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Understanding millennial changes in relative sea level (RSL) and coastal responses in stable regions is crucial for deciphering the intricate relationship between natural dynamics and human adaptation. This interdisciplinary study explores the interplay between mid-to-Late Holocene sea-level fluctuations and tectonic along the mid-Tyrrhenian coast. The study area, located between the Fondi and Garigliano coastal plains, held great significance in ancient times. In particular, the strategic role of Formia, a monitoring point for the Tyrrhenian Sea, made this city one of the most important commercial hub during Roman occupation, leading to a significant urbanization of the coastal stretch testified by well-preserved remains nowadays scattered along the submerged or semi-submerged coastal sectors. This study reconstructs the mid-to-Late Holocene morpho-evolution and RSL changes in the study area by creating a geodatabase made of 52 sea-level markers (SLMs) derived from direct geoarchaeological measurements, stratigraphic and palaeoecological interpretations of new borehole data, and previously published stratigraphic data. Specifically, the radiocarbon dating of three peat samples provided new data ranging between 7.62 ± 47 and 1.00 ± 51 ka BP on the sea level history in the area. Based on our dataset, between 9.0 and 8.0 ka BP, the sea level rose from −19 m to −6.5 m at a rate of about 15.6 mm/y, slowing to 0.8 mm/y afterwards, stabilizing at its current position. Results suggest that during the 1st century BC, local sea level was no higher than −0.55 ± 0.29 m. The collected RSL data support the hypothesis of tectonic stability of this sector during the last 2.0 ka, testified by the position of the SLMs in accordance with the glacio-hydro-isostatic adjustment (GIA) models and supported by the determination of average vertical ground movement rates of −0.017 ± 0.23 mm/y. Finally, in terms of coastal changes the overlay between new data from geoarchaeological surveys, reinterpretation of previously-published stratigraphic data, and geomorphological analysis allowed us to deduce a general coastal progradation trend in the historical time for both low-lying and rocky sectors, due to natural and anthropogenic forcing factors. [ABSTRACT FROM AUTHOR]

Enderby Land in East Antarctica and its adjacent areas, which are closely related to the Indian Plate in their geological evolution, have become one of the key zones for studies on how the Antarctic continent evolves. Based on the isostasy and flexure theories of the lithosphere and using the CRUST1.0 model as the depth constraint, this paper uses the gravity field model EIGEN-6C4 and topographic data to calculate the isostatic gravity anomalies of Enderby Land and its adjacent areas. Then, the crustal thickness of the study area is calculated, and three comprehensive geophysical interpretation profiles that vertically span the study area are plotted. The results show that the flexural isostatic gravity anomalies in Enderby Land and its adjacent areas are closely related to the regional tectonic setting, and the anomalies in different regions differ substantially, ranging from −50×10−5 m/s2 to 85×10−5 m/s2. A zone of high isostatic gravity anomalies (30×10−5−80×10−5 m/s2) is distributed outside the Cooperation Sea and Queen Maud Land, which may be plate remnants generated by early rifting. Except for the Kerguelen Plateau, which was formed by a hotspot and has a crustal thickness of 15 km, the thickness of the oceanic crust in other parts of the study area changes slightly by approximately 4–9 km, with the thinnest part being in Enderby Basin. The thickness of the inland crust along the coastline increases with the elevation, with the maximum thickness reaching 34 km. The isostatic gravity anomalies corresponding to the zone of high magnetic anomalies along the continental margin of Queen Maud Land are negative and small, with an isostatic adjustment trend indicating Moho surface uplift, and those on the edge of central Enderby Land are near zero, approaching the isostatic state, which may be caused by the magmatism at the early stage of rifting. The continental-oceanic boundary should be close to the contour line of the crustal thickness 10–12 km on the outer edge of the coastline. [ABSTRACT FROM AUTHOR]

