Contribution of strontium to the human diet from querns and millstones: an experiment in digestive strontium isotope uptake

The question of whether rock grit ingested unintentionally from querns, metates or millstones, or deliberately through pica or geophagy, is bioaccessible in the human gut has not been addressed in archaeological strontium (Sr) isotope studies. This study employed the unified bioaccessibility method and determined that ingested rock grit can provide bioaccessible ⁸⁷Sr/⁸⁶Sr, but that unintentional consumption is unlikely to constitute > 1% of the diet (by mass) and will not significantly change, that is, by > 0.001, human skeletal ⁸⁷Sr/⁸⁶Sr. The use of locally or non‐locally sourced querns or millstones will not affect the interpretation of archaeological human ⁸⁷Sr/⁸⁶Sr values in Britain.     

Late Ordovician cephalopods,tentaculitides, machaeridians and echinoderms from Kuh-e Faraghan,High Zagros,Iran

Ghavidel-Syooki, M., Evans, D.H., Ghobadi Pour, M., Popov, L.E., Álvaro, J.J., Rakhmonov, U., Klishevich, I.A. & Ehsani, M.D., 15.5.2015. Late Ordovician cephalopods, tentaculitides, machaeridians and echinoderm columnals from Kuh-e Faraghun, High Zagros, Iran. Alcheringa 39, 530–549. ISSN 0311-5518.

Late Ordovician (Katian, uppermost Acanthochitina barbata to Armoricochitina nigerica chitinozoan zones) cephalopods, tentaculitides, machaeridians and echinoderms are documented for the first time from the southern Zagros Ranges. A low-diversity cephalopod fauna includes Geisonocerina dargazense sp. nov., Isorthoceras sp. cf. I. bisignatum (Barrande) and other undetermined orthoceratides. The presence of Late Ordovician tentaculitides in the high- to mid-latitude margins of Gondwana has been documented previously, but no examples have been described in detail. Thus, Costatulites kimi sp. nov., which currently occurs associated with brachiopods characteristic of the Svobodaina havliceki (brachiopod) Association, represents the earliest undoubted record of tentaculitides in Gondwana. Machaeridians constitute a relatively common component of the Late Ordovician benthic faunas from the Mediterranean margin of Gondwana, but no previous records on the Gondwanan Iranian-Arabian segment have been reported. Three echinoderm taxa based on dissociated columnals are documented from the Armoricochitina nigerica chitinozoan Zone, including Sumsaricystis radiatus Stukalina, Ristnacrinus sp. and Rosulicrinus rosulus Stukalina.

Mohammad Ghavidel-Syooki [m_ghavidelsyooki@yahoo.com] Institute of Petroleum Engineering, Technical Faculty of Tehran University, PO Box 11365-4563, Tehran, Iran; David H. Evans [david.evans@naturalengland.org.uk], Natural England, Suite D, Unex House, Bourges Boulevard, Peterborough PE1 1NG, UK; Mansoureh Ghobadi Pour* [mghobadipour@yahoo.co.uk], Department of Geology, Faculty of Sciences, Golestan University, Gorgan, Iran; Leonid E. Popov [leonid.popov@museumwales.ac.uk], Department of Geology, National Museum of Wales, Cathays Park, Cardiff CF10 3NP, UK; J. Javier Álvaro [jj.alvaro@csic.es], Instituto de Geociencias (CSIC-UCM), c/ José Antonio Novais 2, 28040 Madrid, Spain; Utkyr Rakhmonov, Kitab State Geological Reserve, 9 Ipak Yuli Street, Sakhrisabz, Uzbekistan; Inna A. Klishevich, Department of Historical Geology, Geological Faculty, St Petersburg State University, Universitetskaya Naberezhnaya 7/9, 199034 St Petersburg, Russia [inna@IK4848.spb.edu]; Mohammad H. Ehsani [mh_ehsani@hotmail.com], Institute of Petroleum Engineering, Technical Faculty of Tehran University, PO Box 11365-4563, Tehran, Iran. *Also affiliated with Department of Geology, National Museum of Wales, Cathays Park, Cardiff CF10 3NP, UK.     

Rugged Plateaus and Extensive Floodplains — Modelling Landform Evolution in a Northern Australian Catchment

Medium to large natural catchments are often more spatially heterogeneous than small catchments or single landforms. Attempting to model landform evolution of large areas is consequently more complex. This paper demonstrates that modelling landform evolution in medium to large catchments can be improved by calibrating the model to smaller, more geomorphologically homogenous sub‐catchments. The paper investigates landform evolution in the Ngarradj catchment in the Northern Territory of Australia (a medium scale catchment of approximately 67 km²). The catchment is complex and contains two distinct landform regions; an upland plateau region with highly dissected sandstone and shallow, sandy soils, and a lowlands region with gentle, wooded slopes and floodplains with deep, sandy soils. The SIBERIA landform evolution model is calibrated and applied to the Ngarradj catchment. The complexity of the Ngarradj catchment is incorporated into the modelling by dividing the catchment into three sub‐catchments (Swift Creek (SC), Upper Main (UM) and East Tributary (ET)) which are relatively homogeneous and for which hydrology and sediment transport data are available. A discharge‐area relationship and long‐term, sediment loss rates for the catchment are derived based on an annual series flood frequency analysis of a 20 year runoff record predicted in a previous study. Sediment transport modelling incorporates both suspended and bedload sediment loss. The denudation rates derived using these data are 37, 63 and 77 mm kyr^?1 for the SC, UM and ET sub‐catchments, respectively. Model predictions indicate that the UM sub‐catchment will have the greatest mean erosion. This is balanced by the large amount of deposition that will occur in the upper Ngarradj valley of the UM sub‐catchment. Further deposition occurs on the floodplain of Ngarradj, with the area between the SC and ET/UM (up‐stream) sub‐catchments experiencing a small net accretion of sediment (15 mm kyr^?1).     

The elemental chemistry of lithic microwear: an experiment

This paper examines the ability of elemental analysis to distinguish microwear traces on stone tools. Our research hypothesised that cleaning procedures of experimental specimens may have heavily influenced previous studies in this area. Experimental flakes are used and cleaned by two alternative methods before laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is applied to study use-wear chemistry. The results show that elementally recognisable traces remain on stone surfaces even with severe cleaning. Also studied were archaeological sickle blades from two sites in Northern England. The results were counter-intuitive demonstrating that experimentally validated models potentially require extensive modification and clarification before being applied to archaeological material. This research identifies methodological problems and errors concerning cleaning within previous experimental studies and highlights new directions for this quantitative analytic approach in microwear analysis.