Appendix 11 Marine Archaeology – Baseline Environment

Appendix 11
Marine Archaeology – Baseline Environment

11.1.   Desktop Study

  1. This section outlines the initial desk-based review of literature and data sources for marine archaeology to support this Scoping Report ( Apx Table 11.1   Open ▸ ).

 

Apx Table 11.1:
Summary of Key Data Sources

Apx Table 11.1: Summary of Key Data Sources

 

11.2.   Site-specific Survey Data

  1. A geophysical survey was undertaken within the site boundary. Multibeam Echo Sounder (MBES) Bathymetry, Sidescan Sonar (SSS), Magnetometer, Sub-Bottom Profiler (SBP), two-dimensional Ultra-High Resolution Seismic (2D UHRS) data were collected by Ocean Infinity between March and July 2022 (Ocean Infinity, 2022a; Ocean Infinity, 2022b). The purpose of the survey was to collect baseline information to inform this Scoping Report and the Array Environmental Impact Assessment (EIA) Report regarding seafloor conditions, subsurface interpretation and obstructions. The data collected varied in specification however is considered comparable and appropriate to allow for the characterisation of the marine archaeological potential in the vicinity of the Array.
  2. Main lines were acquired every 200 m and crosslines every 1 km. The geophysical survey was divided into two phases: a sparse survey (phase 1A) based on a 1 km x 1 km grid, and a dense survey (phase 1B) which includes the remaining 200 m spaced lines excluded previously in phase 1A. This marine archaeology baseline section is based upon the results of the phase 1A survey.
  3. The data was collected to a specification appropriate to achieve the following interpretation requirements:
  • magnetometer: identification of contacts > 5 nT (phase 1A), and >10 nT (phase 1b);
  • SSS: ensonfication of contacts > 0.5 m;
  • SBP: penetration 5 m to 10 m; and
  • MBES: ensonification of contacts < 1.0m.
  1. All data were collected and referenced relative to the WGS84 datum and UTM30N projection. Details of the survey specification of the offshore geophysical survey are presented within Apx Table 11.2   Open ▸ .

 

Apx Table 11.2:
Offshore Geophysical Survey Specification

Apx Table 11.2: Offshore Geophysical Survey Specification

 

11.3.   Baseline Characterisation

11.3.1 Submerged prehistoric archaeology

  1. The area of the marine archaeology study area (section 7.4, Figure 7.7   Open ▸ ) was submerged during the late glacial/early Holocene. Prior to this, the area was covered in a succession of ice sheets. During periods of glaciation the area would have been uninhabitable, however, during inter-glacial periods when at times the seabed would have formed dry land, there is a potential for periglacial occupation. The edges of channels and floodplains are likely to have the highest potential for the survival of archaeological material, as this is where prehistoric ground surfaces and organic material are most likely to survive. These deposits often lie beneath relatively thin layers of seafloor sediment and therefore may be vulnerable to exposure (BEIS, 2022f).
  2. Brooks et al. (2011) have produced reconstructed palaeogeography maps to understand the potential changes in palaeocoastlines of the UK and north-western Europe. This modelling predicted that the majority of the marine archaeology study area has been submerged for at least 20,000 years Before Present (BP), however, there was a small island, or archipelago of islands, subaerially exposed in the south-west corner of the marine archaeology study area, which is likely to have been exposed until approximately 10,000 years ago BP, after which it was submerged (Brooks et al., 2011; EMODnet, 2022). It is unlikely that any archaeological material from this period will have survived due to the effects of repeated glaciations, marine transgressions and associated fluvial activity (BEIS, 2022f).
  3. In the wider context, the marine archaeology study area is located within Regional Sea 1 (BEIS, 2022f) which experienced relatively early transgression compared to more southerly areas (i.e. Regional Sea 2). In addition, the strong current conditions in Regional Sea 1, the exposure to North Atlantic storms and the thin sediment cover in many places also make some areas of the shelf likely poor prospects for the survival of prehistoric deposits in situ. No submerged prehistoric landscapes have been identified within the site boundary to date. Additionally, there is no evidence of peat or organic sediments within the site boundary, therefore, this suggests that there is low potential for paleo-landscapes, and any associated paleoenvironmental or archaeological material to be present within the site boundary. However, it is possible that isolated and residual finds may be found within deeply buried glacial deposits.