Summary: The Moho interface depths and variations provide important references to understanding the outward growth and expansion mechanisms of the Tibetan Plateau, which have drawn much attention. Here, we constrain the Moho variations beneath the northeastern Tibetan Plateau (NETP) by using multiple geodetic data and climate models. Hydrological and tectonic gravitational signals are identified from multisource data and removed from the satellite gravity observations. Moreover, the mass variation rate, resulting from vertical Moho changes is calculated. The result shows that the mass variation rate due to the Moho changes is 1.3 ± 0.6 mm/yr (equivalent water height) within the NETP, which corresponds to a Moho uplift rate of 2.7 ± 1.3 mm/yr. Additionally, we calculate the tectonic Earth surface uplift rate from GPS and leveling observations with loading and GIA (glacier isostatic adjustment) influence corrected, which gives an uplift rate of 2.2 ± 0.1 mm/yr and is similar with the Moho uplift rate. Our results indicate that the crust in the NETP is uplifted with a slight decrease in crustal thickness. Combined with the lithospheric structure from seismological tomography studies, we suggest that the crustal uplift of the NETP is mainly caused by isostatic adjustment since the delamination of the thickened lithosphere. Plain Language Summary: The Northeastern Tibetan Plateau (NETP) is the front part of an inland expansion of the Tibetan Plateau, and the surface deformation and lithospheric structure in the NETP have attracted wide attention. Up to now, the study of static lithospheric structure is the main method to research the crust‐mantle tectonic movement in the NETP. Mass transfer in the crust and mantle can induce gravity changes. We retrieve the gravity signals caused by Moho changes based on multiple geodetic observations and climate models. We estimated the Moho interface changes rate and the Earth surface vertical deformation based on the gravity changes caused by the Moho interface as well as the GPS/leveling observations. The results indicate that the crust in the NETP is uplifted, which is mainly controlled by isostatic adjustment after delamination of the thickened lithosphere. This finding is helpful to further investigate the mechanisms of material migration of the Tibetan Plateau. Key Points: Hydrological and tectonic gravitational signals in the Northeastern Tibetan Plateau are identified from multi‐source dataObvious positive gravitational signals appeared in the Northeastern Tibetan Plateau suggest material accumulation in this areaUplift rates of the Moho and Earth's surface and the crustal thickness in the Northeastern Tibetan Plateau are estimated [ABSTRACT FROM AUTHOR]

Macaronesia is a complex oceanic region spanning three tectonic plates in the northeast Atlantic ocean. It is composed of four archipelagos, widely distributed and limited to the east by the Iberian Peninsula and north-western coast of Africa. This study aims to clarify recent Macaronesian kinematics from 19 GNSS stations located on the four archipelagos and the Iberian and African coastlines. The analysis is based on nearly 15 years of common data acquisition and aimed to detect new effects of intraplate tectonics or similar local/regional events consistent with calculated ground displacements. Evaluating the GNSS stations residual velocities relative to those expected from the NNR-MORVEL56 model, higher residuals were found at continental coastal stations (Africa) than at oceanic ones (Canaries and Madeira). From the computed strain rate map, the possible existence of a shear zone connecting the Gloria and Transmoroccan fault systems, already mentioned by other authors, was depicted. Cluster statistical analysis of the horizontal residual velocities helped to identify tectonic boundaries in Macaronesia and four groups of analogous intraplate residual velocities within this region. Three of four groups were identified in the Azores, highlighting the African-Nubian-Eurasian diffuse plate boundary in this region. Furthermore, in the Canary Islands, two distinct kinematic behaviours were detected, possibly due to the activity along a previously detected tectonic fault between Tenerife and Gran Canaria, where some stations have similar intraplate residuals to those at Madeira and Cape Verde stations, while others have similar intraplate residuals to those of continental stations. Finally, all stations on oceanic crust, except Cape Verde, present recent ground subsidence which may be attributed to isostatic adjustment. [ABSTRACT FROM AUTHOR]

