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SCIENTISTS have identified a massive underwater bulge rising 200m above the surrounding sea- bed between Malta and the Italian island of Pantelleria. The bulge situated between 60km and 80km west-northwest of Malta, provides new evidence of tectonic movement in the cen- tral Mediterranean. The structure stretches for 26km in length and 4.6km in width. It lies at depths of between 1,400m and 1,750m in the north- ern sector of the Malta Graben. The Malta Graben is an under- water rift valley formed when sections of the earth's crust pulled apart and sank, creating a deep trench on the seabed. The findings were published in the scientific journal Tectono- physics in a study titled: The Lo- cal Effects Of Large Plate Conver- gence: Africa-Europe Movements And The Recent Escape Tectonic Of The Malta Graben In The Sic- ily Channel. The research was led by Nicolò Chizzini of Italy's National Insti- tute of Geophysics and Volcano- logy and the University of Parma, alongside an international team of scientists from Italian and French research institutes. Not underwater sediments The researchers mapped the structure by combining bathym- etric surveys, which measure the depth and shape of the seabed, with seismic reflection profiles that use sound waves to investi- gate geological layers beneath the ocean floor. Previous interpretations had suggested that the feature could be a sedimentary deposit formed by underwater currents. Howev- er, seismic imaging revealed that the underlying rock layers are themselves bent and faulted up- wards, indicating that the bulge is a geological structure rather than simply an accumulation of sedi- ment. The findings point to a process known as positive structural in- version, whereby faults original- ly associated with the stretching and sinking of the earth's crust are subsequently reactivated un- der compressive forces, pushing geological layers upwards. The Malta Graben was original- ly formed through the stretching of the earth's crust. However, parts of this underwater structure have subsequently been reshaped by the convergence of the Afri- can and Eurasian tectonic plates. The African Plate is moving north-northwest towards Europe at an estimated rate of around five millimetres a year, generating stresses across the central Medi- terranean and driving complex movements along regional fault systems. Same fault system shapes Malta and Gozo One of the study's most inter- esting findings is the geological relationship between the Malta Graben and the Malta-Gozo ba- sin, the underwater depression separating the two islands. The researchers argue that the two structures, although formed along distinct fault segments, are part of a single regional system characterised by right-lateral movements of the earth's crust, accompanied by stretching. This type of movement is known as dextral transtension. The geological framework around the Maltese islands is controlled by two main genera- tions of faults. An older system, running broadly east-northeast to west-southwest and dating back to the Early Miocene (around 23 to 16 million years ago), is respon- sible for the raised and sunken blocks that give the islands much of their characteristic geological structure. A younger system, running northwest to southeast and dat- ing from the Late Miocene to Early Pliocene (around 11.6 to 3.3 million years ago), generated sideways movements along faults accompanied by crustal stretch- ing. The researchers link this younger system to the formation of the Malta-Gozo basin. Earthquake recordings in the area independently confirm right-lateral movements accom- panied by an extensional compo- nent, supporting the interpreta- tion that the Malta Graben and the Malta-Gozo basin are inter- connected parts of a wider tec- tonic corridor. The researchers describe the Malta Graben as the main struc- tural expression of this region- al movement, while the smaller Malta-Gozo basin represents a more peripheral part of the same system. Malta's geological setting The findings provide further insight into the geological forces shaping the Maltese islands and surrounding seabed, where the interaction between the African and Eurasian plates produces a complex pattern of fault move- ments. Understanding how these faults move and are reactivated is im- portant for assessing regional seismic activity and geological hazards. The study also contrib- utes to understanding the geolog- ical evolution of the Sicily Chan- nel, including the role of deep fractures in the movement of magma through the earth's crust. The identification of substantial deformation beneath the seabed is also relevant to understanding ground stability in an area crossed by submarine infrastructure, in- cluding telecommunications ca- bles and energy interconnectors. 9 maltatoday | SUNDAY • 8 NOVEMBER 2026 NEWS Scientists find 200m seabed bulge linked to Malta-Gozo fault system JAMES DEBONO jdebono@mediatoday.com.mt Study in Tectonophysics identifies a massive underwater structure between Malta and Pantelleria and links its formation to the same regional tectonic system responsible for the Malta- Gozo basin The researchers mapped the structure by combining bathymetric surveys, which measure the depth and shape of the seabed, with seismic reflection profiles that use sound waves to investigate geological layers beneath the ocean floor