Peter Ian Kuniholm

Absolute age range of the Late Cypriot IIC period on Cyprus

Extensive radiocarbon data are examined, including results from short-lived samples contemporary with use-contexts. An absolute date range for the main Late Cypriot IIC period on Cyprus, from c. 1340–1315 BC to c. 1200 BC, is proposed.

No systematic early bias to Mediterranean 14C ages: Radiocarbon measurements from tree-ring and air samples provide tight limits to age offsets

Existing data and theory do not support a recent assertion that upwelling of old carbon has led to systematically 100-300 yr too old radiocarbon ages for the Mediterranean region. Similarly, the prehistoric tree-ring record produced over 3 decades by the Aegean Dendrochronology Project is shown to provide robust, well-replicated data, contrary to a recent unfounded assertion. (super 14) C and dendrochronology provide an accurate and precise chronometric framework for the Mediterranean region.

Dating volcanic eruptions with tree-ring chemistry

Dendrochemical analyses of absolutely dated, overlapping sequences of tree rings allow identification of temporally conscribed, volcanically influenced periods of environmental change. Dendrochemistry, or the study of tree-ring elemental composition, is a promising new technique for reconstructing climate/environmental history at annual resolution. In particular, dendrochemistry may be useful for identifying periods of climatically and/or environmentally effective volcanic activity. Airborne pollution from major volcanic eruptions in the form of increased environmental acidity from sulfur dioxide can cause changes in availability and concentration of certain elements and can increase the availability of those elements in the soil, resulting in increased uptake by trees from the substrate or direct from the atmosphere. In particular, spikes, dips, or major changes in trace element concentration may be an indication of changes in soil or atmospheric chemistry (e.g., Padilla and Anderson 2002). Although there are other records of past volcanism (especially from ice-cores - e.g. Vinther et al. 2005), tree-ring based work (e.g. Salzer and Hughes 2007) offers several important advantages: first, tree-ring series are available with wide spatial coverage from most of the globe, and second, they are datable with annual and even subannual resolution on a fixed (absolute) calendar timescale (whereas even the best ice-core work has errors of several years or more beyond the last few hundred years).

Dendrochronology of submerged Bulgarian sites

During the late 1980s, 83 timber pilings off the Black Sea coast of Bulgaria at Kiten were sampled for dendrochronological research. According to the excavators, the pieces derived from house foundations associated with a now submerged Early Bronze Age habitation site. The wood, mostly oak, formed a 285-year tree-ring sequence, currently the longest Early Bronze Age oak chronology from the Balkans, with at l east four, possibly five, building phases identified. The four major phases are represented by at least 10 specimens each, and all construction episodes span a 64-year period. A limited number of specimens exhibited dates falling between these phases, suggesting that maintenance activities involving wood replacement were ongoing between phases. Nine 15-year-long ring sequences were wiggl e-matched to the decadal radiocarbon calibration curve of Stuiver and Becker. With an error of ±10 years, the resulting dates place the cutting of the trees for phase 1 at ca. 2778 BC and for the possible phase 5 at ca. 2715 BC. Kiten is only one of several submerged sites discovered by Bulgarian underwater archaeologists. In a discussion of flooding in the Black Sea basin, the submergence of a site occupied during the early 3rd mille nnium BC requires some explanation, considering that the date proposed by Ryan and Pitman for their inundation lies in the 6th millennium. An even earlier set of submerged timbers from Eneolithic Sozopol has now been dated and is here reported.

Beneath the Basilica of San Marco: New light on the origins of Venice

Abstract The origins of Venice have been of great interest to Venetians and to scholars more generally for centuries. Long shrouded in myth and legend due to the dearth of pre-ninth-century AD evidence, recent archaeological research is now illuminating how the famous city built on water began. Using high-resolution AMS dating of peach stones (pits) from below the Basilica of San Marco, the authors provide the first evidence for human activity at what is now the location of Piazza San Marco. Dating to between AD 650 and 770, this activity included canal in-filling and ground consolidation intended to create an area that was to become the citys civic centre in the early ninth century.

The difficulties of dating olive wood

Olive wood is difficult to date for a variety of reasons, the most important of which is that one cannot tell visually what is an annual growth increment (usually referred to as a ‘ring’) and what is a sub-annual growth flush of which there may be any number in one growing season. (I have been able to count a dozen or more flushes in olive wood where the end of the growing season was somewhat more clearly marked than usual.) If one cannot determine the ring boundaries with certainty, one cannot do tree-ring dating, period. For Egyptologists reading this note, acacia is just as bad, and for the same reason. For 25 years I had a couple of sections of olive wood in my dendrochronology lab. Every term I would challenge students to tell me how many rings there were on them. No two students ever came up with the same answer and neither could I. An inspection of two different radii on the same piece also yielded widely varying results. (A side issue, not relevant here, is that the size of the ring in an olive tree does not necessarily reflect climatic conditions but rather the energies of the farmer or gardener who brings water to it. Thus olive is useless for purely dendrochronological cross-dating purposes.

Ion Uptake Determination of Dendrochronologically-Dated Trees Using Neutron Activation Analysis

Uptake of metal ions by plan roots is a function of the type and concentration of metal in the soil, the nutrient biochemistry of the plant, and the immediate environment of the root. Uptake of gold (Au) is known to be sensitive to soil pH for many species. Soil acidification due to acid precipitation following volcanic eruptions can dramatically increase Au uptake by trees. Identification of high Au content in tree rings in dendrochronologically-dated, overlapping sequences of trees allows the identification of temporally-conscribed, volcanically-influenced periods of environmental change. Ion uptake, specifically determination of trace amounts of gold, was performed for dendrochronologically-dated tree samples utilizing Neutron Activation Analysis (NAA) technique. The concentration of gold was correlated with known enviironmental changes, e.g. volcanic activities, during historic periods.