Figure 2. Site Sections.
York Archaeological Trust
Seven boreholes, forming two transects across the site, were sunk during the course of the excavations (Fig. 1). The cores were continuously and carefully monitored by an archaeologist.' The north-west/south-east transect continued a line of boreholes taken by York Archaeological Trust on the Garden Place car park site immediately to the south-east in 1989.
|
|
|
|
Figure 2. Site Sections. |
The top of undisturbed natural deposits occurred at between 3.6m and 5.Om Above Ordnance Datum. The maximum height was obtained from Borehole 2, in the middle of the site. On the northwest/southeast borehole alignment, the natural deposits reach a maximum height of 4.7m AOD at Borehole 7. From that point, they slope down steadily to the north-west (reaching 3.6m AOD in Borehole 6) and to the south-east (to as low as 3.Om AOD in 1989 Borehole 4). Archaeological examination in the early 1950s on the site of the Telephone Exchange to the west of the present site indicated that, during the Roman period, the River Foss occupied a channel well to the north of its present course; the base of the channel was at 3.Om AOD, and the top at 5.Om AOD. Consequently, it appears that the Carmelite Street site would have been dry land prior to the medieval period, with channels roughly 2.Om deep to the north-west and south-east. This dry land may have bean a peninsula, formed by the confluence of the River Foss and the Tang Hall Beck; or it may have been an island in the River Foss.
The composition of the natural deposits is variable.
Boulder clay occurs at an average height of 1.Om AOD. Above this, a thick gravel layer observed in the 1989 boreholes gives way to thinner deposits of clay, sand and gravel to the northwest. This may be due to changes in the course of the River Foss prior to the Roman period.
Above undisturbed natural was a series of clay silts approximately 2.Om thick overall, and attaining a high point at 5.9m AOD. Environmental analysis suggests that these silts are the result of deposition in slow-flowing water. This deposition was extensive, having been found at the Garden Place car-park, Carmelite Street and Telephone Exchange sites. Pottery recovered from Borehole 7 points to a medieval date for the bulk of these deposits, and it is therefore suggested that they were formed in the King's Fishpool, a lake which resulted from the damming of the River Foss to create a moat around York Castle. Environmental analysis of borehole samples indicates that, while some of these deposits were alluvial, others (notably sample 005) were formed by dumping waste matter into a body of water.
Thick clays and silt clays, lying above the organic silts in Boreholes 6 and 7 (to a maximum height of 6.8m AOD). Are believed to represent land reclamation on the north side of the King's Fishpool.
Layers of brick and mortar rubble, observed in Boreholes 4 and 6, may be part of much thicker and more extensive rubble layers noted in the 1989 boreholes, and suggest a further phase of reclamation of the King's Fishpool.
A homogeneous silt clay loam (or similar), about 0.5m thick and as high as 8.Om AOD, is considered to be a post-medieval garden soil. This is sealed by brick walls and rubble relating to modern activity on the site.
Sources:
Richardson, K.M., Excavations- in Hungate, York Archaeological Journal 116 (1959), pp. 51-114.
