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Miami Circle - Artifacts - Radiocarbon Dates
Radiocarbon Dates
University of Houston archaeologist Randolph Widmer obtained 18 radiocarbon dates from clam shells recovered from various contexts in the 2000 field school excavations at the Miami Circle. Many of these shell samples were removed from cut hole features. Widmer combined these with earlier radiocarbon dates and proposed five prehistoric chronological phases for the site. The dates confirm that the site deposits are primarily from around 750 B.C. to A.D. 550, called by archaeologists the Glades I early period. The major break in dates comes between Widmer’s Phases IV and V, with the last phase representing a much later occupation around A.D. 1330-1680.
Radiocarbon dates from the Miami Ciricle at Brickell Poin site | |||||||
---|---|---|---|---|---|---|---|
OP# | FS# | Lab#(Beta-) | Material | Context | Conventional Radocarbon Age | 2 Sigma Calibrated Age | Phase |
3 | 558 | 166858 | Lucina Shell | Cut-hole | 2770 +/- 70 BP | Cal 760 - 370 BC | I |
3 | 343 | 146939 | Lucina Shell | Cut-hole | 2720 +/- 70 BP | Cal 740 - 340 BC | I |
3 | 395 | 166850 | Lucina Shell | Cut-hole | 2720 +/- 70 BP | Cal 740 - 370 BC | I |
3 | 274 | 146938 | Lucina Shell | Cut-hole | 2710 +/- 70 BP | Cal 730 - 340 BC | I |
SHC1 | 690 | 02452 | Charcoal | ? | 2350 +/- 50 BP2 | Cal 520 - 370 BC | I |
3 | 395 | Lucina Shell | Cut-hole | 2650 +/- 100 BP3 | Cal 500 - 300 BC | II | |
SHC | 700D | 1675 | Lucina Shell | ? | 2700 +/- 110 BP | Cal 760 - 170 BP | II |
3 | 355 | 146940 | Lucina Shell | Cut-hole | 2600 +/- 40 BP | Cal 400 - 230 BC | II |
3 | 395 | 146941 | Lucina Shell | Cut-Shell | 2570 +/- 70 BP | Cal 400 - 230 BC | II |
3 | 434 | 166851 | Lucina Shell | Cut-hole | 2570 +/- 70 BP | Cal 410 - 135 BC | II |
3 | 493 | 166856 | Lucina shell | Cut-hole | 2560 +/- 60 BP | Cal 400 - 150 BC | II |
3 | 778 | 165684 | Lucina Shell | Cut-hole | Cal 2580 +/- 60 BP | Cal 400 - 160 BC | II |
3 | 883 | 165685 | Lucina shell | Basin | 2520 +/- 70 BP | Cal 350 - 50 BC | II |
3 | 615 | 165681 | Lucina shell | Cut-hole | 2470 +/- 60 BP | Cal 350 - 30 BP | II |
3 | 529 | 166857 | Lucina shell | Cut-hole | 2460 +/- 70 BP | Cal 360 BC-AD 10 | II |
3 | 685 | 165682 | Lucina shell | Cut-hole | 2390 +/- 70 BP | Cal 160 BC-AD 10 | III |
3 | 732 | 165683 | Lucina shell | Cut-hole | 2280 +/- 80 BP | Cal 150 BC-AD 240 | III |
3 | 481 | 166854 | Lucina shell | Cut-hole | 2270 +/- 70 BP | Cal 100 BC-AD 240 | III |
3 | 487 | 166855 | Lucina shell | Cut-hole | 2770 +/- 70 BP | Cal 100 BC-AD 240 | III |
SHC | 689 | 02451 | Charcoal | ? | 2080 +/- 50 BP | Cal 200 BC-AD 30 | III |
1 | 514 | 128477 | charcoal | ? | 1950 +/- 150 BP | Cal 365 BC-AD 415 | III |
1 | 515 | 128478 | charcoal | ? | 1920 +/- 70 BP | Cal 45 BC-AD 245 | III |
3 | 473 | 166853 | Lucina shell | Cut-hole | 2020 +/- 70 BP | Cal AD 180-530 | IV |
1 | 807-B | 134546 | bone collagen sea turtle bone | Midden | 2040 +/- 40 BP | Cal AD 250-440 | IV |
SHC | 700+ | 1674 | shell columnella | ? | 1980 +/- 70 BP | Cal AD 250-580 | IV |
SHC | 667 | 02449 | charcoal | ? | 1710 +/- 60 BP | Cal AD 250-580 | IV |
1 | 585-A | 134544 | charcoal | ? | 1600 +/- 40 BP | Cal AD 390-550 | IV |
1 | 1028 | charcoal | Feature "A" turtle Carapace | 420 +/- 80 BP | Cal AD 1330-1650 | V | |
1 | 495 | bone collagen | Feature 218 Dolphin Skull | 690 +/- 40 BP | Cal AD 1550-1680 | V | |
1 | 519 | 134544 | bone collagen | Feature 234 Shark Interment | 670 +/- 30 BP | Cal AD 1560-1680 | V |
1 SHC dates from Carr and Ricisak 2000:267, Table 1, OP#1 dates from Carr and Ricisak 2000:282, Table 2). 2 SHC FS# 690 has an early appearing date range due to flatness in the calibration curve at this point. 3 This date represents the average of two combined C14 dates on the same sample. |