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This study presents a global overview of the submerged speleothems used to reconstruct paleo sea levels and reports new results from two stalactites collected in the Mediterranean Sea. Coastal cave deposits significantly contributed to the understanding of global and regional sea-level variations during the Middle and Late Quaternary. The studied speleothems cover the last 1.4 Myr and focused mainly on Marine Isotope Stages (MIS) 1, 2, 3, 5.1, 5.3, 5.5, 7.1, 7.2, 7.3 and 7.5. The results indicate that submerged speleothems represent extraordinary archives that can provide detailed information on former sea-level changes. The two stalactites collected in the central Mediterranean Sea, at Favignana and Ustica islands (Sicily, Italy), are both characterized by continental, phreatic or marine layers. The U-Th and 14C ages of the new speleothems provide results of great interest for relative sea-level changes over the last 1000 years.

In this paper we present and discuss data concerning the morphostructural evolution at Ustica Island (Tyrrhenian Sea, Italy) during Late Quaternary. New insights on the relative sea-level changes of Ustica are coming from data collected during a geomorphological field survey around the island, together with the bathymetric analysis of the surrounding seabed and 14C datings on samples of speleothems, flowstones and marine shells found inside three selected sea caves. The survey was mainly accomplished on June 2015 through the first complete snorkel investigation off the about 18 km-long volcanic coast of the island, which allowed to precisely define location, relationship and morphometric features of coastal landforms associated with modern sea level. This study highlights the occurrence, for the first time in the Mediterranean, of tidal notches in correspondence of carbonate inclusions in volcanic rocks. The elevation of the modern tidal notch suggests that no significant vertical deformations occurred in the southeastern and eastern sectors of Ustica in the last 100 years. However, the presence of pillow lavas along the coast demonstrates that Ustica was affected by a regional uplift since the Late Quaternary, as also confirmed by MIS5.5 deposits located at about 30 m a.s.l., which suggests an average uplift rate of 0.23 mm/y. Radiocarbon dating of fossil barnacles collected inside the Grotta Segreta cave indicate an age of 1823 ± 104 cal. BP. The difference in height with respect to living barnacles in the same site suggests that their present elevation could be related to stick-slip coseismic deformations caused by the four earthquake sequences (two of which with Mw = 4.63 ± 0.46) that strongly struck the island between 1906 and 1924. © 2017 Elsevier B.V.

The tidal notch and the sea caves which cut into the Namigata Limestone is stiuated in 240m above sea level, Ibara City. The notch assocciates the Namigata Terrace 200m to 240m high. These geomorphological features indicate an event of high sea level. However the age of the event has not been known.

There are many caves along Shimane Peninsula coast, and they are considered sea caves. Some of them were used by the ancient people for dwellings or other purposes, and remain as the archaeological sites. These cave sites are located facing the coastal line, so it is considered that the ancient people who used the cave sites were influenced by the sea level changes or other enviroumental changes. And for these reasons, researches of the cave sites contribute to not only archaeological studies but also palaeo-environmental studies and so on. With these aims, we planed the excavation of the cave sites, and carried out the research at Sarugahana Todai cave site, Mihonoseki town, Shimane prefecture, in 1995, 1996 and 1997 (Takehiro and Watanabe et al., 1996 ; Takehiro and Ege et al., 1997 ; Takehiro and Watanabe et al., 1998). In 1998, we carried out the 2nd excavation of Sarugahana Todai cave site and the trial excavation of Location rock shelter, 15 m west of the cave site. In the 2nd excavation of this cave site, we excavated about 2.5 m^2 range in the front of the cave site, and reached about 0.9 m above the sea level. As one of the result of this excavation, we could find occupied surface around 1.2-1 m above the sea level, which is thought to belong to the later part of the early stage of the Jomon period or the former part of the middle stage of it, ca. 5,500 - 4,500 uncal. y. B .P.. And these date of occupation at this cave site are one of the oldest example of occupation in the cave sites at Shimane Peninsula at present. We could get the important data to research the problem about the date of the Jomon marine transgression, and so on. In the trial excavation of Location rock shelter, we excavated about 2 m^2 range at the inner part of rock shelter. We found the occupied surface at 1 m depth below the present surface. And we found the archaeological remains of the Jomon and Yayoi periods.

There are many caves along Shimane Peninsula coast, and they are considered sea caves. Some of them were used by the ancient people for dwellings or other purposes, and remain as the archaeological sites. These cave sites are located facing the coastal line, so it is considered that the ancient people who would use or used the cave sites were influenced by the sea level changes or other environmental changes. And for these reasons, researches of the cave sites contribute to not only archaeological studies but also palaeo-environmental studies and so on. With these aims, we planned the excavation of the cave sites, and carried out the excavation at Sarugahana Todai cave site, Mihonoseki Town, Shimane Prefecture, in 1995 and 1996 (Takehiro and Watanabe et al., 1996 ; Takehiro and Ege et al., 1997). In 1997, we researched the Location rock shelter, 10 m west of Sarugahana Todai cave site. In this location we found some archaeological remains, Jomon potsherd, obsidian flakes and so on, in 1996's research. This location was probably thought to be the archaeological site, and we carried out a preliminary survey at this location. Judging by the present data, the rock shelter at this location is thought to be formed by the ancient marine erosion, and to be used for the dwelling or other purposes. And this rock shelter is thought to have suffered the marine erosion or other influences continuously after the emergence of the initial shape, so there is also the possibility that the initial shape of this rock shelter was the different form, for example, sea cave and so on. To study f'urther the significance of this location, we need to do more future researches.

