Considerations on the provenance determination of plant ash glasses using strontium isotopes
Considerations on the provenance determination of plant ash glasses using strontium isotopes
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DOI：
10.1016/j.jas.2010.07.014
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发表时间：
2010-12-01
影响因子：
2.8
通讯作者：
Vanhaecke, Frank
中科院分区：
文献类型：
--
作者：
Degryse, Patrick;Shortland, Andrew;Vanhaecke, Frank
锶同位素分析被认为是确定古植物灰玻璃原生产地的一种合适的方法。这项技术是基于这样的假设，即锶进入这种玻璃类型时，植物灰用作熔剂材料，生成的玻璃的(87)锶/(86)锶比值反映了该熔剂的地质来源。在这种情况下，生长在基岩上的植物应该继承基岩中的大部分锶同位素成分，保持不变。不同类型的植物灰玻璃具有非常不同的(87)锶/(86)锶组分。本文测定了生长在不同基岩类型上的几种植物的(87)锶/(86)锶组成，并与基岩的整体锶同位素组成和岩石学进行了比较。研究表明，这些植物的~(87)Sr/~(86)Sr比值不仅是或主要是当地地质条件的函数，而且还与植物总耗水量的锶同位素组成有关。这很可能既依赖于植物物种，也依赖于紧邻工厂周围地区的小规模水文。这样，地质露头的同位素组成与生长在基岩上的植物之间就不能推断出明确的关系。因此，由这种植物制成的植物灰烬的同位素组成是不确定的，而且还取决于物种。虽然利用锶同位素可以在时间和空间上对一组植物灰玻璃进行比较，但可能很难确定特定地理地质区域的植物灰玻璃类型。(C)2010爱思唯尔有限公司。保留所有权利。
Strontium isotopic analysis has been proposed as a suitable method to determine the primary production location of ancient plant ash glasses. The technique is based upon the assumption that Sr enters this glass type with the plant ash used as a flux material, and that the (87)Sr/(86)Sr ratio of the resulting glass reflects the geological provenance of that flux. In such case, the bulk Sr isotopic composition of the bedrock should be inherited unchanged in the plants growing on that bedrock. Different types of plant ash glasses have been shown to have widely differing (87)Sr/(86)Sr compositions. In this study, the (87)Sr/(86)Sr composition of several plant species growing on different bedrock types is measured, and compared to the bulk Sr isotopic composition and petrology of that bedrock. The paper shows that the (87)Sr/(86)Sr ratio of these plants is a function not only, or even mostly, of the local geology, but also of the Sr isotopic composition of the total water consumed by that plant. This is highly likely to be both plant species dependent and dependent on the small-scale hydrology of the area immediately surrounding the plant. In this way, no definite relation between the isotopic composition of a geological outcrop and the plants growing on this bedrock can be inferred. Hence, the isotopic composition of a plant ash made from such plants is uncertain and moreover species dependent. Though groups of plant ash glasses can certainly be compared in time and space using Sr isotopes, it may prove difficult to ascertain a plant ash glass type to a specific geographical-geological region. (C) 2010 Elsevier Ltd. All rights reserved.