 

11.3.2 Maritime and aviation archaeology

  1. The UK has a long maritime history since at least the Mesolithic period. Wreck sites are a common feature around the entirety of the UK coast but specific knowledge of the maritime archaeology of the UK Continental Shelf (UKCS) is very low.
  2. The chronological periods and their corresponding date ranges that are considered in this Scoping Report are noted in Apx Table 11.3   Open ▸ . Dates are referred to as BC (Before Christ), or AD (Anno Domini).

 

Apx Table 11.3:
Overview of Scottish Archaeological Chronology

Apx Table 11.3: Overview of Scottish Archaeological Chronology

 

  1. No evidence of Palaeolithic maritime archaeology pre-dating the Devensian glacial maximum has been found in the UK due to glaciations, marine transgressions and fluvial activity. However, this lack of evidence does not infer that there was of a lack of maritime activity during the Palaeolithic around the UK. It is hypothesised that simple watercraft may have been used during this period, such as hide-covered logs or boat rafts, for coastal journeys or fishing (Wessex Archaeology, 2009).
  2. During the Neolithic and Bronze Age periods, evidence begins to appear to suggest the advent of maritime trade. In the UK, the only physical evidence for Neolithic maritime watercraft is logboats. However, it is hypothesised that the development of more complex logboats used at sea and, possibly, simple plank boats in inland waters may have occurred during the Neolithic period. No evidence for these craft has yet been found to date, however. Evidence from the Bronze Age, suggests that hide boats and sewn plank boats were being developed and used within the UK (Wessex Archaeology, 2009).
  3. During the Iron Age and Roman periods, evidence of more substantial maritime sailing and trading vessels being used within the UK was apparent. Trading between ports in the south of the UK and continental Europe (France and the Mediterranean) was recorded during these periods. Evidence of iron anchors from the 1st and 2nd-3rd centuries AD have been found in waters in the south-west of the UK, as well as logboats, plank-built boats and larger sea-going vessels (Wessex Archaeology, 2009).
  4. During the Early Medieval and Medieval periods, boat development became more local after the withdrawal of the Romans in the 5th century AD. Maritime craft from this period was influenced by Anglo-Saxon and Scandinavian settlers, with introduction of Scandinavian-style clinker-boats. Maritime trading routes between the UK and continental Europe expanded during the Medieval period, with the emergence of trading confederations, such as the Hanseatic League in North Germany and the Baltic. This expansion of shipping around UK waters also presented greater chances for maritime casualties. Throughout this period developments in shipbuilding technology improved the military function of ships, with guns and naval weapons being introduced on vessels. The carvel technique of flush planking in larger merchant vessels became more common in the 15th century AD. During the late medieval period the development of reliable navigation techniques and aids allowed ship owners to plan long oceanic voyages and travel greater distances, with vessels from Europe travelling first to the New World and to the Far East during this period. There is potential for remains of shipwrecks from this period to be present within the UKCS and are generally of high archaeological importance (Wessex Archaeology, 2009).
  5. After 1500 AD, global exploration and technological innovation continued. Cannons were used extensively on naval vessels, as well as some merchant vessels, and are often the most obvious indication of the presence of a wreck. By the mid-19th century AD, the advent of the steam engine, iron hulls and the screw propeller drove major transformations on ships and shipping, resulting in a huge increase in the volume of shipping traffic in the UKCS. Recording of losses became more accurate and complete in the 18th and 19th centuries AD, therefore, the ‘known’ archaeological resource across the extent of the UKCS for this period is greater than for earlier periods (Wessex Archaeology, 2009).
  6. The maritime archaeological record of the period from 1914 to the present is dominated by World Wars I and II. Warships, submarines, U-boats, merchant vessels (including cargo vessels, troopships and hospital ships), military and other aircraft, and smaller vessels and craft were lost during the World Wars, with new technologies of the submarine, torpedo, mine and aircraft mostly responsible for the huge toll in shipping losses, as well as the active destruction of shipping by all sides. Boats and ships continued to enter the archaeological record during the inter-war period and after 1945. Ships and boats are less numerous and prone to disaster since this period, however, the overall volume of trade by sea continues to be very high. The loss of big vessels continues to gain attention in the present day, particularly due to the threat of pollution, however, losses amongst smaller vessels such as fishing vessels tend to gain less notice (Wessex Archaeology, 2009).
  7. The survival of archaeological evidence of maritime activity within the UKCS is variable, but early remains have been found in relatively good condition. ‘Known’ maritime archaeology is skewed in favour of more recent wrecks due to better record keeping, more robust construction materials and methods, and shorter time on the seabed. However, there is potential for very ancient wrecks or materials to survive in archaeological contexts within the UKCS, and these sites are likely to be of substantial significance (Wessex Archaeology, 2009).
  8. ‘Known’ archaeological features within the site boundary are as follows:
  • no protected areas or statutory designations in relation to submerged landscapes within the limits of the site boundary;
  • no designated wrecks are recorded within the limits of the site boundary;
  • no wrecks or obstructions lie within the site boundary or marine archaeology study area as recorded by the UKHO ( Apx Figure 11.1   Open ▸ );
  • two wrecks were found during the initial geophysical survey ( Apx Table 11.5   Open ▸ ; Apx Figure 11.2   Open ▸ ); however, these are not recorded by the UKHO. One wreck (named as ‘Contact S_NM_B_0001’ within the geophysical survey report (Ocean Infinity, 2022b)) has been entered into the Canmore National Records of the Historic Environment (NRHE) database with ID number: 372595. The second wreck will be entered in to the NRHE database in the future. It is not known at present if either of these identified wrecks may align with the recorded losses noted below. A marine archaeology assessment of the geophysical data will be completed to gain further understanding of these wrecks and identify any further anomalies of archaeological interest.
  1. Recorded losses are maritime and aviation losses that are known to have occurred in the vicinity but to which no specific location can be attributed as positional data of these records is unreliable. However, they do provide information on the archaeological potential of the area. Recorded losses may be attributed to unknown anomalies identified by the geophysical survey or they may be positioned outside the marine archaeology study area (BEIS, 2022f). A total of four recorded losses are attributed to coordinates within the marine archaeology study area as recorded by the NRHE: Svein Jarl, Titan, Duva and Scottish Queen (Canmore, 2022; Apx Table 11.4   Open ▸ ).

