Table 1.
Sites reportedly dated to the onset of the Younger Dryas and yielding impact markers
| Site | Basis for age estimation (14C calibration used)* | Fig. 1 group | Ref(s). |
| Abu Hureyra, Syria | 14C ages (IntCal 04) | 3a | 3, 10 |
| Arlington Canyon, CA | 14C ages (IntCal09) | 3a | 8, 10, 34 |
| Barber Creek, NC | OSL and 14C ages (IntCal09) | 3a | 3, 10 |
| Big Eddy, MO | 14C ages (IntCal04) | 3b | 3, 10 |
| Blackville, SC | OSL ages | 3a | 3, 10 |
| Blackwater Draw, NM | 14C ages (IntCal04) | 3a | 1, 3, 5, 9, 10–11 |
| Bull Creek, OK | 14C ages (IntCal09) | 3c | 7, 63–64 |
| Carolina Bays, NC and SC | OSL ages | 2a | 1, 2, 5 |
| Chobot, Alberta, Canada | No radiometric control | 1a | 2–3, 5, 10 |
| Daisy Cave, CA | 14C ages (IntCal04) | 3d | 2, 5 |
| Gainey, MI | TL and 14C ages (IntCal09) | 2a | 2–5, 10–11 |
| Kangerlussuaq, Greenland | O-isotope curve and dust stratigraphy | 2a | 13, 41 |
| Kimbel Bay, NC | OSL and 14C ages (IntCal09) | 3a | 3, 10 |
| Lake Cuitzeo, Mexico | 14C ages (IntCal04) | 3a | 3, 6, 10 |
| Lake Hind, Manitoba, Canada | 14C ages (IntCal04) | 3d | 2, 7, 10 |
| Lingen, Germany | 14C ages (IntCal09) | 2a | 3, 10 |
| Lommell, Belgium | 14C ages (IntCal04 in 2; IntCal09? in others) | 3c | 2–3, 5, 10–11 |
| Melrose, PA | OSL ages | 3a | 3, 10–11 |
| Morley, Alberta, Canada | No radiometric control | 1a | 2, 10 |
| MUM7B, Venezuela | 14C ages (IntCal04) | 2a | 12 |
| Murray Springs, AZ | 14C ages (IntCal04) | 3a | 1–3, 7, 10–11 |
| Newtonville, NJ | OSL age | 2a | 11 |
| Ommen, Netherlands | 14C ages (IntCal09?) | 3c | 3, 10 |
| Paw Paw Cove, MD | No radiometric control | 1a | 9 |
| Playa Basins, NM and TX | 14C ages (IntCal04) | 2a | 1, 4 |
| Sheridan Cave, OH | 14C ages (IntCal04) | 2a | 3, 10–11 |
| Talega, CA | 14C ages (IntCal09) | 3a | 3, 10 |
| Topper, SC | OSL and 14C ages (IntCal09) | 3a | 2–3, 9–10 |
| Wally’s Beach, Alberta, Canada | 14C ages (IntCal04) | 2a | 2, 5 |
With IntCal04 the Younger Dryas onset is put at 12.9 ± 0.1 kcal B.P.; it is 12.8 ± 0.15 kcal B.P. using IntCal09.
*
The calibration curve used (whether IntCal04 or IntCal09) and program to derive the calibrated ages (whether CALIB, OxCal, CalPal, etc.) are only occasionally specified in the sources. We were not able to otherwise identify the calibration by replication; hence, the identification of the calibration that was used is based on the best available evidence, such as when a paper appeared relative to the available calibration.