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During the 19th century, remains of an ancient harbour were found underwater at a depth of 5 to 6 meters in the eastern port of Alexandria. A research program was undertaken to determine when the harbour of Alexandria submerged underwater. Data were collected through underwater surveys by scuba diving and by campaigns of corings on land. Geomorphological (i.e. notches and pebble beaches), archaeological (harbour structures), and biological (i.e. marine macrofauna, bioconstructions, and biodepositions) sea level indicators were correlated to understand changes in relative sea level during the last 6 millennia. For each proxy, the altitudinal (vertical) and chronological ranges of imprecision were discussed. The results indicate that the rate of the relative sea level rise is ~80 mm per century between the middle of the 6th millennium and the 5th‒6th c. AD. An abrupt relative sea level rise (3.5 m + 1.5 m) occurred during the mid 8th c. to the end of 9th c. A D. I n t he 8 th c. A D, a s imilar p henomenon was observed for Heracleion (25 km east of Alexandria). Thus, a wide movement of sinking affected in a synchronous manner the western coastal margin of the Nile delta. Since this 8th- 9th c. AD event, the subsidence has increased around 2 m. The role of abrupt sinking events and subsidence remain determining in the deltaic context to anticipate future coastal adaptations and the risk of submersion.

As the second most indented coast in the world, the Eastern Adriatic coast is locus typicus of Dalmatian type of coast. It is named after the landscape of Dalmatia (Croatia) where geomorphological and geological structures are parallel to the coast and island chains with channels separating them. It is formed by ingression of the rising postglacial sea after which the elevations of the former mountains (in accordance to general provision of the landforms) became islands in a row or elongated islands, and elongated valleys are submerged and are now channels. There are 79 islands, 525 islets, and 642 rocks and rocks awash, or a total of 1246 recorded. The total length of coastline is 5835 kilometers (length of the coastline of mainland is 1777 km of and length of the coastline of islands is 4058 km). Built up mostly by Mesozoic limestones, the coastlines of the eastern Adriatic show only very little forming by true littoral processes. Beaches are missing as well as extended cliffs (except the tectonic ones). The reason is prevalence of easily soluble carbonate rocks in the drainage area of rivers flowing into Adriatic Sea along eastern coast, with small discharge (only approximately 20% of river-born material is in suspended form) ; and count-clockwise sea-current circulation (that preserves the eastern coast from intensive input of suspended matter delivered by the Po River and Apennine rivers).

Located along the Adriatic coast, the Velebit Mt. is the largest mountain range in Croatia. As a part of extensive Dinaric karst region, it consists of a wide variety of stratigraphic units, ranging in age from Carboniferous to Quaternary. Structurally, Velebit Mt. represents an anticline built up predominantly of carbonate rocks. The best developed karst features occur in the Jelar-breccia unit. Intensely tectonic deformed Jelar-breccia represents development of Paleogene deposits in the Karst Dinarides. These massive or thick- bedded carbonate breccias are built mostly from square, poorly sorted carbonate clasts of various sizes. Matrix is carbonate, gray to reddish coloured, whereas stratigraphic composition and size of clasts varies. Due to highly complex composition and differences in the composition of clasts (in relation to matrix) selective corrosion of these deposits occurs. Selective corrosion is further increased by micro-tectonic cracks in Jelar- breccia, as a result of intense tectonic deformations after sedimentation. All of these properties lead to increased weathering of rock mass, which results in “unusual relief forms“ development. From the sea-level up to the mountain top various types of karst relief forms occur: furrow-like karren (locally called žlibe), fissure karren (locally called škrape), rinnenkarren or runnels (solution grooves), network karren, debrits karren (locally called grohot), meandering karren, kamenitzas (solution pans), karst wells, natural bridges (locally called prozorci), and biocorrosion pits.