There are many caves along Shimane Peninsula coast, and they are considered sea caves. Some of them were used by the ancient people for dwellings or other purposes, and remain as the archaeological sites. These cave sites are located facing the coastal line, so it is considered that the ancient people who would use or used the cave sites were influenced by the sea level changes or other environmental changes. And for these reasons, researches of the cave sites contribute to not only archaeological studies but also palaeo-environmental studies and so on. With these aims, we planed the excavation of the cave sites, and carried out the trial excavation at Sarugahana Todai cave site, Mihonoseki town, Yatuka gun, Shimane Prefecture, in 1995. In 1996, we carried out the first excavation at Sarugahana Todai cave site. This cave site is located facing the coastal line between Lake Nakaumi and Sakai Channel. The cave is opened about 4 m above the sea level at present, but the initial bottom of the cave is still unknown, because it is covered with the sediments which have been formed after the emergence of the initial cave. In this 1996s' excavation, we excavated about 10m^2 range of the cave site, and reached about 65cm above the sea level at the deepest excavated point, and we did not reach the initial bottom of the cave yet. As one of the result of this excavation, we could find the surface which is thought to be occupied at a certain time of the Jomon period(possibly the late stage of it), and its level is around 2.4m above the sea level at the south end of the trench. And we think there are more occupied surfaces under this surface. To study further this site and the other cave sites at Shimane Peninsula, we have to carry out more researches.

There are many caves along Shimane Peninsula coast, and they are considered the sea caves. Some of them were used by the ancient People for dwellings or other purposes, and remain as the archaeological sites. These cave sites are located facing the coastal line, so it is considered that the ancient People who would use or used the cave sites were influenced by the sea level changes or other environmental changes. And for these reasons, researches of the cave sites contribute to not only archaeological studies but also palaeo-environmental studies and so on. With these aims, we carried out a trial excavation at Sarugahana Todai cave site, Mihonoseki town, Yatuka gun, Shimane prefecture, and found archaeological materials of the Jomon period.

The Otranto–Leuca coastal tract is marked by the presence of numerous sea caves placed close to present sea level. They are located generally at the back of a shore platform covered by a sequence of breccia deposits, marine sediments and speleothems. At Grotta di Masseria dell'Orte, marine cemented sands rest on a narrow shore platform at about 6.2 m above mean sea level and are covered by speleothems older than 185 ka. At Grotta del Diavolo, which is mostly filled by breccia deposits, three beach levels have been detected at about 3.0, 3.5 and 5.9 m above msl. They are either covered by or overlie speleothems that yield an U/Th age of 340, 78 ka and between 170.3 and 146.5, respectively. Geomorphological evidence and radiometric ages indicate that the area after a period of uplift has been tectonically stable since the last part of the Middle Pleistocene so that marine landforms close to the present shoreline underwent a polycyclic evolution. The sedimentary fills of sea caves formed during Middle-Late Pleistocene glacial stages, when arid or semiarid conditions promoted the removal of regolith and the development of thick breccia deposits. During Marine Isotope Stages (MIS) 9.3, 5.5 and 5.1, cave sediments were partially eroded whereas beach layers and related speleothems developed. These are, in fact, the only marine isotope stages marked by a sea level position which in this Mediterranean region was either close to, or slightly higher than, the present one.

Several sets of staircased Quaternary marine deposits can be observed along the Gibraltar coast ranging from 1 to 210 m above the present mean sea level. Geomorphological mapping establishes, from the relationship between shore, scree and dune sedimentary formations, five main morphotectonic steps on the Rock: marine terraces between 1 and 25 m, 30-60 m, 80-130 m, 160-210 m, and above. Each terrace level and its shore linked morphologies is backed by a steep relict sea cliff with sea caves and notches along its landward margin. Staircased sea cave levels are representative of Quaternary hightstand position. Inside the caves remains of both notch and boring levels are found. We have distinguished three main sea cave levels at the Eastern flank of the Rock: A, at present sea level; B, +55 m; C, +180 m.

Several sets of staircased Quaternary marine deposits can be observed along the Gibraltar coast ranging from 1 to 210 m above the present mean sea level. Geomorphological mapping establishes, from the relationship between shore, scree and dune sedimentary formations, five main morphotectonic steps on the Rock: marine terraces between 1 and 25 m, 30-60 m, 80-130 m, 160-210 m, and above. Each terrace level and its shore linked morphologies is backed by a steep relict sea cliff with sea caves and notches along its landward margin. Staircased sea cave levels are representative of Quaternary hightstand position. Inside the caves remains of both notch and boring levels are found. We have distinguished three main sea cave levels at the Eastern flank of the Rock: A, at present sea level; B, +55 m; C, +180 m.