Radiocarbon Dating Of Soils Research Articles

Falling into Vínland

Two interwoven topics are dealt with, firstly a new interpretation of the Icelandic Sagas and historical written sources on the Viking age voyages to North America, leading to a theory on the location of Vínland, and secondly an archaeological survey of deer hunting pitfalls in Newfoundland, which were possibly dug by the Nordic voyagers a millenium ago. According the theory of the article, Vínland is the modern day Newfoundland, and the Straumfjord of the sagas, where Thorfi nn Karlsefni and Gudríd Thorbjarnardóttir attempted settlement could be Sop’s Arm in White Bay on the North coast of Newfoundland. The system of pitfalls that was surveyed and excavated is close to Sop’s Arm. The pitfalls form an 82 metre long system that lies in an almost straight line. Individual pits are now 1.5–2.3 metres deep and 7–10 metres long. Two pitfalls were excavated by taking a section into them. Attempted radiocarbon dating of soil from two pitfalls was inconclusive. Considerable soil thickening of 55–110 centimetres since the pitfall construction was observed.

1. Introduction

Two interwoven topics are dealt with, firstly a new interpretation of the Icelandic Sagas and historical written sources on the Viking age voyages to North America, leading to a theory on the location of Vínland, and secondly an archaeological survey of deer hunting pitfalls in Newfoundland, which were possibly dug by the Nordic voyagers a millenium ago. According the theory of the article, Vínland is the modern day Newfoundland, and the Straumfjord of the sagas, where Thorfinn Karlsefni and Gudríd Thorbjarnardóttir attempted settlement could be Sop’s Arm in White Bay on the North coast of Newfoundland. The system of pitfalls that was surveyed and excavated is close to Sop’s Arm. The pitfalls form an 82 metre long system that lies in an almost straight line. Individual pits are now 1.5–2.3 metres deep and 7–10 metres long. Two pitfalls were excavated by taking a section into them. Attempted radiocarbon dating of soil from two pitfalls was inconclusive. Considerable soil thickening of 55–110 centimetres since the pitfall construction was observed.

Low temperature (LT) combustion of sediments does not necessarily provide accurate radiocarbon ages for site chronology

Radiocarbon dating of soils and sediments is notoriously problematic for the purposes of dating a specific event due to their heterogeneous mix of multiple organic fractions, each of which may have a different radiocarbon age. Numerous studies have failed to agree on which sedimentary fraction or radiocarbon pre-treatment method, if any, provides the closest agreement between the age of a sedimentary fraction and that of associated plant macrofossils or charcoal. We tested the stepped-combustion method of McGeehin et al. (2001), as well as standard radiocarbon humin and humic extraction techniques, using samples from a chronologically well-constrained perennially-frozen site at Quartz Creek, Yukon Territory, Canada. The ages in closest agreement with associated radiocarbon-dated plant macrofossils and with the overlying Dawson tephra were given by the humic and humin fractions, but even these were still older than the macrofossil ages by up to 4195 ± 260 radiocarbon years. The low temperature (LT) humin method recommended by McGeehin et al. (2001) yielded ages older than the macrofossils by up to nearly 4425 ± 240 radiocarbon years. These fractions, while still providing information on the mobility and potential residence times of carbon in soils and sediments, should not be relied upon to provide consistently accurate site chronologies.

Problems in Radiocarbon Dating of Soils

We discuss our progress in three principal applications of 14C dating of recent and fossil soils: 1) new methods; 2) problems of interpreting 14C soil data (e.g.,14C age of soils, age of soils, duration of humus formation, rate of carbon cycling); and 3) 14C analysis of soil organic matter (OM) in pedology and paleogeography (e.g., soil genesis and evolution, humus formation and OM metamorphosis, geochronology and stratigraphy of Late Pleistocene and Holocene sediments). We suggest exploring the above issues in the analysis of each 14C profile in conjunction with paleogeographical data, and by simulation of the carbon cycle in each type of profile.

Radiocarbon dating of soils, a review

Radiocarbon‐Datierung von Böden ‐ ein ÜberblickDie Verwendung der Radiokohlenstoff‐Datierungsmethode für bodenkundliche Zwecke wird in chronologischer Abfolge der Hauptzielrichtungen zusammenfassend dargestellt. Die dabei erkennbaren Hauptphasen und Schwerpunkte dienen als Gliederung. Am Anfang stand die Datierung von Holzkohle und begrabenen Paläoböden sowie der Versuch, einige wenige rezente Bodenbildungen auf der Basis extrahierter Huminsäuren anzugehen. Die folgende Kontroverse in bezug auf die Möglichkeiten und Grenzen der Datierung von Bodenkohlenstoff aus dem Bereich der rezenten intakten Biodynamik löste eine intensive Suche aus nach der günstigsten C‐Fraktion, gegebenenfalls nach dem Vorhandensein biologisch inerten Kohlenstoffs innerhalb des organischen C‐Pools. Heranziehung der 14C‐Datierungsmethode für bodengenetische Aufgaben führte zu Profildatierungen und zur Ermittlung der Alters‐Tiefen‐Interdependenz. Δ13C/12C‐Messungen erlaubten Herkunftsbestimmungen des Kohlenstoffs aus verschiedenen photosynthetischen Mechanismen, aus lithogenen oder biogenen C‐Reservoiren. Die schwierige Aufgabe der Erarbeitung von Systemen zur Korrektur der Verjüngung in rezenten Böden stößt auf die Notwendigkeit der Verwendung von Simulationsmodellen.