Microfossil provenance of British Iron Age lowland ceramic artefacts

陶器是后来史前生活的许多方面的中心，陶器和制作陶器的粘土在许多社会中具有强大的实用和隐喻作用。在过去的30年里，根据陶瓷织物的特征宏观包裹体来定义陶瓷织物，并提出所用原材料的来源，已经成为标准的考古实践。然而，特征和来源的研究主要局限于具有独特岩石类型的粘土和包裹体，如来自蜥蜴半岛的蛇纹岩。相比之下，英国南部和东部的大部分地区由沉积矿床组成，没有矿物学上的离散露头。因此，对史前英国大部分地区陶瓷生产和交换组织的调查受到阻碍。虽然来自沉积岩序列的陶瓷的矿物学含量可能不清楚，但这种岩石的微化石特征可以提供一个强有力的来源指示。在这里，我们使用微化石来调查在东米德兰兹郡为数不多的山堡之一的伯罗山铁器时代聚居地用于粘土和陶瓷的原材料的来源。该遗址以前的发掘表明，从新石器时代到公元4世纪，占领最密集的时期是铁器时代，当时这座山是该地区人口的主要前城市中心。伯罗山坐落在铁器时代人口稠密的土地上，周围是农场和居民点。一项正在进行的五年工作计划的考古证据已经证明，居住在这里的社区有广泛的联系，但到目前为止，这项工作仅限于相对罕见、价值较高的或稀有物品，如克伦石。2010年和2011年的发掘发现了一系列陶瓷，从公元前4世纪到公元1世纪，位于正门和山堡北缘内的房屋和被占领的沉积物中。然而，在伯罗山和整个东米德兰兹郡，铁器时代社区的陶瓷剧目基本上是由一种风格保守、地理分布广泛、历史悠久的陶瓷传统主导的，这种传统被称为“刻痕陶器”。虽然其面料的宏观多样性早已被认识到，但很难确定这种材料的特征和来源。圆屋的泥浆和用于建造城墙的粘土包括在山堡购买铁器时代粘土的其他例子。考古调查已经发现了山堡内的数百个储藏坑和城墙背风面的一系列圆形房屋，以及紧邻山堡以东的城墙外的一个定居点。2011年和2012年的挖掘将对每个地区进行采样，以从定居地获得横截面材料。Burough Hill位于中生代沉积碳酸盐和碎屑岩的景观中，上面覆盖着晚第四纪的冰川。东米德兰兹山脉中生代岩石的微古生物学有很好的记载。不太为人所知的是这些墓穴的微化石特征，其中包含从约克郡和林肯郡的白垩纪微化石中回收的白垩纪微化石，以及更多来自当地的侏罗纪微化石。伯罗希尔的初步研究已经在陶瓷和用于建造墙壁的粘土材料中发现了丰富的介形类和有孔虫。结合对山堡附近固体和漂流沉积物的微化石和沉积学特征的详细评估，该遗址提供了一个很好的案例研究，可以用来评估沉积景观中陶瓷和粘土材料的地质来源，因此我们的研究具有询问英国景观中其他考古遗址的广泛潜力。

Ceramics were central to many aspects of later prehistoric life and the pottery and the clays from which they were made had a powerful practical and metaphorical role in many societies. Over the last 30 years it has become standard archaeological practice to define ceramic fabrics in terms of their characteristic macroscopic inclusions and to suggest sources of the raw materials used. Characterisation and sourcing studies have, however, largely been restricted to clays and inclusions with distinctive rock types such as serpentinite from the Lizard peninsula. Much of southern and eastern Britain by contrast, consists of sedimentary deposits with an absence of mineralogically discrete outcrops. Consequently, investigation of the organisation of ceramic production and exchange in much of prehistoric Britain is hampered. Whereas the mineralogical content of ceramics sourced from sedimentary rock successions may be indistinct, the microfossil signature of such rocks can provide a powerful indication of provenance. Here we use microfossils to investigate the source of raw materials used in clays and ceramics at the Iron Age settlement of Burrough Hill, one of the few hill-forts in the East Midlands. Previous excavations at the site demonstrate occupation from the Neolithic to the 4th century AD, with the most intensive period of occupation during the Iron Age when the hill was a major pre-urban centre for the population of the region. Burrough Hill sat in a densely occupied Iron Age landscape of farms and settlements. Archaeological evidence from an ongoing five-year programme of work already attests to the wide ranging contacts of the community living here, but this work has so far been limited to comparatively rare, high value or exotic items such as quern stones. Excavations during 2010 and 2011 have identified a range of ceramics from 4th century BC to 1st century AD at the main entrance and from houses and occupation deposits inside the northern edge of the hill-fort. At Burrough Hill and across the East Midlands generally, however, the ceramic repertoire of Iron Age communities is dominated by a stylistically conservative, geographically widespread and chronologically long-lived tradition of ceramics known as 'Scored wares'. Whilst the macroscopic diversity of its fabrics has long been recognised, it has rarely been possible to characterise and provenance this material.Mud daub from the round houses and clay used in the construction of the ramparts comprise other examples of Iron Age clay procurement in the hill-fort. Archaeological investigation has already identified several hundred storage pits within the hill-fort and a series of round houses to the lee of the ramparts as well as an extramural settlement immediately outside the ramparts to the east of the hill-fort. Excavations in 2011 and 2012 will sample each of these areas to get a cross section of material from the settlement.Burrough Hill is situated in a landscape of Mesozoic sedimentary carbonate and clastic rocks over which are smeared tills of late Quaternary age. The micropalaeontology of the Mesozoic rocks of the East Midlands is well documented. Less well known is the microfossil signature of the tills, which contain Cretaceous microfossils recycled from the Chalk Group of Yorkshire and Lincolnshire mixed with more locally derived Jurassic microfossils. Pilot studies at Burrough Hill already identify a rich repository of ostracods and foraminifera in ceramics, and in clay materials used to the construct walls. In conjunction with a detailed evaluation of the microfossil and sedimentological signature of the solid and drift deposits of the immediate vicinity of the hill-fort, the site provides an excellent case study by which to assess the geological provenance of ceramic and clay materials in a sedimentary landscape, and our study thus has widespread potential for interrogating other archaeological sites in the British landscape.