手法を比較

	テフロクロノロジー	放射性炭素年代測定法
分野	考古学	地球物理学
系統	Process / pipeline	Process / pipeline
提唱年	1944	1949
提唱者	Sigurdur Thorarinsson	Willard Libby
種類	Volcanic marker dating technique	Chronometric method based on ¹⁴C decay
原典	Thorarinsson, S. (1944). Tefrokronologiska studier på Island. Geografiska Annaler, 26(1-2), 1-217.	Libby, W. F. (1949). Radiocarbon dating. University of Chicago Press.
別名	tephra chronology, volcanic ash dating	¹⁴C dating, Carbon-14 dating
関連	4	3
概要	Tephrochronology is a chronometric and stratigraphic technique that uses volcanic ash layers (tephra) as time markers to date and correlate archaeological and geological deposits. Pioneered by Icelandic geologist Sigurdur Thorarinsson in 1944, it exploits the fact that large explosive volcanic eruptions deposit distinctive ash layers across vast geographic regions instantaneously in geological time. Each tephra layer serves as a chronological marker horizon that can be identified, characterized, and dated, enabling archaeologists to synchronize deposits across multiple sites.	Radiocarbon dating is a radiometric technique that determines the age of organic materials by measuring the radioactive decay of ¹⁴C (carbon-14), a rare isotope produced in the atmosphere by cosmic ray interactions. Developed by Willard Libby in 1949, radiocarbon dating became a foundational method in archaeology, paleoclimate studies, and geology, enabling dating of organic materials from the past ~50,000 years with typical precision of ±50–100 years.