6.2. Designated and Known Wrecks
- No designated sites have been identified within the datasets for the marine archaeology study area.
6.2.1. Desktop Data
- The wrecks and obstructions dataset held by the UKHO was consulted for relevant marine archaeology records. No UKHO records for wrecks or obstructions are located within the Array. Two wrecks are present on the NRHE (Canmore) database. Their distribution is shown in Figure 6.1 Open ▸ .
- One previously unrecorded wreck (Canmore ID 372595) is located within the Array. The record originated from discovery during the site-specific survey operations within the site boundary. This is included in the discussion of high potential anomalies in section 6.3.3.
- One wreck (Canmore ID 372955) is located within the marine archaeology study area. The wreck was observed during previous geophysical survey operations but is out with the limits of the site-specific geophysical survey data, approximately 380 m from the northern boundary of the Array. As this was an observation only, no geophysical data for this position exists and is therefore not corroborated by geophysical seabed features assessment detailed in section 6.3.
Figure 6.1: Marine Archaeology Identified Within the Marine Archaeology Study Area
6.3. Geophysical Seabed Features Assessment
- A total of 324 anomalies of potential archaeological interest were identified within the marine archaeology survey area during the archaeological assessment of the geophysical data. Of these, 295 are within the Array and the remaining 29 anomalies lie outside of the Array but within the extents of the geophysical survey area. Of the 324 anomalies, three have been classified as high potential anomalies (further discussed in section 6.3.3), 14 as medium potential, and 307 as low potential anomalies. The distribution of these can be seen in Figure 6.2 Open ▸ . Full details of the anomalies of archaeological interest identified during the geophysical survey are presented in volume 3, appendix 19.1, annex C.
6.3.1. Low Potential Anomalies
- The 307 low potential anomalies predominantly represent likely geological features, modern debris such as infrastructure, chain, cable or rope, or small items of debris with no features indicating archaeological potential and are therefore not considered further within this report. The locations of the low potential anomalies are presented in volume 3, appendix 19.1, annex C and are considered in the outline WSI and PAD (volume 3, appendix 19.2).
Figure 6.2: Geophysical Anomalies Within the Marine Archaeology Survey Area
6.3.2. Medium Potential Anomalies
- Medium potential anomalies are those that have characteristics that indicate a likelihood of representing anthropogenic material such as debris or potential debris.
- The 14 medium potential anomalies are presented in Table 6.3 Open ▸ and the distribution of these is shown in Figure 6.3 Open ▸ .
- Further assessment of the medium potential anomalies, possibly by Remotely Operated Vehicle (ROV) would be required to better understand the origin and character, and therefore the archaeological significance of all medium potential anomalies.
Table 6.3: Medium Potential Anomalies
Figure 6.3: Distribution of Medium and High Potential Anomalies Within the Marine Archaeology Survey Area
Figure 6.4: Medium Potential Anomalies Within the Marine Archaeology Survey Area
Figure 6.5: Medium Potential Anomalies Within the Marine Archaeology Survey Area
Figure 6.6: Medium Potential Anomalies Within the Marine Archaeology Survey Area
6.3.3. High Potential Anomalies
- The three high potential anomalies are described in this section and the distribution of these is shown in Figure 6.3 Open ▸ . Two have been located within the Array and one is located outside the Array boundary.
- Anomalies that are likely to represent archaeological features have been classed as high potential anomalies. The high potential anomalies include two wrecks and one potential wreck.
- Further assessment of the high potential anomalies, possibly by ROV, would be required to better understand the origin, and therefore the archaeological significance of all high potential anomalies.
- OS23_092 lies 910 m from the north-west boundary of the Array. The anomaly is visible in the SSS dataset but outside the MBES acquisition area and has no associated magnetic anomaly. The location does not correlate with any UKHO or NRHE records.
- The anomaly has been classified as high potential based on its form, which is an irregular mound that measures 15.6 m x 5.4 m x 0.8 m, and protrusions are visible to the mound’s north and south. The overall size of the anomaly may indicate the potential remains of a wrecked vessel.
- OS23_312 lies in the south-east portion of the Array. The anomaly is visible in the SSS and MBES data, has an associated magnetic anomaly of 202.4 nT, but does not correlate with any UKHO or NRHE records.
- The anomaly clearly represents the remains of a wrecked vessel, measuring 33.7 m x 6.6 m with a measurable height of 2.8 m. The wreck is oriented north-west to south-west, with the bow towards the north-west. The wreck appears largely coherent, though there is evidence of collapse circa 9.0 m amidships from the bow. Features visible in the SSS dataset suggest that the wreck may lie on the seabed upside down. Other than being of at least partial ferrous construction, no other characteristics of the wreck are known, such as its age or date of sinking. Linear features, likely ropes, chains, or wire extend from the stern, potentially originating from the wreck itself or as a result of snag from another vessel. Despite not correlating with any UKHO or NRHE records, based on the measurements of the anomaly, it is possible that OS23_312 may represent the remains of one of two recorded losses: either Scottish Queen (Canmore ID: 313238) or Titan (Canmore ID: 328826).
- OS23_314 lies 4.3 km from the western boundary of the Array. The anomaly is visible in the SSS and MBES data, has an associated magnetic anomaly of 41.0 nT. The location does not correlate with any UKHO records but has an associated NRHE record (Canmore ID 372595) which was created by the survey contractor when the anomaly was originally observed during data acquisition.
- The anomaly is the remains of a wrecked vessel measuring 59.3 m x 13.0 m and with a measurable height of 5.1 m. The wreck is oriented north-west to south-east; it is not possible to identify the bow though it potentially lies to the south-east. The wreck is largely collapsed and broken up. Other than the association with a magnetic anomaly which suggests at least partial ferrous construction, it is not possible to provide an age, or a date of sinking. The measurements of the wreck leave open the possibility that this anomaly represents the remains of one of two recorded losses: either Svein Jarl (Canmore ID 314131) or Duva (Canmore ID 313790).
- The anomaly was subject to additional specialist shipwreck analysis which identifies the wreck as a MV (merchant vessel) coaster or submarine (McCartney, 2023). From the additional assessment, the most likely scenario is that the seabed anomaly represents a ‘coaster’ vessel that has inverted while sinking, and subsequently collapsed. Although an alternative scenario is also presented in which the anomaly represents a previously unknown wreck of a submarine (McCartney, 2023). This would indicate a wartime loss, but cannot be firmly concluded without further investigation.
Figure 6.7: High Potential Anomalies Within the Marine Archaeology Survey Area