========================================================================= Date: Fri, 8 Jun 2001 14:20:29 +0100 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Philip Collins Subject: Catastrophes conference In-Reply-To: <3B096C42.81C6A69F@uni-koeln.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; CHARSET=US-ASCII Members of the list may be interested in the following conference announcement. Further details are available from Suzanne Leroy at Brunel University, UK (suzanne.leroy@brunel.ac.uk) An international conference on "Holocene environmental catastrophes and recovery" 2-7 Sept. 2002 at Brunel Univesity, west London. Co-sponsored by Brunel University, INQUA and PAGES. The four main themes are: 1 - Geological catastrophes and their impact on society e.g. megalandslides, earthquakes, tsunami, fires, volcanic eruptions 2 - Environmental causes of civilisation collapse 3 - Biological impacts on societies: extinctions, epidemies, plague, haemorrhagic fever 4 - Climatological impacts on society, e.g. historical droughts. An informal pre-conference fieldtrip is planned that will examine evidence for past environmental catastrophes in the Scottish Highlands (post-glacial large-magnitude earthquakes; glacial megafloods; Storegga-Slides tsunami event; human impacts of Icelandic volcanic catastrophes; environmental disturbances in Loch Ness). Preliminary dates for the fieldtrip are 26 to 31 August 2002. More details to follow. see for more information: http://www.brunel.ac.uk/depts/geo/Catastrophes/ contact: Prof. Suzanne A. G. Leroy, Department of Geography and Earth Sciences, Brunel University, Uxbridge, Middlesex UB8 3PH, (West London), UK. suzanne.leroy@brunel.ac.uk, direct: +44-1895-20 31 78; fax: +44-1895-20 32 17, secr: +44-1895-20 3215 http://www.brunel.ac.uk/depts/geo/newweb/peoplesub.html ----------------------------------------- Dr. Philip E.F. Collins Environmental Change Research Group Department of Geography & Earth Sciences Brunel University Uxbridge UB8 3PH United Kingdom Tel: +44 (0) 1895 274000 (Switchboard) ext 2381 Fax: +44 (0) 1895 203217 Email: philip.collins@brunel.ac.uk http://www.brunel.ac.uk/depts/geo/philsub/phil.html Please consult our website: http://www.brunel.ac.uk/depts/geo/Catastrophes/ for the conference on "Holocene environmental catastrophes and recovery", 2-7 Sept. 2002. =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. ========================================================================= Date: Mon, 18 Jun 2001 20:39:19 +0200 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Verushka Valsecchi Subject: AMS dating MIME-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 8bit Dear Colleague, Is there someone that know how many grams are needed for AMS dating? I found 1 mg but of organic carbon!! Instead I would like to know how many grams of woods and seeds! Have you any references to suggest? Is depend also to a type of wood or seeds? Thank you very much Yours sincerely Verushka Valsecchi ------------------------ Verushka Valsecchi-PhD student Department of Earth Science University of Milan ITALY =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. ========================================================================= Date: Tue, 19 Jun 2001 09:43:44 +0100 Reply-To: christopher.ramsey@archaeology-research.oxford.ac.uk Sender: Radiocarbon Mailing List From: Christopher Ramsey Subject: Re: AMS dating sample sizes In-Reply-To: MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Our WWW site: http://www.rlaha.ox.ac.uk/orau/index.htm Has a list of 'standard' sample sizes (look under 'Applications of Radiocarbon' and pick either 'Archaeological' or 'Environmental'). In practice much smaller samples can be dated but usually with a reduction in precision. Christopher Ramsey On 18 Jun 2001, at 20:39, Verushka Valsecchi wrote: > Dear Colleague, > > Is there someone that know how many grams are needed for AMS dating? I > found 1 mg but of organic carbon!! Instead I would like to know how > many grams of woods and seeds! > Have you any references to suggest? > Is depend also to a type of wood or seeds? > > Thank you very much > > Yours sincerely > Verushka Valsecchi > > ------------------------ > Verushka Valsecchi-PhD student > Department of Earth Science > University of Milan > ITALY > > ============================================================================ > To unsubscribe from this list, send the command SIGNOFF C14-L to > LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. > =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. ========================================================================= Date: Wed, 20 Jun 2001 00:21:14 +0100 