Abstract The sea-level curve during the last deglaciation is characterized by two episodes of rapid sea-level rise, termed Meltwater Pulses (MWPs) 1A (14.6–14.3 kyr BP) and 1B (11.45–11.1 kyr BP), as well as an episode of relatively slow sea-level rise during the Younger Dryas stadial (YD; 12.85–11.65 kyr BP). However, the relative sea-level changes during the YD and MWP-1B periods are still not well defined. Here, we use precisely dated intertidal sediments derived from 6 sediment cores on the tectonically stable continental shelf of the East China Sea (ECS) to reconstruct a high-resolution sea-level curve between 14.0 kyr BP and 10.0 kyr BP. Although linear regression analysis suggests that the sea level rose continuously, with an average rate of 10.6 ± 0.6 mm/yr (r = −0.87, p(a) < 0.01, n = 95), the mode of sea-level rise differs before, during, and after the YD stadial. A rapid sea-level rise of 30.5 ± 4.9 mm/yr (r = −0.79, p(a) < 0.05, n = 25) occurred during 14.0–12.85 kyr BP. Subsequently, the rate of sea-level rise decreased significantly in response to the YD stadial, and it increased smoothly to 12.0 ± 1.4 mm/yr (r = −0.86, p(a) < 0.01, n = 29) from 11.65–10.0 kyr BP, indicating that MWP-1B was absent on the ECS shelf. Furthermore, based on comparisons of these data with other high-resolution curves of sea level or elevation at different latitudes, we suggest that the poleward seawater migration from intertropical broad oceans occurred because glacial isostatic adjustment could have generated a relatively consistent global sea-level height during the last deglaciation, especially during the YD, when the rate of sea-level rise was slowed. Highlights • Sea-level rise is constrained by East China Sea intertidal sediments. • A possible rapid sea-level rise occurred during 13.6–13.0 kyr BP. • Sea-level rise slowed remarkably in response to the Younger Dryas. • Meltwater Pulse 1B is not recorded on the East China Sea shelf. • The poleward migration of seawater can lead to global sea levels remaining the same. [ABSTRACT FROM AUTHOR]

Abstract A recent suite of Relative Sea-Level (RSL) data for the past 12 ka BP has provided new insights into the sea-level histories of the western Mediterranean region. Our analysis of the chronostratigraphic context of sea-level indicators from Spain (Catalonia, the Balearic Islands and the Gulf of Valencia), France (Corsica Island) and Italy (Sardinia Island) has yielded 162 new sea-level index and limiting points. These data have considerably enhanced previous RSL compilations, in addition to improving the quality of spatio-temporal sea-level reconstructions and our capacity to estimate isostatic-related vertical motions in the western Mediterranean basin. The glacial and hydro-isostatic adjustment (GIA) pattern elucidated by the new database shows discrepancy with respect to those predicted by the available GIA models. In particular, the new results underscore a non-coherent isostatic response of the central portion of the western Mediterranean, with the Balearic Islands manifesting significant departures from the sea-level histories of Corsica, Sardinia and, more generally, along most of the western Mediterranean coast. Our results are a crucial contribution to defining both the pattern and the magnitude of the isostatic signal along the western Mediterranean coast. In fact, vertical isostatic motions represent a key to better assess any possible post-industrial acceleration in sea-level rise and to define future scenarios of coastal inundation in the context of global change. Highlights • Recent studies in the western Mediterranean yielded 163 new sea-level datapoints. • We reconstruct the sea-level evolution along the Spanish coasts, Corsica and Sardinia. • We outlined a non-coherent isostatic response of the bulk of the basin. • The Balearic Islands manifested a significant departure from the GIA models. • We better defined the maximal magnitude of the isostatic signal in the Mediterranean. [ABSTRACT FROM AUTHOR]

We present a computational framework that allows investigating the Thermo-Hydro- Mechanical response of a representative part of a sedimentary basin during a glaciation cycle. We tackle the complexity of the problem, arising by the mutual interaction among several phenomena, by means of a multi-physics, multi-scale model with respect to both space and time. Our contribution addresses both the generation of the computational grid and the algorithm for the numerical solution of the problem. In particular we present a multi-scale approach accounting for the global deformation field of the lithosphere coupled with the Thermo-Hydro-Mechanical feedback of the ice load on a representative part of the domain at a finer scale. In the fine scale model we also include the erosion possibly caused by the ice melting. This methodology allows investigating the evolution of the sedimentary basin as a response to glaciation cycle at a fine scale, taking also into account the large spatial scale movement of the lithosphere due to isostasy. The numerical experiments are based on the analysis of simple scenario, and show the emergence of effects due to the multi-physics nature of the problem that are barely captured by simpler approaches.

