MEM22478 - Prehistoric burnt mound on Spooners (Monument)

As part of the Exmoor Mires Project, South West Archaeology were contracted to undertake a non-intrustive walkover survey of the proposed mire restoration area on Spooners. Located was a mound of approximately 8 metres diameter and up to 0.5 metres high on the upslope side. This is near a confluence of two streams in an unlikely position for a burial mound. [1] The Historic Environment Officer for the Exmoor Mires Project undertook a non-intrustive walkover survey of the proposed mire restoration area on Spooners, which included this site. The mound was seen to be stony, with a roughly circular shape and a diameter of c. 8 metres. It is situated at the confluence of Great Woolcombe with a southwest to northeast trending tributary stream. It is located at the northeastern end of an elongated ridge (MEM22493) measuring 16 metres long by 8 metres wide, present on the banks of the tributary. A further irregular mound is present to the northeast (MEM22492). The round earthwork may be a burial cairn of probable Bronze Age date, although its topographic location is highly unusual. An alternative interpretation, given the proximity of the stream is as burnt mound which range in date from the Neolithic to early Medieval period elsewhere. In this case the positive ridges may form part of the feature. This was located atop an elongated mound measuring c. 16 metres long by 8 metres wide with a stony make-up was noted. It may be a natural feature, but may also be anthropogenic and form part of a larger feature with the mound. [2] A gradiometer survey was undertaken at Spooners in April 2013 after field walkover survey had identified some possible archaeological remains. The earthwork morphology and landscape location indicated the possibility that these remains were a burnt mound and as such would represent the second burnt mound so far discovered on Exmoor. The earthwork morphology combined with the gradiometer data clearly indicates a burnt mound structure. Burnt mounds have features that enable their relatively easy classification as field monuments: they are nearly always horseshoe or ‘u’ shaped and they are found close to water. On excavation, they are found to be composed mainly of burnt stones and within the arc of the ‘u’ shape there tends to be a pit or ‘trough’ lined with timber or clay. Nearby is often found a hearth. Such structures are generally Bronze Age in date and occur within liminal areas, possible at territory edges. The form of the interpreted data indicates a raised area of burnt deposits, possibly with two mounds and a trough, where water heating was occurring using burnt stones. The highly magnetic contrast of the monument can be accounted for by the process of placing hot stones in a water-filled trough which then rapidly cool and then these stones are redeposited creating a remnant magnetism. The presence of possible distinct features within the burnt mount adds a further dimension to the data and could act as a focus for future work. The incision of the extant springlines add a further dimension to the data, potentially indicating that the burnt mound may be located on a significant Holocene sediment sequence. Whilst this requires further investigation, the provisional dating of the monument as Bronze Age burnt mound, indicates the possibility of a significant early Holocene deposits. [3] A metric survey on Spooner’s Allotment was carried out in 2014 to record and accurately these earthworks. Two mounds joined by a bank were visible at the confluence of two streams. The mound at the northeast end is the best defined and is mostly turf covered and very stony. It is 6.5 metres northwest-southeast, 7 metres northeast-southwest and a maximum of 1 metre high and has a pronounced ridge of stone on its west side. The mound at the southwest end (previously recorded separately as MEM22478) is also stony and fragments of burnt quartz were seen on the north edge. It measures 5 metres northeast-southwest, 6 metres northwest-southeast and is a maximum of 1.4 metres high. The bank which links the two mounds is 5 metres long and 0.5 metres high, with a curve on its south side, forming a small level area between the mound and the edge of the stream. The feature has overall measurements of 17 metres northeast-southwest by 6.5 metres northwest-southeast. The location close to a stream, the morphology of the feature and the evidence of burning from both geophysics and ground evidence all suggest a burnt mound of prehistoric date. [4] An archaeological evaluation was undertaken by Oakford Archaeology during October 2014. The work comprised the excavation of a single trench across the remains of a suspected Bronze Age burnt mound previously identified through walkover and geophysical survey. Excavation revealed a dense, black spread of heat affected stone and charcoal, which appears to represent in situ burnt mound material. This has been radiocarbon dated to the early to mid Bronze Age. [5]