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Philip Collins Subject: Dating bulk lake sediments In-Reply-To: <3B2F1ED0.16026.93069@localhost> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; CHARSET=US-ASCII Dear all, I've been musing over this for a while and thought it might be a good area for discussion... Recently I've noticed 14C dates on bulk organic-rich lake sediment sometimes being adjusted for a reservoir effect, even in apparently low carbonate sediments. In one case this adjustment was largely justified by the fact that a linear age depth model (derived apparently from a regression of the mean dates) suggested the surface sediment was several hundred years old. My first reaction was to think 'why have they done that?' as it seems packed full of assumptions, not least that accumulation was constant and also that the reservoir effect was also constant over several millennia. My second reaction was 'am I missing something important here?' - hence a few questions which will hopefully draw out some state of the art responses: 1. In the absence of 14C dates on good terrestrial macrofossils or varves, is there any way of assessing accurately and precisely whether a reservoir adjustment is valid/needed? Can different extracts (solids, humics etc) be used? 2. Is there any evidence for variations in lake 14C reservoirs over time and, if so, how quickly can the reservoir effect change and what controls it? 3. How reliable are statistically-derived age-depth models? How many times do they match up with independent dating accurately and precisely? I'm particularly interested from the point of testing hypotheses of quasi-periodic environmental (climatic) cycles and identifying abrupt change. I've got my own views on some of these, but I've spent most of my time working in dodgy fluvial and coastal contexts where it pays to be sceptical about dating, so I'm particularly interested to hear views from the lakes community. Look forward to some discussion, Phil ----------------------------------------- Dr. Philip E.F. Collins Environmental Change Research Group Department of Geography & Earth Sciences Brunel University Uxbridge UB8 3PH United Kingdom Tel: +44 (0) 1895 274000 (Switchboard) ext 2381 Fax: +44 (0) 1895 203217 Email: philip.collins@brunel.ac.uk http://www.brunel.ac.uk/depts/geo/people/philcollins.html Please consult our website: http://www.brunel.ac.uk/depts/geo/Catastrophes/ for the conference on "Holocene environmental catastrophes and recovery", 2-7 Sept. 2002. =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. ========================================================================= Date: Wed, 20 Jun 2001 17:35:27 +0200 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Bas van Geel Subject: Re: Dating bulk lake sediments In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Dear Phil, The answer on your first question could come from applying the strategy of 14C wiggle matching. During a period showing a plateau in the 14C calibration curve you might well be able to find that plateau (and the steep parts of the calibration curve before and after the plateau), but the sample BP values may be too old (as a consequence of a reservoir effect). Following this strategy we recognised and could estimate reservoir ages (which were completely unexpected) for bulk samples in raised bog material. The plateau between ca 760 and 420 cal BC was the one we could use. See Kilian, M.R., van der Plicht, J. and van Geel, B., 1995. Dating raised bogs: new aspects of AMS 14C wiggle matching, a reservoir effect and climatic change. Quaternary Science Reviews 14: 959-966. Best wishes, Bas van Geel >Dear all, > >I've been musing over this for a while and thought it might be a good area >for discussion... ........ - hence a >few questions which will hopefully draw out some state of the art >responses: > >1. In the absence of 14C dates on good terrestrial macrofossils or varves, >is there any way of assessing accurately and precisely whether a reservoir >adjustment is valid/needed? Can different extracts (solids, humics etc) be >used? ....... >Look forward to some discussion, >Phil ------------------------------------------------------------------------- PLEASE NOTE MY NEW E-MAIL ADDRESS Dr Bas van Geel E-mail: vanGeel@science.uva.nl Phone: +31 20 525 7664 Fax: +31 20 525 7832 Institute for Biodiversity and Ecosystem Dynamics (IBED) Research Group Palynology and Paleo/Actuo-ecology * Faculty of Science, Universiteit van Amsterdam Postal address: P.O. Box 94062, 1090 GB Amsterdam, The Netherlands (Visiting address: Amsterdam, Kruislaan 318, building I, room B111) *participating in Graduate School 'Centre for Geo-ecological