Geological Survey of Canada Radiocarbon Dates Xix
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GEOLOGICAL SURVEY OF CANADA COMMISSION GEOLOGIQUE DU CANADA PAPER 79-7 GEOLOGICAL SURVEY OF CANADA RADIOCARBON DATES XIX J.A. LOWDON W. BLAKE, JR. Energy, Mines and Energie, Mines et 1+ Resources Canada Ressources Canada 1979 GEOLOGICAL SURVEY PAPER 79-7 GEOLOGICAL SURVEY OF CANADA RADIOCARBON DATES XIX J.A. LOWDON W. BLAKE, JR. 1979 © Minist er of Supply and Services Canada 1979 Ava il able in Canada through author ized bookstore agents a nd other bookstores or by mai l fro m Canad ian Government Publishing Centre Supply and Services Canada Hull, Quebec, Canada K 1:\ OS9 and from GeoJogica l Survey of C":anarla 601 Booth St rf>et Ottawa, Canada K I A OE 8 f\ deposit copy of t his publiration is also avaiJ abJe for reference in public Ji brcl r ies across Cana da Cat. No. M44-79/7E Canada: $4.00 ISB N - 0-660- 1061 8-'3 Othe r rountr ies: $4.80 Price subject to c:hange without not ire Q,'iginal manuscript .<ubm itted: 1979 - 12 - 13 '\pproved for publication: 1980 - 01 - 28 CONTENTS 1 Abstract/Resume 1 Introduction 3 Acknow ledgments 3 Geological samples 3 Mid-Atlantic Ridge 3 Labrador Sea 4 Eastern Canada 4 Newfoundland 4 Labrador 4 Nova Scot ia 5 New Brunswick 5 Quebec 12 Ontario 14 Western Canada 14 Manitoba 16 Alberta 20 British Columbia 28 Northern Canada, Mainland and Offshore Islands 28 Yukon Territory 32 Northwest Territories 37 Northern Canada, Arctic Archipelago 37 Baffin Island 39 Somerset Island 41 Russell Island 41 Lowther Island 41 Bathurst Island 41 Cornwallis Island 42 Coburg Island 42 Ellesmere Island 46 Melville Island/Byam Channel 48 United States of America 48 Maine 49 New York 49 Wisconsin 49 Alaska 50 Archeological samples 50 Northern Canada, Mainland and Offshore Islands 50 Yukon Territory 51 References 58 Index Tables 1. Background for periods used for age calculations, September 6, 1978 to October 3, 1979 2. Standard for periods used for age calculations, September 6, 1978 to October 3, 1979 2 3. Number of counts used to deter mine average background and standard counting rates 2 4. Number of different background and standard age preparations used for counting The present date list, GSC XIX, is the eighth to be published directly in the Geological Survey's Paper ser ies. Lists prior to GSC XII were published first in the journal Radiocarbon and were reprinted as GSC Papers. The lists through 1967 (GSC VI) were given new pagination, whereas lists VJl to XI (1968 to 1971) were reprinted with the same pagination. GEOLOGICAL SURVEY OF CANADA RADIOCARBON DATES XIX Abstract This list includes 289 radiocarbon age determinations on 271 geological samples made by the Radiocarbon Dating Laboratory. They are on sa mples {rom various areas as (ollows: "'lid- At/antic Ridge (2); Labrador Sea (7); New{oundland (l); Labrador (2); Nova Scotia (1); New Brunswick (3); Quebec (42); Ontario (12); Manitoba (9); Alberta (20); British Columbia (51); Yukon Territory (24); Northwest Territorie s, Mainland (31); Northwest Territories, Arctic Archipelago (70); .Haine (.9); :'Iew York (2); Wisconsin (1); Alaska (2). Age determinations on archeological samples are as {ollo ws: Yukon Territory (2). Details o{ background and standard {or the 2 Land 5 L counters during the period {rom September 6, 19 78 to October 3, 1979 are summarized in Tables 1 and 2; Table 3 gives the number o{ counts used to determine the average background and standard counting rate0; and Table 4 lists the number o{ di{{erent background and standard gas preparations used (or counting. Resume Ce rapport presente les resultats de 28.9 datations e{fectuees sur 271 echantillons gpologiques par Ie Laboratorie de datation au radiocarbone. Ces echantillons proviennent des regions suivante.s: La dorsale medio-Atlantique (2); La mer du Labrador (7); He de Terre- Neuve (1); Labrador (2); Nouvelle-Ecosse (1); Nouveau-Brunswick (3); Quebec (42); Ontario (12); Manitoba (.9); Alberta (20); Colombie-Britannique (51); Yukon (24); Terr'itoires du Nord-Ouest, continent (31); Territoires du Nord-Ouest. archipel Arctique (70); Maine (9); New York (2); Wisconsin (1); Alaska (2); Les datations e{fectuees sur echantillons archeologiques sont: Yukon (2). Les valeurs de mouvement pr-opre et de l'etalonnage des compteurs 