The accelerator mass spectrometry (AMS) facility at Seoul National University (SNU-AMS) was accepted in December 1998 and results reported first at the Vienna AMS conference in October 1999 and at the 17th Radiocarbon Conference in Israel, June 2000. At the Vienna conference, we reported our accelerator system and sample preparation systems (Kim et al. 2000). Recent developments of the AMS facility have been regularly reported at AMS conferences (Kim et al. 2001, 2004, 2007). Meanwhile, about 1000 unknown archaeological, geological, and environmental samples have been measured every year. In this report, the archaeological and geological data carried out in 2002 are presented in terms of years BP (before present, AD 1950), following the SNU-AMS date lists I and II published in Radiocarbon (Kim et al. 2006a,b).

The incidence of plate-boundary earthquakes across 3 prospective tectonic segments at the Alaska subduction zone (ASZ) in the late Holocene is reconstructed from geological evidence of abrupt land-level change and archaeological evidence of discontinuities in occupation of native villages. Bracketing radiocarbon ages on uplifted and down-dropped coastal deposits indicate that great earthquakes likely ruptured the plate interface in the eastern segment (Prince William Sound [PWS]) about 800, 1400, 2200-2300, 2600-2700, 3100-3200, and 3600-3700 cal BP. Evidence for an event about 1900 yr ago, and the possibility that the 26002700 cal BP event was a closely spaced series of 3 earthquakes, is restricted to parts of Cook Inlet. Geological evidence from the central (Kenai [KEN]) segment is fragmentary, but indicates that this segment likely ruptured about 1400 yr ago and in the triple event about 2600-2700 yr ago. The geological record from the Kodiak-Katmai (KOKA) segment at the western end of the ASZ has limited time-depth, with localized evidence for ruptures about 500, 1000, and 1300 yr ago. 14C ages and stratigraphic descriptions from 82 prehistoric villages and camps on the coast of the Gulf of Alaska reveal fluctuations in site activity that correlate with paleoseismic episodes. Hiatuses in site occupation occurred about 800, 1400, and 2200 yr ago in the PWS and KEN segments. The fragmentary older record from the KEN segment also reveals a hiatus about 2700 yr ago. The 2200-2300 and 2600-2700 cal BP events are also recorded in the KOKA segment, and the great earthquake at about 3200 cal BP may also be recorded there. This suggests that, although the PWS and KEN segments behave as a coherent unit of the Alaska megathrust, the KOKA segment is characterized by semi-independent behavior. At least 2, and perhaps as many as 4, of the last 7 prehistoric great earthquakes at this plate boundary did not propagate this far west.

In this paper, we discuss how the radiocarbon dating of soot on oil lamps can help determine the chronology of the Jewish catacombs of Rome. We also explore the ramifications of our work for the typological study of Roman period terracotta lamps.

In the Great Basin of North America, big sagebrush (Artemisia tridentata Nutt.) growth rings can be used to reconstruct environmental changes with annual resolution in areas where there is otherwise little such information available. We tested the annual nature of big sagebrush wood layers using accelerator mass spectrometry (AMS) radiocarbon dating. Four cross-sections from 3 sagebrush plants were collected near Ely, Nevada, USA, and analyzed using dendrochronological methods. Ten 14C measurements were then used to trace the location of the 196-364 bomb spike. Although the number of rings on each section did not exceed 60, crossdating was possible within a section and between sections. Years assigned to individual wood layers by means of crossdating aligned with their expected 14C values, matching the location of the 14C peak. This result confirmed the annual nature of growth rings formed by big sagebrush, and will facilitate the development of spatially explicit, well-replicated proxy records of environmental change, such as wildfire regimes, in Great Basin valleys.

East Polynesia was the geographic terminus of prehistoric human expansion across the globe and the southern Cook Islands, the first archipelago west of Samoa, a gateway to this region. Fourteen new radiocarbon dates from one of the oldest human settlements in this archipelago, the Ureia site (AIT-10) on Aitutaki Island, now indicate occupation from cal AD 1225-1430 (1 sigma), nearly 300 yr later than previously suggested. Although now among the most securely dated central East Polynesian sites, the new age estimate for Ureia places it outside the settlement period of either the long or short chronology models. The new dates have, however, led to a comfortable fit with the Ureia biological evidence, which suggests not a virgin landscape, but a highly a modified fauna and flora. The results also provide the first systematic demonstration of inbuilt age in tropical Pacific trees, a finding that may explain widely divergent 14C results from several early East Polynesian sites and has implications for the dating of both island colonization and subsequent intra-island dispersals.

This article expands the date list from the Stone Age cave site of El Mirón in the Cantabrian Cordillera of northern Spain to a total of 62 radiocarbon determinations, one of the longest series from a single prehistoric site in Iberia. All the assays (accelerator mass spectrometry [AMS] and conventional, run on charcoal and bone collagen) were done by a single laboratory (Geochron, GX). The 11 new dates confirm 1) the late spread of Neolithic economy and technology into the Atlantic environment of Cantabrian Spain by about 4500 cal BC; 2) the horizontally extensive, but not intensive, use of the whole cave vestibule by Upper Magdalenian foragers about 12,000-14,000 cal BC; 3) extensive and very intensive, repeated occupations of the cave during the Middle and Lower Cantabrian Magdalenian about 14,200-17,000 cal BC; and 4) a long, gradual technological transition from the Solutrean to the Archaic Magdalenian between about 20,000-17,000 cal BC. El Mirón joins a list of culturally very rich, frequently occupied, Lower Magdalenian residential hub sitesmost of the rest of which (including Altamira) are located in the coastal lowlands of Cantabria which have yielded distinctive red deer scapulae that are decorated with striated engraved images of game animals (mainly red deer hinds), now most precisely dated at El Mirón between 16,200-17,200 cal BC.

This paper reports a further chronological assessment of the Christian catacombs of Rome by radiocarbon-dated organic materials in the so-called Liberian region of the catacombs of St. Callixtus on the Appian Way. 14C dates of various types of organic material are discussed and related to ages derived from numismatic evidence and epigraphic remains. The results show that this area of the catacombs of St. Callixtus is older than assumed by previous scholarship. We therefore conclude that the appellation Liberian region is a misnomer.

Previous work has suggested that seasonal and interannual upwelling of deep, cold, radiocarbon-depleted waters from the South Atlantic has caused variations in the reservoir effect (R) through time along the southern coast of Brazil. This work aims to examine the possible upwelling influence on the paleoreservoir age of Brazilian surficial coastal waters based on paired terrestrial/marine samples obtained from archaeological remains. On the Brazilian coast, there are hundreds of shell middens built up by an ancient culture that lived between 6500 to 1500 yr ago, but there are few shell middens located on open-coast sites with a known upwelling influence. Three archaeological sites located in a large headland in Arraial do Cabo and Ilha de Cabo Frio on the southeastern coast of Brazil, with open-ocean conditions and a well-known strong and large upwelling of the Malvinas/Falkland current, were chosen for this study. The 14C age differences between carbonized seed and marine samples varied from 281 +/- 44 to 1083 +/- 51 14C yr. There are also significant age differences between carbonized seed samples (977 14C yr) and marine samples (200 and 228 14C yr) from the same archaeological layer that cannot be explained by a reservoir effect or an old-wood effect for charcoal. Therefore, the present data from the southeastern Brazilian coast are inconclusive for identifying an upwelling effect on R. To do so, it would be necessary to more precisely define the present pre-bomb R in upwelling regions, and to analyze paired marine/terrestrial samples that are contemporaneous beyond doubt.