Research' (ICG) ------------------------------------------------------------------------- =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. ========================================================================= Date: Wed, 20 Jun 2001 10:57:13 -0600 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: "Gifford H. Miller" Subject: Re: Dating bulk lake sediments In-Reply-To: Mime-Version: 1.0 Content-Type: text/enriched; charset="us-ascii" Phil: Reservoir effects in non-hardwater lakes for bulk sediment, or even isolated geochemical separates, are common, typically due to the residence time of organic matter in catchment soils. We have a growing database on paired macrofossil (or tephra)-DOC dates from high latitude lakes. At colder sites the reservoir effect is typically greatest (low primary production, slow decomposition). We have confirmed reservoir effects of over 20,000 years (I know that's hard to believe) from Arctic Canada. Typical Holocene offsets in the same area between humic acid extracts and macrofossils are 300 to 600 years, and for humins it is 600 to 1000 years or so. The offset changes systematically with time in glaciated terrain with no offset at deglaciation, increasing for the first few millennia until it reaches an apparent steady state value. In all cases we can demonstrate that the lake-waters are equilibrated with the atmosphere (living aquatic tissue has the same 14C activity as the modern atmosphere), and in one test case can show that the DOC in stream inflow and DOC in the water itself is "aged". A couple of refs on this are: Abbott, M.B. and Stafford, T.W.J., 1996. Radiocarbon geochemistry of modern and ancient arctic lake systems, Baffin Island, Canada. Quaternary Research, 45: 300-311. TimesMiller, G.H.Times, Mode, W.N., Sauer, P.E., Wolfe, A.P., Bennike, O., Forman, S.L., Short, S.K., Stafford, T.W., Jr., and Williams, K.M., 1999: Stratified interglacial lacustrine sediment from Baffin Island, Arctic Canada: Chronology and paleoenvironmental implications. Quaternary Science Reviews, 18: 789-810. Cheers, Gifford Miller >Dear all, > >I've been musing over this for a while and thought it might be a good area >for discussion... > >Recently I've noticed 14C dates on bulk organic-rich lake sediment >sometimes being adjusted for a reservoir effect, even in apparently low >carbonate sediments. In one case this adjustment was largely justified by >the fact that a linear age depth model (derived apparently from a >regression of the mean dates) suggested the surface sediment was several >hundred years old. > >My first reaction was to think 'why have they done that?' as it seems >packed full of assumptions, not least that accumulation was constant and >also that the reservoir effect was also constant over several millennia. >My second reaction was 'am I missing something important here?' - hence a >few questions which will hopefully draw out some state of the art >responses: > >1. In the absence of 14C dates on good terrestrial macrofossils or varves, >is there any way of assessing accurately and precisely whether a reservoir >adjustment is valid/needed? Can different extracts (solids, humics etc) be >used? > >2. Is there any evidence for variations in lake 14C reservoirs over time >and, if so, how quickly can the reservoir effect change and what controls >it? > >3. How reliable are statistically-derived age-depth models? How many >times do they match up with independent dating accurately and precisely? >I'm particularly interested from the point of testing hypotheses of >quasi-periodic environmental (climatic) cycles and identifying abrupt >change. > >I've got my own views on some of these, but I've spent most of my time >working in dodgy fluvial and coastal contexts where it pays to be sceptical >about dating, so I'm particularly interested to hear views from the lakes >community. > >Look forward to some discussion, > >Phil > >----------------------------------------- >Dr. Philip E.F. Collins Environmental Change Research Group >Department of Geography & Earth Sciences >Brunel University >Uxbridge UB8 3PH >United Kingdom > >Tel: +44 (0) 1895 274000 (Switchboard) ext 2381 >Fax: +44 (0) 1895 203217 >Email: philip.collins@brunel.ac.uk >http://www.brunel.ac.uk/depts/geo/people/philcollins.html > >Please consult our website: >http://www.brunel.ac.uk/depts/geo/Catastrophes/ >for the conference on "Holocene environmental catastrophes and >recovery", 2-7 Sept. 2002. > >============================================================================ >To unsubscribe from this list, send the command SIGNOFF C14-L to >LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. Gifford H. Miller INSTAAR and Geological