Table 1. Location, basal date, and areal carbon mass of peat cores located in the Hudson Bay Lowlands, Canada (HBL), sorted by latitude. All conventional 14 C dates were re-calibrated with the IntCal09 calibration curve 25. New HBL basal peat dates (n=33) contributed by the authors, appear in bold. Note: *Basal peat depth not identified in reference. **Carbon content determined via loss-on-ignition, at a level of 48 % carbon. ***Areal carbon mass determined by direct measurement of complete peat profiles (n=38), including samples (N) 10, 12, 40-44, 52-62, 64-66, 68-71, 83-86, 89-92, 101, 102, 106, 128. If peat physical data were not available (n=62), total carbon mass was estimated using a regression model (see methods). N 3 Squirrel R 50.07-83.88 173 278 GSC-6321 basal woody peat 3010 ± 60 3210 3010-3360 68 (1) 7 Harricana R 50.70-79.33 59 276 Qu-498 wood base of peat 4200 ± 120 4720 4420-5210 88 (2) 8 Birthday R 50.70-79.33 59 218 Y-1164 basal peat 4110 ± 100 4640 4320-4860 87 (3) 9 Birthday R 50.72-79.33 50 200 GSC-1493 basal peat 3920 ± 130 4350 3980-4810 83 (4) 10 KR3A** 50.74-84.60 123 271 UGAMS-12713 wood fragments 6020 ± 30 6860 6760-6950 126 Current Study 12 PL101 50.94-80.33 45 264 UGAMS-12711 2840 ± 30 2950 2870-3060 109 Current Study 13 Old Man bog 51.03-84.53 97 420 XXX-06b basal peat 5980 ± 100 6830 6570-7160 115 (5) 14 Oldman bog-8502 51.07-84.50 99 445 Beta-42381 basal peat 5920 ± 90 6750 6500-6960 114 (6) 15 Jaab L site 51.15-83.05 108 353 WAT-2571 basal peat 5560 ± 110 6360 6030-6640 109 (7) 17 Sesi M. SWF-8506A 51.23-83.03 102 149 Beta-54594 basal peat 5200 ± 60 5970 5760-6180 104 (6) 18 Sesi-bog-9204 51.25-83.33 90 220 Beta-64909 basal peat 5220 ± 90 6000 5750-6260 104 (6) 19 Sesi-bog-INT-9205 51.27-83.30 86 234 Beta-66732 basal peat 5260 ± 70 6050 5910-6260 105 (6) 20 Rupert R 51.36-78.43 46 116 GSC-5018 basal peat 5370 ± 70 6150 5960-6290 106 (8) 21 Rupert R 51.36-78.43 46 184 GSC-5019 basal peat 5830 ± 70 6640 6450-6790 112 (8) 22 Rupert R 51.37-78.43 46 187 GSC-5016 basal peat 5350 ± 60 6130 5990-6280 106 (8) 23 Rupert R 51.37-77.75 119 300 Qu-494 wood base of peat 5920 ± 100 6750 6490-7000 114 (2) 24 Rupert R 51.37-77.75 119 301 Qu-493 basal peat 5020 ± 100 5770 5590-5990 101 (9) 25 Albany Forks 51.38-84.80 162 412 GSC-831 basal peat 7140 ± 170 7970 7670-8320 129 (10)
26 Cheepay SFen-9211 51.38-83.37 80 127 Beta-64920 basal peat 4550 ± 70 5190 4970-5460 94 (6) 27 Cheepay bog-9212 51.38-83.37 80 127 Beta-66736 basal peat 3700 ± 70 4040 3850-4240 79 (6) 28 Albany R-8501 51.42-83.58 60 264 Beta-44537 basal peat 4810 ± 70 5530 5320-5660 98 (6) 29 Cheepay SFen-9213 51.42-83.37 81 104 Beta-64921 basal peat 3910 ± 80 4340 4090-4570 83 (6) 30 Albany Forks 51.42-84.80 162 450 GSC-885 basal peat 5820 ± 150 6640 6300-6980 112 (10) 31 Coastal fen site 51.47-80.62 9 81 WAT-2541 basal peat 1090 ± 70 1010 800-1180 40 (7) 32 Carling L site 51.50-81.67 68 258 WAT-2543 basal peat 4110 ± 70 4640 4440-4830 87 (7) 33 Interior fen site 51.51-81.88 72 125 WAT-2542 basal peat 1960 ± 70 1910 1730-2110 52 (7) 34 Kinosheo L, 300 51.55-81.83 68 98 WAT-2549 basal peat 2580 ± 80 2630 2370-2850 61 (7) 35 Kinosheo L, 100 51.55-81.83 68 98 WAT-2554 basal peat 2870 ± 80 3010 2790-3240 66 (7) 36 Kinosheo L, 200 51.55-81.83 68 138 WAT-2556 