2 L et 5 L, pour la periode allant du 6 septembre 1.97 8 au 3 octobre 1979, sont presentees dans les tableaux 1 et 2; Ie tableau 3 donne Ie nombre de coups utilises pour determiner la moyenne des taux d'impulsions du mouvement propre et de I'etalonnage ; et. Ie tableau 4 donne Ie nombre de preparations de gaz pour Ie mouve ment propre et pour I'etalonnage utilisfes pour Ie comptage. INTRODUCTION I rates were within statistica l limits. In early JanudrY all 23 cosmic ray guard tubes in the rounter shielding system During the period covered by this introduction were replaced. A result of this can be seen (Table 1) in the (September 1978 through September 1979) both the 2 L lower backgrounds attained, especiall y in the 5 L counter. counter (Dyck and Fy les, 1962) and the 5 L counter (Dyck et aL, 1965) were operated for the entire 13 months. Table 3 lists the number of daily rounts used to The 2 L counter was operated at 2 atm and the 5 L at I atm. determine the average barkground '-Ind standard counting rates that were utilized for age calculations during the Average background and standard counting rates for the periods listed. Table 4 lists the number of different periods used for computerized age calculations are shown in background and standard gas preparations used for counting Tables 1 and 2, respectively. On a period basis, aJJ counting during the same periods. Table 1 Table 2 Background (e/m)* for Periods Used for Age Calculations Standard, No *, (elm) for Periods Lsed for Age Calrulations September 6, 1978 to October 3, 1979 September 6, 1978 to October 3, 1979 PERIOD 2 L COUNTER 5 L COUNTER PERIOD 2 L COUNTER 5 L COU ~TER (2 atm) (I atm) (2 atm) (l a tm) September 1978 1.233 ± 0.020 2.375 ± 0.027 September 1978 18.028 ± 0.094 28.003 ± 0.118 October 1.218 ± 0.019 2.465 ± 0.036 October 17.925 ± 0.094 27.968 ± 0.122 November 1.260 ± 0.023 2.547 ± 0.047 November 18.044 ± 0.149 27.972 ± 0.129 December 1.294 ± 0.020 2.659 ± 0.028 December 17.820 ± 0.098 27.953 ± 0.154 January 8 - 1.251 ± 0.044 2.282 ± 0.032 January 8 - 17.701 ± 0.122 27.918 ± 0.125 February 14, 1979 February 14, 1979 February 14 - 1.253 ± 0.026 2.308 ± 0.022 February 14 - 17.723 ± 0.095 27.886 1: 0.118 March 27 March 27 April 1.219 ± 0.021 2.307 ± 0.046 April 17.725 ± 0.096 28.078 ± 0.127 'vlay 1.267 ± 0.033 2.272 ± 0.039 May 17.629 ± 0.097 27.782 ± 0.121 June 1.243 ± 0.047 2.307 ± 0.027 June 17.661 ± 0.105 27.7 59 ± 0.122 July 1.246 ± 0.021 2.255 ± 0.025 Jul y 17.609 ± 0.098 27.965 ± 0.116 August 1.269 ± 0.030 2.280 ± 0.026 August 17.627 ± 0.098 27.903 ± 0.1 18 September 1.270 ± 0.023 2.264 ± 0.043 September 17.437 ± 0.120 27.90 I ± 0.188 *c/m = counts per minute *No = 0.95 x net counting rate of t he NBS oxalic acid standard I Prepared by J.A. Lowdon who operates the laboratory. The date list has been compiled by W. Blake, Jr. from descriptions of samples and interpre tations of age determinations by the coJ1ectors and submitters. Table 3 Number of Counts Used to Determine Average Background and Standard Counting Rates for Periods Listed ,---- PERIOD 2 L 5 L 2 L 5 L BACKGROUND BACKGROUND STANDARD STANDARD September 1978 4 4 3 3 October 4 4 3 3 November 4 4 3 3 December 4 4 3 3 January 8 - February 14, 1979 5 5 3 3 February 14 - March 27 5 5 3 3 April 4 4 3 3 May 4 4 3 3 June 4 4 3 3 July 4 4 3 3 August 4 5 3 3 September 3 4 3 3 Table 4 Number of Different Background and Standard Gas Preparations Used for Counting for Periods Listed PERIOD 2 L 5L 2 L 5L BACKGROUND BACKGROUND STANDARD STANDARD September 1978 2 2 2 2 October 2 2 2 2 November 2 2 2 2 December 2 2 2 2 January 8 - February 14, 1979 2 2 2 2 February 14 - March 27 3 3 2 2 April 2 2 2 2 May 3 2 2 2 June 2 2 2 2 July 2 3 2 2 August 3 3 2 2 September 2 2 2 2 Age calculations are carried out by a CDC Cyber 70 standard, the "normal" values used for correction 13 Series/Model 74 computer. Calculations are based on a 14C are 8 C = -25.0 '100 for wood, other terrestrial organic half-life of 5568 ± 30 years and 0.95 of the activity of the materials, and bones (terrestrial and marine), and 0.0 %0 for NBS oxalic acid standard. Ages are quoted in radiocarbon marine shells. All determinations were made on aliquots of years before present (B.P.) where "present" is taken to be the same sample gas used for age determination. Since 1975 1950.