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Despite the high detection level of the Italian seismic network and the risk associated with its fault networks, Central‐Southern Italy has no unique geophysical model of the crust able to illuminate its complex tectonics. Here, we obtain seismic attenuation and scattering tomography models of this area; both reveal high attenuation and scattering anomalies characterizing the entire Apenninic Chain and related to its East‐ and West‐dipping extensional Quaternary tectonic alignments. Fault‐associated fractured zones become preferential ways for circulating and degassing high‐attenuation CO2‐bearing fluids. A previously undetected fluid source area is a high‐attenuation volume below the Matese complex, while a similar smaller anomaly supports a fluid source near L'Aquila. The most prominent low attenuation and scattering volumes reveal a locked aseismic zone corresponding to the Fucino‐Morrone‐Porrara fault systems, representing a zone of significant seismic hazard. Plain Language Summary Geophysical methods are the most used tools for imaging the subsurface. Still, their resolution and reliability depend on the amount of good‐quality data and the sensitivity of the technique used for the target structures. Improvements in the seismic detection infrastructures of the last decade allow imaging zones characterized by sparse seismicity, like Central‐Southern Italy. Once combined with these data, new imaging techniques targeting attributes with higher sensitivity to stress and fluid saturation provide unprecedented resolution on tectonic interactions and fluid sources in this area. Here, we measured and mapped in 3D the energy lost by seismic waves during their propagation. Our results show a high‐attenuation volume elongated in the direction of the Apenninic Chain and particularly intense in Southern Italy, mapping fluid‐filled fracturing and a fluid source likely coinciding with the Matese area. The principal normal and reverse faults in the area control high‐attenuation zones. The most prominent low attenuation and scattering volume marked locked areas with low seismic energy release, suggesting them as the zones of stress accumulation. Key Points Scattering and attenuation tomography image the tectonics of the Apennine Mountain Belt Chain High‐attenuation anomalies mark crustal sources of CO2 following major structural alignments A high‐attenuation/high‐scattering volume reveals an extended fluid source beneath the Matese Mountains

The Quaternary strata on the Qinghai-Tibet Plateau contain rich information about the paleoclimate and environmental evolution, record the evolution process of the Quaternary regional tectonics, paleogeography, and geomorphology of the plateau, and are extremely important areas for studying the Quaternary geological events and regional environmental evolution. According to a comprehensive analysis of the regional stratigraphic data and the development and evolution characteristics of the biota, based on the differences in the lithostratigraphic units, sedimentary characteristics, landforms, and drainage systems, the Quaternary strata on the Qinghai-Tibet Plateau and its surrounding areas are divided into five stratigraphic regions: the Tarim region, Loess Plateau region, Qinghai-Tibet Plateau region, Yunnan-Guizhou Plateau region, and India-Ganges region. The Qinghai-Tibet Plateau stratigraphic region is divided into seven stratigraphic sub-regions: the West Kunlun-Karakorum, Altun-Qilian Mountains, Qaidam-Hehuang, East Kunlun-Bayan Har, Qiangtang, East Xizang-West Yunnan-West Sichuan, and Gangdise-Himalayan sub-regions. This paper briefly describes the lithostratigraphic units of the seven stratigraphic sub-regions of the Qinghai-Tibet Plateau. According to the lithostratigraphic sequence and its sedimentary characteristics, stratigraphic contact relationship, formation age, and evolution of the biota in each stratigraphic sub-region, the Quaternary tectonic paleogeographic evolution of the Qinghai-Tibet Plateau is divided into four stages. (1) The inherited differential uplift stage since the Pliocene (2.6−1.8/1.5 Ma): the regional sedimentary differences were significant, and the stratigraphic distribution was limited, the alluvial-proluvial sandy conglomerate was widely developed along the piedmont, and fluvial and lacustrine deposits were developed in the low-lying areas between the mountains. (2) The mountain range flattening stage (1.8/1.5−1.2/0.8 Ma): the erosion unconformity surfaces around the plateau were widely distributed, large rivers were formed, and lake sediments developed in the intermountain basins and the hinterland of the plateau. (3) 1.2/0.8−0.128 Ma: the plateau continued to rise in a large range, with significant topographic differences and intensified mountain erosion. At about 0.8 Ma, the plateau uplifted above the snow line and entered the cryosphere, mountain glaciers developed, and the alpine arid environment gradually formed. (4) 0.128 Ma-: the mountains rose and erosion intensified, and intermountain basins and lakes were widely distributed. There were significant differences in the regional sedimentary characteristics, and the sedimentary types developed toward diversification. The modern plateau landform pattern was basically formed.

