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Holocene Chronology of the Brattforsheden Delta and Inland Dune Field, SW Sweden

Alexanderson H., Fabel D.

Geochronometria

2015

Vol. 42, no.1

1--16

Brattforsheden is a large glacifluvial deposit in southwestern Sweden and associated with it is one of Sweden’s largest inland dune fields. Although the relative ages of the Brattforsheden deposits are well known, absolute ages from the area are few. In this study we have used optically stimulated luminescence (OSL), surface exposure (10Be) and radiocarbon (14C) dating to provide an absolute chronology for the deglaciation and for the Holocene development of the aeolian dunes. Our data show that the deglaciation took place just before 11 ka (11.5 ± 0.6 ka OSL, 11.3 ± 0.8 ka 10Be), in line with the 14C-based regional deglaciation age. Aeolian dunes started forming immediately after deglaciation and were active for at least 2000 years, well after vegetation had established. Renewed aeolian activity occurred 270–180 years ago, resulting in the deposition of sand sheets. Comparison between dating methods and studies of OSL dose distributions show that glacial, glacifluvial and littoral sediments suffer from incomplete bleaching and thus that mean OSL ages from such deposits overestimate the true depositional age. By using small aliquots and statistical age models, this effect can partly be countered. Also, some of the 10Be ages appear too old, which may be due to previous exposure.

Vertebrate tracks in Late Pleistocene–Early Holocene (?) carbonate aeolianites, Paphos, Cyprus

Milàn J., Theodorou G., Loope D. B., Panayides J., Clemmensen L. B., Gkioni B.

Annales Societatis Geologorum Poloniae

2015

Vol. 85, No. 3

507--514

In 2005, numerous vertebrate tracks were discovered in carbonate aeolianites in and around the town of Paphos, in the south western part of Cyprus. The main track-bearing exposure is located in a protected archaeological site near the Agia Solomoni Church in side the city of Paphos, where cross-sec tions through tracks are abundant in vertical exposures of the aeolianite along Apostolou Pavlou Avenue. Some exposures show as many as 10 tracks per m2 of vertical exposure. Several additional tracks were found in the extensive subterranean tomb complex, the Tombs of the Kings, just outside Paphos. The aeolian deposit was formed when westerly to southwesterly windsdrove fine- to medium-grained calcareous sand onshore from the beach. This generated low coastal dunes, represented by 1–2-m-thick, cross-bedded sets made up of grainflow and wind-ripple strata, and sand sheets composed entirely of wind-ripple strata. The sediment does not yet have an absolute date, but is considered to be of Late Pleistocene to Early Holocene age, as are many other coastal aeolianites in the Mediterranean area. The Late Pleistocene endemic fauna in Cyprus was limited to the dwarf hippopotamus Phanourios minor Desmarest, 1822, the dwarf elephant Elephas cypriotes Bate, 1902, a small carnivore Genetta plesictoides Bate, 1903, and (possibly) humans. The exposed tracks are 5–15 cm in diameter, with a few tracks up to 23 cm in size. This range of size correlates well with the estimated foot size of dwarf hippopotami and dwarf elephants. This low-diversity, endemic is land fauna provides a unique opportunity to correlate tracks with trackmakers.