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A method for analysis of radiocarbon using direct absorption into an alkaline organic amine, and subsequent LSC, was introduced by Qureshi et al.(1989). This paper describes several modifications to that original idea by development of a recirculating closed-system and use of bladder system to store and deliver CO2. The modifications have increased the precision and useability of the method which ensures saturation of the Carbosorb and allows up to 5 samples to be prepared for counting per day per extraction line. Organic samples can also be prepared for LSC by using a Parr bomb which is much more efficient than conventional combustion in a stream of oxygen. Overall, the method has slightly lower precision than the benzene method but, in many instances, counting statistics are much less than the overall uncertainty contributed by inter- and intra-sample variability. Therefore, for applications in many instances where radiocarbon is used as a dating tool or as a tracer, the Carbosorb method now provides a rapid and less expensive alternative.

This paper considers the reliability of radiocarbon dates of moa eggshell from archaeological sites in New Zealand. In the light of certain problems associated with alternative materials, it is suggested that eggshell is a reliable material which survives well in archaeological contexts, possesses a minimal inbuilt age and usually dates the event in question most accurately. Nine preliminary results are presented from 4 sites; Onenui (Hawke's Bay), Shag Mouth, Pleasant River (both North Otago) and Warrington (Dunedin). Radiocarbon dates of eggshell are compared with those of other materials in identical contexts and the differences are found to be statistically insignificant.

The Last Termination is traditionally subdivided into the Oldest Dryas, Bølling, Older Dryas, Allerød, Younger Dryas and Preboreal Chronozones. This paper briefly summarizes the history of the Late Weichselian chronostratigraphic system and gives an overview of recent developments in radiocarbon dating terrestrial records between 15,000 and 10,000 14C years BP. Problems inherent in the traditional chronostratigraphy are discussed in the light of new and more advanced dating possibilities, including accelerator mass spectrometry (AMS) measurements on terrestrial macrofossils. New results obtained using AMS-14C dated varve sequences are compared with each other and with the marine U/Th coral record. In addition, the importance of time-synchronous marker horizons as a tool for long-distance correlation between different archives is illustrated.

The Pleistocene sequence of the Kleszczów Graben, central Poland, comprises seven fluvial series, ranging in age from Pre-Tiglian to Holocene. These sequences are investigated in terms of graben tectonics that existed up to the Middle Pleistocene and climate change ranging from periglacial to cool temperate. Warm temperate (interglacial) fluvial deposits are virtually absent. There is no evidence for tectonic control of fluvial sedimentation, although this is the factor that has controlled sediment preservation, deformation and erosion. In contrast, sedimentation has been influenced greatly by climatic conditions and climatic change, mainly as a response to changes in vegetation cover. Similar responses in the form of typical sedimentary successions are observed in fluvial series of different ages. This paper outlines the sequences of erosion and sedimentation and discusses their relation to the regional history of climatic changes, the geomorphic positions of river valleys and the positions of advancing ice-sheets.