A review of 917 relative sea-level (RSL) data-points has resulted in the first quality-controlled database constraining the Holocene sea-level histories of the western Mediterranean Sea (Spain, France, Italy, Slovenia, Croatia, Malta and Tunisia). We reviewed and standardized the geological RSL data-points using a new multi-proxy methodology based on: (1) modern taxa assemblages in Mediterranean lagoons and marshes; (2) beachrock characteristics (cement fabric and chemistry, sedimentary structures); and (3) the modern distribution of Mediterranean fixed biological indicators. These RSL data-points were coupled with the large number of archaeological RSL indicators available for the western Mediterranean. We assessed the spatial variability of RSL histories for 22 regions and compared these with the ICE-5G (VM2) GIA model. In the western Mediterranean, RSL rose continuously for the whole Holocene with a sudden slowdown at ~ 7.5 ka BP and a further deceleration during the last ~ 4.0 ka BP, after which time observed RSL changes are mainly related to variability in isostatic adjustment. The sole exception is southern Tunisia, where data show evidence of a mid-Holocene high-stand compatible with the isostatic impacts of the melting history of the remote Antarctic ice sheet. Our results indicate that late-Holocene sea-level rise was significantly slower than the current one. First estimates of GIA contribution indicate that, at least in the northwestern sector, it accounts at least for the 25–30% of the ongoing sea-level rise recorded by Mediterranean tidal gauges. Such contribution is less constrained at lower latitudes due to the lower quality of the late Holocene index points. Future applications of spatio-temporal statistical techniques are required to better quantify the gradient of the isostatic contribution and to provide improved context for the assessment of 20th century acceleration of Mediterranean sea-level rise. [ABSTRACT FROM AUTHOR]

Geological maps of South Carolina, covering >6800km², confirm the existence of eight preserved Pleistocene shorelines above current sea level: Marietta (+42.6m), Wicomico (+27.4m), Penholoway (+21.3m), Ladson (+17.4m), Ten Mile Hill (+10.7m), Pamlico (+6.7m), Princess Anne (+5.2m), and Silver Bluff (+3m). Current geochronologic data suggest that these eight shorelines correlate with Marine Oxygen Isotope Stages (MIS) as follows: Marietta-older than MIS 77; Wicomico-MIS 55-45; Penholoway-MIS 19 or 17; Ladson-MIS 11; Ten Mile Hill-MIS 7; Pamlico-MIS 5; Princess Anne-MIS 5; and Silver Bluff-MIS 5 or 3. Except for the MIS 5e Pamlico, and possibly the MIS 11 Ladson, the South Carolina elevations are higher than predicted by isotope proxy-based reconstructions. The <4m of total relief from the Pamlico to the Silver Bluff shoreline in South Carolina, for which other reconstructions suggest an expected relief of ~80m, illustrates the lack of match. Our results suggest that processes affecting either post-depositional changes in shoreline elevations or the creation of proxy sea-level estimates must be considered before using paleo sea-level position on continental margins. [ABSTRACT FROM AUTHOR]

We present a computational framework that allows investigating the Thermo-Hydro- Mechanical response of a representative part of a sedimentary basin during a glaciation cycle. We tackle the complexity of the problem, arising by the mutual interaction among several phenomena, by means of a multi-physics, multi-scale model with respect to both space and time. Our contribution addresses both the generation of the computational grid and the algorithm for the numerical solution of the problem. In particular we present a multi-scale approach accounting for the global deformation field of the lithosphere coupled with the Thermo-Hydro-Mechanical feedback of the ice load on a representative part of the domain at a finer scale. In the fine scale model we also include the erosion possibly caused by the ice melting. This methodology allows investigating the evolution of the sedimentary basin as a response to glaciation cycle at a fine scale, taking also into account the large spatial scale movement of the lithosphere due to isostasy. The numerical experiments are based on the analysis of simple scenario, and show the emergence of effects due to the multi-physics nature of the problem that are barely captured by simpler approaches. [ABSTRACT FROM AUTHOR]