Source/Archive record SEM8100 - An archaeological gradiometer and earth-resistance survey: Land at Ashcombe, Simonsbath, Exmoor, Somerset

The magnetic and resistance contrasts across the survey areas were sufficient to be able to differentiate between anomalies representing possible archaeological features and background responses. Both pre-1889 and post 1889 changes to the deposits within the survey area were highlighted within the magnetic (gradiometer) and earth-resistance data sets; 1889 being the year of the publication of the Ordnance Survey first edition map that includes the survey area. A possible former field or enclosure boundary was recorded as partially coinciding with a modern footpath and also partially coinciding with a path created for the Simonsbath House garden and plantation which was mapped by the Ordnance Survey between 1889 and 1962 and recorded in a recent archaeological earthworks survey. Further evidence of this path, not recorded in the recent earthworks survey, was recorded in the earth-resistance data. A possibly branching path, track that pre-dates the publication of the Ordnance Survey first edition map but not necessarily the date of the creation of the Simonsbath House garden and plantation, was recorded in both the gradiometer and earth-resistance data. A possible structure was recorded in the earth-resistance data on the western bank of Ashcombe stream that was not recorded in the 1889 first edition Ordnance Survey map or later maps. A further deposit of rubble or a structure was recorded in the resistance data close to the Ashcombe stream on the southern boundary of the survey area. Again this potential archaeological deposit was not recorded on any Ordnance Survey map. An examination of natural deposits recorded in the data set suggested that the removal of a garden path and the creation of an alternative path between 1891 and 1903 was probably due to water saturation of the ground resulting from works associated with the creation of the Simonsbath House garden and plantation. Field drainage, evident in the gradiometer data set, appears to have been undertaken to mitigate the wet ground associated with natural drainage channels recorded in the earth-resistance survey. There is evidence in the resistance data for either a re-routing of the Ashcombe stream or a palaeochannel of the same close to the modern bridge across the stream. This channel and the potential structure recorded in the earth-resistance data on the western bank of Ashcombe stream are together likely to be the origin of the low earthworks that prompted this survey.