nitra Slovak Republic e-mail: comendei@uniag.sk ========================================================================= Date: Wed, 21 Jun 1995 12:59:55 +0200 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Peter Becker-Heidmann Subject: Re: coal contamination In-Reply-To: <950430.140845.EDT.DTHIEME@UGA.CC.UGA.EDU> from "Donald M. Thieme" at Apr 30, 95 02:05:41 pm Donald M. Thieme wrote: > > I am doing my dissertation on the alluvial chronology of the > Wyoming Valley in Pennsylvania. Glacial scour exposed coal seams > so I am having to try to avoid coal that occurrs as clasts in some > prehistoric as well as historic deposits. > > Any references on coal contamination (other than the Meadowcroft stuff) > would be of interest to me. For example, does delta-13-C reflect > the extent to which "old" carbon contaminates a sample? > We have the problem of heavy browncoal contamination in soils of Eastern Germany. It can be easily detected and quantified by 14C-dating. However, the delta-13C is ca. -25 permill PDB for both coal and soil. For more information you may contact Michael W. I. Schmidt University of Bochum Soil science group NA 6/131 44780 Bochum, Germany Regards Peter --------------------------------------------------------------------- Peter Becker-Heidmann : : /YY\ : : Institut fuer Bodenkunde : |YYYY|. : Allende-Platz 2, D-20146 Hamburg, GERMANY : . \YY/. : : Phone: +49 40 4123 2003, Fax: +49 40 4123 2024 __:__:_||__:__:__ E-Mail: PBeckerH@Uni-Hamburg.de SOILSOILSOILSOILS --------------------------------------------------------------------- ========================================================================= Date: Thu, 22 Jun 1995 09:59:08 -0400 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Jeff Lentz Subject: Historical Atmospheric C14 Level Data Sought I am searching for data on atmospheric C14 levels, dating back over the past 100-200 years (or as far as has been recorded) to verify (or disprove) a rumor that seems to be proliferating about increasing amounts. Any suggestions would be appreciated. Thanks. Jeff Lentz Oak Ridge National Laboratory ========================================================================= Date: Mon, 26 Jun 1995 09:47:09 -0400 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: "G.M. Milton" Subject: Re: Historical Atmospheric C14 Level Data Sought For obvious reasons most of the routine measurements of C14 date from the late 50's or early 60's, but there have been a number of measurements of old wine that predate the 50's. One of the longest continuous records is probably that of the Geological Survey of Canada (most recent publication by R. McNeely). They have measured C14 in maple leaves from the Gatineau every year since 1961., so have a very complete picture of the bomb pulse and its decline. Tree ring studies are probably the best source of earlier cosmogenic input. Gwen Milton ========================================================================= Date: Fri, 30 Jun 1995 10:13:57 -0700 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Mark Hall Subject: Re: Forwarded message This message was originally on arch-theory so I'm forwarding it to this list: Hello listmembers, As a courtesy, I am summarizing replies to my query. About a week ago I posted this (implicit) query to the list: >I am interested in references to the theory, methods, or actual practice >of comparing 14C histograms. My goal is to determine where on the >calendar scale two 14C histograms are significantly different and where >the differences between them are insignificant. One reply requested that I forward substantive replies. Another invited me to lunch in August! There were no references to the theory, methods, or actual practice of comparing 14C histograms. This fits well with my understanding of what I've been able to read--this is not something that has been worked out for archaeology. Many thanks for this list. It lessens the isolation of working on a small island in the middle of the ocean. Aloha,Tom tdye@mail.pixi.com ========================================================================= Date: Fri, 30 Jun 1995 15:33:32 -0700 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: David Sewell Subject: Dead Sea Mammoths and Geosciences (AMS) faculty position The next issue of RADIOCARBON will feature articles on dating the Dead Sea Scrolls and on the dwarf mammoths of Wrangel Island (north of Siberia) that survived until around 2000 BC. The table of contents and abstracts are now available on our WWW server: http://packrat.aml.arizona.edu/ Also, you'll find a copy there of an announcement of a faculty position at Purdue University with the PRIME Lab and the Department of Earth and Atmospheric Sciences, open at any rank, for someone with experience in AMS dating. I can e-mail a text copy of the announcement to anyone who doesn't have access to a WWW browser. (The announcement will also appear in RADIOCARBON.) -- David Sewell, Assistant Editor RADIOCARBON: An International Journal of Cosmogenic Isotope Research Department of Geosciences, University of Arizona 4717 E. Ft. Lowell Rd., Tucson, Arizona 85712 USA Telephone: 1-520-881-0857 Fax: 1-520-881-0554 General e-mail address: c14@packrat.aml.arizona.edu,