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Shipwrecks are an integral part of our maritime archaeological landscape and are associated with diverse societal and cultural interests, yielding significant management challenges. Coupled hydrodynamic and geomorphological processes significantly impact the effective in situ preservation of these fragile sites. In this study, we assess sediment budget change and hydrodynamic triggers at metal‐hulled shipwrecks lost between 1875 and 1918, all located in the tidally dominated Irish Sea at depths between 26 and 84 m. This is conducted using time‐lapse, multibeam echosounder surveys at multiannual, annual, and weekly time steps, supported by sediment grain‐size analysis, modeled ocean currents, and shallow seismic data. Results indicate significant changes at all time steps for sites located in sand‐dominated environments, whereas the seabed around shipwrecks settled in multimodal sediments shows virtually no change outside of measurement errors (±30 cm). Variability in geomorphic change is attributed to local environmental factors, including bed shear stress, sediment supply, and spatial barriers to scour. We demonstrate that individual wrecks in similar shelf sea regions can be in very different equilibrium states, which has critical implications for the in situ management of underwater cultural heritage. [ABSTRACT FROM AUTHOR]

Inland waterways, such as rivers and lakes have been foci of human settlement and use for millennia. However, underwater archaeological prospection or survey in these environments is often hindered by poor or no-visibility conditions. While this can be overcome using a range of well-established geophysical techniques, their application in inland waterways seems comparatively less common than in offshore environments. Possible reasons include the logistical challenges of surveying shallow confined, often inaccessible and uncharted waters coupled with a wider lack of awareness of the submerged archaeological potential of inland waterways. This paper demonstrates one method by which the logistical challenge can be circumvented, specifically the use of low-cost acoustic systems which combine a single-beam echo sounder and sidescan sonar. These systems have appeared within the last decade and are smaller and cheaper than their survey-grade counterparts. Although developed for the sport fishing community, as shown here, they can also be used for archaeological purposes. Their effectiveness for archaeological prospection is illustrated via three case studies from lacustrine and riverine settings in Northern Ireland and by reference to object detection and bathymetric mapping. The data presented indicate that the low-cost systems are capable of collecting data that is sufficient for archaeological purposes but they are best suited to shallow confined waters where their disadvantages (limited range and depth of operation, reduced image quality) are minimized. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We present early to Mid-Holocene paleo-geographic reconstructions for the Ramore Head area (Northern Ireland). This coastal area is characterized by Mesolithic occupation (c. 10-6 ka) and preserved early-Mid-Holocene peats both on- and offshore. This paper improves on previous reconstructions by employing a backstripping methodology, which removes accumulated recent deposits from identified buried paleo-landsurfaces instead of using modern topography as an analogue to the past landscape. Paleo-landsurfaces are identified offshore from seismic profiles supplemented by cores, and onshore through legacy borehole records. The paleo-landsurface can be traced offshore to depths of −2 to −19 m and is buried by <5 m of modern sediment. It extends onshore under the coastal town of Portrush and is buried <2.5-10 m below modern ground level. The identified paleo-landsurface is combined with sea-level curves from recent Glacio-Isostatic-Adjustment models to reconstruct marine transgression during the early-Mid-Holocene. Comparison is also made with reconstructions based on modern topography. Together, the identified paleo-landsurfaces and revised reconstructions can assist future site prospection on- and offshore and delimit high-potential areas for heritage management. Revised reconstructions also allow placement of extant archaeology into a more accurate context of landscape change and help develop insights into local-scale site location patterns. [ABSTRACT FROM AUTHOR]