Sciences University of Colorado Boulder CO 80309-0450 =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. ========================================================================= Date: Thu, 21 Jun 2001 10:31:54 -0700 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Emmanuelle Delque Subject: extraction of carbon with laser Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit Hello, I am looking for information concerning extraction of carbon with laser. There were experiments with Rock painting by Watchman few years ago. Does anybody knows if there is something new ? Thanks a lot Emmanuelle Delqué-Kolic Centre de Datation par le Radiocarbone Université Claude Bernard Lyon 1 40, Bd Niels Bohr 69622 VILLEURBANNE Cedex tél. 04 72 43 13 18 fax. 04 72 43 13 17 delque@cismsun.univ-lyon1.fr =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. ========================================================================= Date: Fri, 22 Jun 2001 12:15:25 +1000 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Graeme Ward Subject: Re: extraction of carbon with laser In-Reply-To: <3.0.1.16.20010621185233.2f3f0a0c@cismsun.univ-lyon1.fr> Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="=====================_8044453==_.ALT" --=====================_8044453==_.ALT Content-Type: text/plain; charset="iso-8859-1"; format=flowed Content-Transfer-Encoding: quoted-printable Alan Watchman continues to develop this technique: Alan.Watchman@jcu.edu.au At 10:31 21/06/01 -0700, you wrote: >Hello, >I am looking for information concerning extraction of carbon with laser. __________________________________________________________ Graeme K Ward (MA Otago, PhD ANU), Research Fellow Australian Institute of Aboriginal and Torres Strait Islander Studies GPO Box 553 CANBERRA 2601 Australia Telephone: +61 (02) 6246 1151 Facsimile: +61 (02) 6249 7714 (or 7310) Email: gkw@aiatsis.gov.au AIATSIS WWW site: http://www.aiatsis.gov.au Published July 2000: Advances in Dating Australian Rock-Markings, edited=20 by Graeme K. Ward and Claudio Tuniz. Archaeological Publications,=20 Melbourne. ISBN 0 958602 1 3 Published August 2000: Indigenous Cultures in an Interconnected World,=20 edited by Claire Smith & Graeme K. Ward. Allen and Unwin, St Leonards,=20 NSW. ISBN: 186448926X http://www.allen-unwin.com.au/academic/ Published December 2000 (Contributing editor): Gwion Gwion: Dulwan Mamaa.=20 Secret and sacred pathways of the Ngarinyin Aboriginal people of Australia= =20 by Ngarjno, Ungudman, Banngal, Nyawarra [Ngarinyin munnumburra], edited by= =20 J. Doring. Koenemann / K=F6nemann, Cologne. ISBN 3-890-4060-1 --=====================_8044453==_.ALT Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Alan Watchman continues to develop this technique: Alan.Watchman@jcu.edu.au

At 10:31 21/06/01 -0700, you wrote:
Hello,
I am looking for information concerning extraction of carbon with laser.


__________________________________________________________ Graeme K Ward (MA Otago, PhD ANU), Research Fellow
Australian Institute of Aboriginal and Torres Strait Islander Studies
GPO Box 553   CANBERRA   2601   Australia
Telephone: +61 (02) 6246 1151    Facsimile: +61 (02) 6249 7714 (or 7310)
Email: gkw@aiatsis.gov.au   AIATSIS WWW site: http://www.aiatsis.gov.au

Published July 2000:  Advances in Dating Australian Rock-Markings, edited by Graeme K. Ward and Claudio Tuniz.   Archaeological Publications, Melbourne.  ISBN 0 958602 1 3
Published August 2000: Indigenous Cultures in an Interconnected World, edited by Claire Smith & Graeme K. Ward.  Allen and Unwin, St Leonards, NSW.  ISBN: 186448926X
http://www.allen-unwin.com.au/academic/
Published December 2000 (Contributing editor): Gwion Gwion: Dulwan Mamaa. Secret and sacred pathways of the Ngarinyin Aboriginal people of Australia by Ngarjno, Ungudman, Banngal, Nyawarra [Ngarinyin munnumburra], edited by J. Doring.  Koenemann / K=F6nemann, Cologne.  ISBN 3-890-4060-1
 --=====================_8044453==_.ALT-- =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. ========================================================================= Date: Tue, 26 Jun 2001 15:48:40 -0500 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Michael Kaplan Subject: carbonate-cemented concretions MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Can anyone recommend articles that discuss the accuracy, or uncertainties, of 14C dating of carbonate-cemented concretions found in sediments deposited in former lakes? My area of interest, in Patagonia, is now arid. However, the region was probably wetter during glacial periods. Thanks, Mike Kaplan Department of Geology and Geophysics University of Wisconsin-Madison 1215 W. Dayton