A report on the magnetometer survey results off the north-eastern coast of Malta 2010-2014: Mellieħa Bay, Salina Bay, and St Paul’s Bay (original) (raw)
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Revisiting the Mellieħa Bay Wreck: A report on two seasons of survey and excavation (2013-2014)
Malta Archaeological Review, 2021
The Mellieħa Bay wreck is a third-century AD Roman shipwreck located in a bay on the northern coast of the island of Malta (Fig. 1). Recent excavations of the site were carried in 2013 and 2014 as part of 2 three-week underwater field schools, organised by the Department of Classics and Archaeology at the University of Malta. Both seasons were supported by the Honor Frost Foundation, whose mission is to 'promote the advancement and research, including publication of marine and maritime archaeology with particular focus on the eastern Mediterranean' (The Foundation, 2020). The site of Mellieħa Bay was originally selected due to its archaeological potential, based on the preliminary investigations conducted by Honor Frost in the late 1960s. The objective of this report is to present the results of the recent investigations of the Mellieħa Bay wreck, viewed within the context of Frost's 1967 excavation and survey of the site. The wreck is located in shallow waters towards the middle of the bay, situated to the southwest of a reef. The site lies approximately 700 m from the shore, at a maximum depth of 14 m (Fig. 2). It is surrounded by large meadows of Poseidonia oceanica. This sea-grass is highly protected and grows on bedrock, sand or on mattes. From a maritime perspective, Mellieħa Bay would have been an ideal landing place, offering good anchorage during unfavourable offshore winds to vessels. However, the reef would have posed a threat to any vessel wanting to anchor closer to shore. The bathymetry of the seabed is constantly changing, as attested by the large meadows of Poseidonia oceanica within the bay. Poseidonia mattes consist of layers composed mainly of dead Poseidonia leaves and rhizome deposits of dead sea-grass. On average Poseidonia mattes increase in height by about 1cm per annum (Frost 1969, 31). The current mattes are about 4 m in height, making these approximately 400 years old. During the This report focuses on the Mellieħa Bay wreck, a third-century Roman shipwreck first investigated by Honor Frost in the late 1960s. In 2013 and 2014 field schools organised by the University of Malta with the support of the Honor Frost Foundation sought to uncover what remained of the wreck, including any material culture still present. It also sought to investigate the site formation processes. A magnetometer survey revealed the location of a number of target anomalies. It could be determined that the wreck area is highly dynamic, with the scattered nature of the finds reflecting a high-energy zone, which periodically exposed the objects on the seabed. Between 2013 and 2014 it was noted that material remains were re-deposited in the wreck area over the winter months. The growth of Poseidonia oceanica eventually stabilised the site, and the location of recovered finds at the bottom of Poseidonia mattes points towards the high potential of material evidence still located within or under the mattes, as revealed in the magnetometer survey. The recovered material culture points towards a culturally homogenous site with all objects dating to the third century AD.
Developing magnetometer techniques to identify submerged archaeological sites
Camidge, K., P. Holt, C. Johns, L. Randall & A. Schmidt 2010. Developing magnetometer techniques to identify submerged archaeological sites (5671 DT). Historic Environment Service, Environment and Heritage, Cornwall County Council Report No: 2010R012. , 2010
Marine magnetic surveying has become a standard technique for mapping the location of ferrous material on the seabed. Existing guidance documents are concerned principally with data collection methods. The aim of the project was to acquire a better understanding of magnetic data and thus develop our ability to interpret these data with increased confidence.
The Shipwrecks of Xlendi Bay, Gozo, Malta
International Journal of Nautical Archaeology, 2013
Xlendi Bay, Gozo, Malta, is a rich underwater site. It was discovered in 1961 by British Navy divers on a training mission. Since then, a significant number of artefacts has been retrieved but not well studied. This paper summarizes a recent detailed study of the archaeological material and describes five amphora types that have not yet been identified. It also takes deep-water surveys that have recently been conducted by various teams into consideration.
A review of the Pleistocene Deposits in the Southwestern Coast of Malta
The various cave-fissure and coastal deposits described along the Southwestern coast of Malta have been shown to have had a fossil repertoire which corresponds with the 2nd faunal association described from Sicily dated to circa 455 ± 90 ka and the 3rd Sicilian faunal association dated to circa 200 ± 40 ka. The latter probably corresponds to the Gliridae-Hippopotamus Assemblage Biozone of Ghar Dalam Cave in Malta.
Over 400,000 shells of different calibers were dumped in Burgas Bay after the end of WWI. The operation, under the coordination of the British forces, was completed without the dumping areas to be clearly mentioned and mapped, allowing us today to assume that they can be anywhere in Burgas Bay. Many other shells were also dumped in the sea at the end of WWII. During the first phase of expansion of Burgas harbor, carried out between 2001 and 2006, a great deal of unexploded ammunition, originating from both WWI and WWII, was discovered and recovered by the dredging operations. Prior to the start of the second expansion phase, the Burgas port authorities ordered a detailed geophysical search to be carried out and cover a 90,000 sq.m surface where dredging activities are planned, aiming to identify sites where items such as UXO, wrecks, pipes, anchors and other metal objects lying on the sea floor and/or buried in shallow sediments could disturb and even endanger the dredging. The high-resolution marine magnetic mapping carried out in August 2016 by a team comprising both Romanian and Bulgarian specialists entirely covered the area of interest. The search was conducted in a totally unfriendly magnetic environment, dominated by huge variations of the total geomagnetic field due to the numerous outcropping or shallow intrusions of Paleozoic and Late Cretaceous ages, to lens of “black sands” with high contents of titanomagnetite minerals, resulted from the physical decomposition of the magmatites and not least to the large pile of steel pipeline sections stored on the neighboring quay. Still, the careful analysis of the magnetic analytic signal as well as the individual analysis of each marine magnetic line were able to highlight the presence of over 75 potential target areas where the presence of UXO-type items, possibly dumped or lost ferrous objects, accumulations of ammunition, etc. on the seabed or shallowly buried in sediments was highly likely. The indexed target sites became subsequently subject for scuba diving inspection which confirmed the existence of ferrous objects within all selected sites and brought to surface over 2,000 artillery shells and other items.
EGU General Assembly Conference Abstracts, 2016
Magnetic properties of deposits around the shipwrecks ("Munin" and "Abille") in the Gulf of GdaĔsk were investigated. Values of magnetic susceptibility (Ȥ) are relatively low; however, they reveal significant differences between investigated sites. The values of Ȥ around "Abille" wreck were 5-8×10-8 m 3 /kg. Around "Munin" wreck results were more diversified reaching value of Ȥ between 3.07×10-8 m 3 /kg and 12.92×10-8 m 3 /kg. The spatial variability of Ȥ coincided with near-bottom water currents distribution in the Gulf of GdaĔsk. Magnetic minerals were identified by thermomagnetic analysis. Around "Abille" wreck we have found magnetite with small amount of maghemite or hematite. The "Munin" sediments include only one magnetic phase; in several samples it is magnetite, in the others-maghemite. Day-Dunlop plot shows that "Abille" set is shifted towards lower magnetization ratio and higher coercivity ratio. The correlation between the distribution of Ȥ and hydrodynamic condition around shipwrecks allows to determine the direction of contaminant transport.