INTCAL98 Radiocarbon Age Calibration, 24,000–0 cal BP

Abstract

ABSTRACT. The focus of this paper is the conversion of radiocarbon ages to calibrated (cal) ages for the interval 24,000-0 cal BP (Before Present, 0 cal BP = AD 1950), based upon a sample set of dendrochronologically dated tree rings, uranium-thorium dated corals, and varve-counted marine sediment. The 14C age-cal age information, produced by many laboratories, is converted to 14C profiles and calibration curves, for the atmosphere as well as the oceans. We discuss offsets in measured 14C ages and the errors therein, regional 14C age differences, tree-coral 14C age comparisons and the time dependence of marine reservoir ages, and evaluate decadal vs. single-year 14C results. Changes in oceanic deepwater circulation, especially for the 16,000-11,000 cal BP interval, are reflected in the A14C values of INTCAL98.

Radiocarbon dating of bulk peat samples from raised bogs: non-existence of a previously reported ‘reservoir effect’?

“…1. Four sequences of conventional bulk 14 C dates from published peat cores (diamonds with 1 s error bars) were wiggle-matched against the INTCAL98 14 C calibration curve (lines show 1 s error envelope; Stuiver et al, 1998). The depicted matches are similar to those proposed by Kilian et al (1995).…”

“…Bulk samples may contain a mixture of material of different ages (above-ground remains, roots, rootlets, fungal mycelium, charcoal, transported fine organic matter, etc.). It therefore is surprising that our conventional bulk peat 14 C dates were not significantly different from AMS 14 C dates of carefully selected and cleaned above-ground plant Stuiver et al, 1998;Blaauw et al, 2003). From the same core, 5 bulk peat samples were 14 C dated (black circles; bars indicate 1 s error limits; Table 1).…”

Over 16,000 Years of Fire Frequency Determined from AMS Radiocarbon Dating of Soil Charcoal in an Alluvial Fan at Bear Flat, Northeastern British Columbia

“…No fire events are recorded for a short interval after 8500 cal BP. After 8300 cal BP, there is a considerable increase to ~10 fires/ Figure 6 Plot of combined probability distributions (calculated from IntCal 98, Stuiver et al 1998) for the last 16,000 yr of forest fires at Bear Flat, BC. The probability shown on the vertical axis is from the sum of the 14 C probability curves (Reimer et al 2004). 10 3 yr, with a peak of ~13 fires/10 3 yr at 8000 cal BP.…”

Development of the Radiocarbon Calibration Program

“…https://doi.org/10.1017/S0033822200038212 This is only likely to make a significant difference when the calibration curve errors are large and variable-as they are at the start of the Holocene. This is particularly important with the new INTCAL98 calibration curve (Stuiver et al 1998). This modification was suggested by Stephan Puchegger of Vienna (personal communication).…”