St. Madison, WI 53706 USA (608) 265 2601 http://www.geology.wisc.edu/~kaplanm/ =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. ========================================================================= Date: Wed, 27 Jun 2001 09:07:43 -0700 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: "Christopher C. Dorion" Subject: Re: carbonate-cemented concretions In-Reply-To: Mime-version: 1.0 Content-type: text/plain; charset="US-ASCII" Content-transfer-encoding: 7bit on 6/26/01 1:48 PM, Michael Kaplan at kaplanm@GEOLOGY.WISC.EDU wrote: > Can anyone recommend articles that discuss the accuracy, or uncertainties, > of 14C dating of carbonate-cemented concretions found in sediments > deposited in former lakes? My area of interest, in Patagonia, is now arid. > However, the region was probably wetter during glacial periods. > > Thanks, > Mike Kaplan Hi Mike, I recommend you apply some of the techniques we used to analyze suspect molluscs in the marine sediments of eastern Maine. First, run O-18/C-13 to check for re-equilabration with modern groundwater. Second, run XRD to check for calcite/aragonite percentages (if this is applicable). You may want to do some partial leaches or serial sampling of the conretions to check for partial re-equilabration. Chris -- Chris Dorion 79 Bennoch Road Orono, Maine 04473 E-mail: cdorion@infi.net Voice: 207 866-7806 FAX: 207 866-8663 Cellular: 207 944-4302 =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. ========================================================================= Date: Thu, 28 Jun 2001 10:13:28 +0200 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Iain Robertson Subject: bone remodelling Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8bit Dear colleagues, I'm new to the wonderful world of radiocarbon dating! I would be grateful if anyone could recommend any articles on the turnover rate of bone collagen. I had read that ten years is a good approximation, but I'm sure there must be more references out there. We're working with the femur of a roan antelope (Hippotragus equinus) that had the mis-fortune of falling down a big hole. If's of a very recent origin hence, the turnover rate becomes more important. Thanks Iain ********************************************* Dr Iain Robertson Quaternary Dating Research Unit, CSIR Environmentek, PO Box 395, 0001 Pretoria, SOUTH AFRICA. Tel + 27 12 841 2300 Fax + 27 12 349 1170 ********************************************* =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. ========================================================================= Date: Fri, 29 Jun 2001 09:56:06 +0100 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: "Suckow, Axel" Subject: AW: bone remodelling MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit Hi Ian there is a paper written by Mebus A. Geyh about human and animal tissue dating in press for the conference issue of Israel last year (his email: mebus.geyh@t-online.de). And there was an article by Eva Wild et al. with a table about forensic samples (human bones and hair) during the last conference in Groningen (Radiocarbon, Vol. 40 No. 1, 1998, pp. 273-281). Hope this helps Axel ***************************************** Dr. Axel Suckow Institut für Geowissenschaftliche Gemeinschaftsaufgaben (GGA); Institute for Joint Geoscientific Research (GGA); Geochronology and Isotope Hydrology (S3); Stilleweg 2; 30655 Hannover; Phone: +49 511 6432527; Fax: +49 511 6433665; e-mail: Axel.Suckow@GGA-Hannover.de -----Ursprüngliche Nachricht----- Von: Iain Robertson [mailto:irobertson@CSIR.CO.ZA] Gesendet am: Donnerstag, 28. Juni 2001 09:13 An: C14-L@LISTSERV.ARIZONA.EDU Betreff: bone remodelling Dear colleagues, I'm new to the wonderful world of radiocarbon dating! I would be grateful if anyone could recommend any articles on the turnover rate of bone collagen. I had read that ten years is a good approximation, but I'm sure there must be more references out there. We're working with the femur of a roan antelope (Hippotragus equinus) that had the mis-fortune of falling down a big hole. If's of a very recent origin hence, the turnover rate becomes more important. Thanks Iain ********************************************* Dr Iain Robertson Quaternary Dating Research Unit, CSIR Environmentek, PO Box 395, 0001 Pretoria, SOUTH AFRICA. Tel + 27 12 841 2300 Fax + 27 12 349 1170 ********************************************* =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU. =========================================================================== To unsubscribe from this list, send the command SIGNOFF C14-L to LISTSERV@LISTSERV.ARIZONA.EDU, or send a request to C14-L-request@LISTSERV.ARIZONA.EDU.