Radiocarbon calibration curves and dendrochronology as dating tools. C14 decays with a half-life of approximately 5,730 years Radiocarbon dating can measure up to about 50,000 years, becoming less accurate after ~35,000 years Calibration curves map the historical C14/C13 ratio in the atmosphere over time

Carbon-14 decays with a half-life of about 5,730 years, making radiocarbon dating useful up to ~50,000 years (less precise after 35,000). Calibration curves map historical C14/C12 atmospheric ratios, but plateaus like the Hallstatt (around 800–600 BC) create imprecision. Dendrochronology — tree-ring dating — provides independent calibration, and curves are regularly refined with new tree-ring samples of known age.

Key Facts

  • C14 decays with a half-life of approximately 5,730 years
  • Radiocarbon dating can measure up to about 50,000 years, becoming less accurate after ~35,000 years
  • Calibration curves map the historical C14/C13 ratio in the atmosphere over time
  • Radiocarbon plateaus (e.g., Hallstatt plateau around 800-600 BC) make dating in those periods imprecise
  • Dendrochronology provides independently dated tree rings used to calibrate radiocarbon curves
  • Calibration curves are updated using tree-ring samples of known age

Related site: The Great Pyramid of Giza — view location, images, and history on the Ancient Nerds map.