Preservation of modern and MIS 5.5 erosional landforms and biological structures as sea level markers : a matter of luck?

The Mediterranean Basin is characterized by a significant variability in tectonic behaviour, ranging from subsidence to uplifting. However, those coastal areas considered to be tectonically stable show coastal landforms at elevations consistent with eustatic and isostatic sea level change models. In particular, geomorphological indicators—such as tidal notches or shore platforms—are often used to define the tectonic stability of the Mediterranean coasts. We present the results of swim surveys in nine rocky coastal sectors in the central Mediterranean Sea using the Geoswim approach. The entire route was covered in 22 days for a total distance of 158.5 km. All surveyed sites are considered to have been tectonically stable since the last interglacial (Marine Isotope Stage 5.5 [MIS 5.5]), because related sea level markers fit well with sea level rise models. The analysis of visual observations and punctual measurements highlighted that, with respect to the total length of surveyed coast, the occurrence of tidal notches, shore platforms, and other indicators accounts for 85% of the modern coastline, and only 1% of the MIS 5.5 equivalent. Therefore, only 1% of the surveyed coast showed the presence of fossil markers of paleo sea levels above the datum. This significant difference is mainly attributable to erosion processes that did not allow the preservation of the geomorphic evidence of past sea level stands. In the end, our research method showed that the feasibility of applying such markers to define long-term tectonic behaviour is much higher in areas where pre-modern indicators have not been erased, such as at sites with hard bedrock previously covered by post-MIS 5.5 continental deposits, e.g., Sardinia, the Egadi Islands, Ansedonia, Gaeta, and Circeo. In general, the chances of finding such preserved indicators are very low.peer-reviewe

Monitoring Coastal Erosion Using Remote Images: Comparison between Physically and Remotely Acquired Data on a Limestone Coast

Boulder-sized clasts on rocky coasts are considered as erosional signatures of extreme wave events and boulder attributes are often used in numerical models to estimate wave characteristics. The use of unmanned aerial vehicle (UAV) technology and related software has facilitated the monitoring of coastal areas, by generating models from which 2D and 3D measurements can be derived. However, the reliability and preciseness of such measurements is still to be determined. This study seeks to analyse the accuracy of boulder measurements by comparing the dimension data obtained through in-situ measurements with ex situ data generated from digital models, based on UAV images. The study area is a bouldered sloping coast located on the southeast coast of Malta (Central Mediterranean) that has developed into multiple limestone dipped strata with a fractured and heavily jointed morphology. The dimensions of c. 200 boulders in different morphological settings, such as clusters or ridges, have been statistically compared. The results show a very strong correlation between the two datasets, both in 2D and 3D; however some notable differences were observed at the individual boulder level. For the majority of boulders analysed, the A and B axes dimensions varied by ±10% to 20%. The C axis proved to be harder to measure accurately and showed a wider range of difference. Boulder volume results in the majority of cases varied from 0% to ±40%. Some tested methods of volume calculation may be more accurate and realistic than others depending on the boulder position in relation to other clasts and shore morphology. An automated digital analysis of the terrain surface to identify the boulder extents may offer possibilities for a more accurate estimation of boulder attributes

Durham University and its role in Malta's development planning during the 1950s through applied research

In the 1950s the University of Durham was involved in a number of separate externally-funded projects that were aimed at assessing Malta's potential for development after it became independent from the United Kingdom. Following a pilot study, a group led by W.B. Fisher of the Department of Geography together with a team from the University of Malta, obtained what at the time were substantial funds from the Colonial Office's Colonial Economic Research Committee (CERC). Concurrently K.C. Dunham, Head of the Department of Geology, successfully obtained support from British Petroleum to carry out a geological survey, while a soil survey was separately commissioned. As well as marking the first of what was to become an established tradition of applied development projects in the eastern Mediterranean and Middle East, the Durham Geography Department also used its growing profile of external funding to stimulate an expansion of both its teaching and its research, so as to become one of the largest departments in the United Kingdom. Reflecting the zeitgeist of the time, Fisher and his colleagues viewed applied research, not only as an academic exercise but also as a route to human betterment, and perceived the researchers' task as providing information and policy options upon which decisions makers may formulate policy. They eschewed any attempt to fully consider different development strategies. However, some younger researchers in their later outputs and doctoral theses adopted a more critical approach about the options for Malta's future. The principal issue raised by Durham team was a concern that post-independence Malta was facing a Malthusian trap in which the islands would not have a sufficiently productive resource base to support its growing population. Over the past six decades the trap has been avoided because of a growing economy, but today pressures of people on resources are once more acute and a case is made for a second land-use survey