basal peat 3450 ± 70 3720 3490-3900 75 (7) 37 Kinosheo L, 300 51.55-81.83 68 218 WAT-2557 basal peat 3910 ± 70 4340 4100-4520 83 (7) 38 Kinosheo L, 390 51.55-81.83 68 265 WAT-2572 basal peat 4110 ± 80 4640 4440-4830 87 (7) 39 Kinosheo L, 490 51.55-81.83 68 253 WAT-2567 basal peat 3160 ± 70 3390 3220-3560 71 (7) 40 KJ101 51.55-81.82 68 297 UGAMS-12719 bryophyte 4100 ± 25 4610 4520-4810 130 Current Study 41 Kinosheo L Bog** 51.55-81.81 68 265 TO-4318 wood near basal 4000 ± 80 4480 4240-4810 85 (11) 42 KJ4-3 51.59-81.78 66 131 UGAMS-12717 wood fragments 3630 ± 25 3940 3870-4070 71 Current Study 43 KJ3-3 51.59-81.79 65 176 44 KJ2-3 51.59-81.76 65 246 97825 97824 wood + herb stems wood + herb stems 4170 ± 20 4720 4620-4830 80 Current Study 4130 ± 25 4860 4840-4960 99 Current Study 45 Sesi M SFen-8505A 51.62-82.28 69 166 Beta-53064 basal peat 5370 ± 80 6150 5950-6300 106 (6) 46 Belek L bog-8507a 51.62-82.28 69 236 Beta-54598 basal peat 3960 ± 60 4420 4180-4780 84 (6)
47 Belec L Int 9210A 51.62-82.28 69 98 Beta-66733 basal peat 4010 ± 80 4500 4240-4810 85 (6) 48 Belec L-fen-9210B 51.62-82.28 69 109 Beta-66735 basal peat 3840 ± 70 4250 4000-4430 82 (6) 49 Wabassie bog-9214 51.72-83.63 75 209 Beta-64925 basal peat 4500 ± 90 5140 4870-5450 93 (6) 50 Blackbear-8508A 51.72-83.23 62 223 Beta-45905 basal peat 3730 ± 50 4080 3930-4240 80 (6) 51 Albany R 52.25-81.58 3 96 WAT-1504 basal peat 1350 ± 70 1270 1090-1390 44 (1) 52 D001 52.67-84.02 92 231 Beta-310877 bulk peat 5240 ± 30 5980 5920-6180 102 Current Study 53 D002 52.71-84.00 91 219 Beta-310878 bulk peat 5080 ± 30 5810 5750-5910 83 Current Study 54 D003 52.76-84.14 92 223 Beta-310879 bulk peat 5100 ± 30 5810 5750-5920 80 Current Study 55 D200 52.62-84.12 118 240 Beta-310880 bulk peat 5420 ± 30 6240 6190-6290 84 Current Study 56 D201 52.72-84.25 104 201 Beta-310881 bulk peat 4400 ± 30 4960 4870-5210 106 Current Study 57 D202 52.71-84.32 105 215 Beta-310882 bulk peat 5060 ± 30 5820 5740-5900 99 Current Study 58 D204 52.54-84.58 143 129 Beta-310883 bulk peat 2900 ± 30 3740 2950-3160 64 Current Study 59 D206 52.65-84.58 142 257 Beta-310884 bulk peat 6300 ± 30 7220 7160-7290 105 Current Study 60 VM4-5 52.70-84.18 103 286 UGAMS-11673 wood fragment 5530 ± 25 6320 6290-6400 108 Current Study 61 VM4-3 52.71-84.18 103 304 Beta-281004 conifer fragments 5890 ± 40 6710 6570-6580 122 (12) 62 VM4-1 52.71-84.19 105 311 UGAMS-12718 needles; wood 5550 ± 25 6340 6300-6400 126 Current Study 63 MS15 R2 52.71-84.17 102 254 94010 wood fragements 5745 ± 20 5640 6480-6630 100 Current Study 64 VM3-3 52.71-84.17 102 242 Beta-281777 conifer needles 5640 ± 40 6420 6320-6490 104 (13) 65 VM3-2 52.71-84.17 102 262 UGAMS-12716 wood fragments 5620 ± 25 6400 6310-6450 127 Current Study 66 VM3-5 52.71-84.17 102 232 UGAMS-11672 wood fragments 5750 ± 25 6550 6480-6640 139 Current Study 67 TS01 52.72-83.94 86 218 94011 seeds 5140 ± 20 5910 5770-5940 103 Current Study