 

Apx Table 11.4:
Recorded Losses Attributed to Coordinates Within the Marine Archaeology Study Area (Canmore, 2022)

Apx Table 11.4: Recorded Losses Attributed to Coordinates Within the Marine Archaeology Study Area (Canmore, 2022)

 

  1. The recorded maritime losses listed above are all iron and steel vessels dating from the 19th and 20th centuries. The prevalence of iron and steel wrecks in the record have the potential to mask the presence of earlier shipwrecks, which are of potentially greater archaeological interest. Wooden shipwrecks tend to be older and smaller, and tend to have carried less ferrous material, compared to iron and steel shipwrecks. They are less likely to be located by geophysical survey as wooden shipwrecks tend to degrade and break up more quickly than iron and steel wrecks and are therefore more likely to be scattered, dispersed, and have a generally lower physical profile on the seabed.
  2. These earlier wrecks are potentially the most archaeologically important and there will be an ongoing recognition of the potential to encounter currently unknown or unrecorded shipwrecks, and mechanisms put in place to ensure the prompt reporting and avoidance of undue damage to any such discoveries.

 

Apx Table 11.5:
Gazetteer of Maritime Archaeology Identified within the Initial Geophysical Survey (Ocean Infinity, 2022b)

Apx Table 11.5: Gazetteer of Maritime Archaeology Identified within the Initial Geophysical Survey (Ocean Infinity, 2022b)


Apx Figure 11.1:
Position of UKHO Records in the Vicinity of the Site Boundary

Apx Figure 11.1: Position of UKHO Records in the Vicinity of the Site Boundary

Apx Figure 11.2:
Location of Maritime Archaeology Identified Within the Initial Geophysical Survey

Apx Figure 11.2: Location of Maritime Archaeology Identified Within the Initial Geophysical Survey