68 VM1-3 52.72-83.94 86 210 UGAMS-12715 69 VM2-1 52.72-83.94 86 211 UGAMS-12710 herbaceous 4390 ± 20 4940 4870-5040 98 Current Study 4470 ± 25 5180 4980-5290 85 Current Study 70 VM2-3 52.72-83.94 86 207 UGAMS-11426 wood 4100 ± 30 4610 4450-4810 90 Current Study 71 VM2-5 52.72-83.94 86 180 UGAMS-11674 wood fragments 4980 ± 25 5700 5640-5850 84 Current Study 72 IB wetland 52.73-77.77 88 188 Beta-254946 basal peat 4920 ± 40 5650 5590-5730 100 (14) 73 OFL wetland 52.78-77.51 102 207 Beta-251799 basal peat 4970 ± 40 5700 5600-5880 100 (14) 74 BF 52.73-78.50 50 72 Beta-251816 Picea needles, conifer bark 110 ± 40 120 (-4)-270 29 (14) 78 Attawapaskat 53.12-85.42 117 198 GSC-31 basal peat 5670 ± 110 6470 6280-6730 110 (15) 79 Attawapiskat R 53.13-85.30 108 128 GrN-1925 basal peat 4940 ± 80 5690 5490-5900 100 (16) 80 ML201 54.24-87.74 143 235 UGAMS-12712 7350 ± 30 8160 8040-8290 108 Current Study 81 Hawley L 54.57-84.67 137 292 GSC(24)7 basal peat 5580 ± 150 6380 6000-6710 109 (17) 82 Palsa bog 54.57-84.63 113 89 BGS-6 basal peat 1897 ± 63 1840 1700-1990 51 (18) 83 HL02 54.61-84.60 85 230 UGAMS-11422 84 HL03 54.68-84.60 99 269 UGAMS-11423 4020 ± 25 4480 4420-4570 92 Current Study 2700 ± 25 3550 3290-3880 122 Current Study 85 HL04A(West) 54.75-84.53 89 93 UGAMS-11424 wood fragments 4960 ± 30 5685 5610-5740 73 Current Study 86 HL04B(East) 54.75-84.50 97 105 UGAMS-11251 wood 4400 ± 25 4960 4870-5040 73 Current Study 87 C Henrietta Maria 55.00-82.33 2 122 GSC-231 basal peat 1210 ± 130 1130 800-1360 42 (17) 88 Shagamu R 027a* 55.05-86.75 126 -- BGS-702 basal peat 4020 ± 100 4510 4240-4830 85 (19) 89 PB3-5 55.23-84.33 10 44 UGAMS-11421 stems 610 ± 20 600 550-650 22 Current Study 90 PB-SF-5 55.23-84.30 11 24 UGAMS-11670 wood fragments 1340 ± 20 1280 1190-1300 22 Current Study 91 PB2-5 55.23-84.33 10 45 UGAMS-11420 stems F 14 C=1.01 ± 0.003 Modern -- 23 Current Study
92 PB1-5 55.24-84.32 9 42 UGAMS-12714 stems 610 ± 25 600 550-650 21 Current Study 93 Shagamu R 208a * 55.35-86.70 105 -- BGS-708 basal peat 5600 ± 140 6400 6020-6730 109 (19) 94 Shagamu R 62Ca * 55.60-86.65 32 -- BGS-822 basal peat 2350 ± 100 2420 2150-2710 58 (19) 95 Shagamu R 62Ba * 55.65-86.60 23 -- BGS-709 basal peat 2060 ± 100 2040 1820-2310 54 (19) 96 Shagamu R 62Aa * 55.70-86.51 4 -- BGS-820 basal peat 800 ± 100 740 560-930 37 (19) 97 Charlebois 56.67-94.08 117 240 GSC-2760 basal peat 6280 ± 80 7200 6990-7420 120 (20) 99 Thibaudeau Stn 57.08-94.16 122 155 GSC-5213 basal peat 6240 ± 80 7150 6940-7410 119 (18) 100 Silcox 57.17-94.24 142 73 GSC-5245 basal peat 3120 ± 60 3340 3170-3470 70 (21) 101 Herchmer Bog ** 57.38-94.20 106 167 AECV-1715C basal peat 5970 ± 90 6810 6560-7150 148 (22) 102 Herchmer Fen ** 57.38-94.20 106 203 AEVC-1714 bulk peat 5580 ± 80 6373 6210-6550 105 (23) 103 Lost Moose/O'Day 57.57-94.32 113 130 GSC-5221 basal peat 4270 ± 70 4840 4580-5040 89 (21) 106 McClintock Bog ** 57.80-94.21 79 163 AECV-1718C wood 5810 ± 90 6610 6410-6840 143 (22) 108 Fletcher L 58.17-93.83 49 324 GSC-3988 basal peat 3400 ± 60 3650 3480-3830 74 (24) 123 Shagamu R 027b * 55.05-86.75 126 -- BGS-800 basal peat 5050 ± 100 5800 5600-5990 102 (19) 124 Shagamu R 208b * 55.35-86.70 105 -- BGS-801 basal peat 5270 ± 100 6060 5760-6290 105 (19) 125 Shagamu R 62Cb * 55.60-86.65 32 -- BGS-710 basal peat 2250 ± 110 2250 1950-2700 56 (19) 126 Shagamu R 62Bb * 55.65-86.60 23 -- BGS-821 basal peat 1725 ± 100 1640 1410-1870 48 (19) 127 Shagamu R 62Ab * 55.70-86.51 4 -- BGS-701 basal peat 700 ± 100 660 520-900 36 (19) 128 McLintock Fen ** 57.80-94.20 81 148 AECV-1717C basal peat 4060 ± 100 4570 4290-4840 68 (23)
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