We have selected 28 deep wells in the Southern Apennine area, most of which are located along and around the Val d’Agri Basin. The Southern Apennines, one of the most seismically active regions of the Italian peninsula, is a NE-verging fold-and-thrust belt characterised by the Meso–Cenozoic Apulia carbonate duplex system overlain by a thick column of Apennine carbonate platform and Lagonegro basin units. These units are unconformably covered by Neogene siliciclastic successions. Among the many Quaternary tectonic basins in the area, the Val d’Agri Basin is the most important intramontane depression, and is bordered by a ~ NW–SE-trending active fault system that represents one of the main seismogenic structures of the region. Moreover, the Val d’Agri Basin is the largest onshore oil field basin in Europe. In this context, we have analysed sonic log records from 28 deep wells and compared them with the corresponding stratigraphy and the other geophysical logs. We have obtained detailed measurements of the P-wave velocity (Vp) for each well from 0 to ~ 6 km depth, and found important lateral variations of Vp over very small distances. From these values, we have retrieved the densities of the main units crossed by the wells and the range of the overburden gradient in this area.

The geoconservation policies assumed by the Sicilian Region (Italy) induced to classify as geosites all the geodiversity preserved in the Sicilian natural reserves. In particular, two of these geosites present in the oriented natural reserve of the coastal lagoon of Cape Peloro (Messina, NE Sicily, Italy), denoted “Morpho–tectonic system of Cape Peloro–Lake Faro” and “Morpho–tectonic system of Cape Peloro–Lake Ganzirri”, were considered Global areal geosites on the base of their tectonic origin. Lacking an official scientific report of these sites, the present research was aimed to investigate the lagoon, in order to provide the (i) geological and structural framework, (ii) inventory, and (iii) quantitative assessment of geodiversity. The study geosites resulted to be originated during the post–Wurmian sea–level rise and the strong extensional tectonics affecting the Calabria–Peloritani Arc still active. Indeed, the lagoon depression hosting the Lakes Faro and Ganzirri, developed on low-relief coasts because of different systems of capable faults, NW–SE oriented in the Lake Faro and ENE–WSW oriented in the Lake Ganzirri. The quantitative assessment of geodiversity indicated high scores for the scientific value and the potential educational and touristic uses. On the basis of these results, it was possible to confirm the attribution of Lake Faro’s and Lake Ganzirri’s geodiversity to Global areal geosites, being the study morpho-structures key localities, providing indicators of representativeness, geological diversity, and rarity that ought to be protected as clear and unequivocal examples of the Earth’s geological history and evolution of the Quaternary tectonic coastal lagoons. Actual criticisms that could irreversibly affect the environmental equilibria have been evidenced. Possible actions for the redevelopment of the oriented natural reserve of the coastal lagoon of Cape Peloro and the extension of the geosites were also described.

Since about 20,000 years ago, the geography of the Earth has been profoundly modified by the gradual sea-level rise caused by the melting of continental ice sheets. Flat areas and regions characterized by very low gradients experienced, more than others, rapid flooding, with the progressive disappearance of vast coastal territories. Here we present a reconstruction of the late Quaternary coastline evolution of the north-western sector of the Sicilian Channel, constrained by high-resolution seismic profiles where the marker of the post-Last Glacial Maximum (LGM) marine transgression has been clearly identified and mapped. The locations of the post-LGM seismic horizon have been compared with predictions of a Glacial Isostatic Adjustment (GIA) model, which accounts for the migration of the shorelines in response to sea-level rise and for Earth's rotational and deformational effects associated with deglaciation. We have verified that most of the points mapped through seismic data interpretation fall along the palaeo-coastline that the GIA model predicts for the 21 kyrs B.P. time frame. However, the model shows a misfit in the marine sector between Mazara del Vallo and Sciacca, where the available data indicate a Quaternary tectonic uplift. The analysis of the seismic profiles provides useful constraints to current GIA models. These add on existing histories of relative sea level in the Mediterranean Sea, allowing to gain new insight into the evolution of the palaeo-geography of the region of study and of the whole Sicilian Channel since the LGM, even in areas where direct geophysical observations are not available yet. In this respect, one of the most attractive implications of the ancient coastline evolution is linked with the underwater archaeology. The sea-level rise heavily impacted the distribution of human settlements, possibly forcing site abandonment and migrations, and this is particularly relevant in the Mediterranean basin, the cradle of the western civilization. The underwater traces left by these ancient populations represent the fundamental proofs to reconstruct the early history of our precursors.

We can regard the occurrence of earthquakes as the partial release of tectonic stress by sudden brittle rupture. In the framework of linear elasticity, any indigenous source including earthquake rupture is represented by a moment tensor. The moment tensor is mathematically equivalent to the volume integral of stress release over the whole elastic region surrounding the source, and so we can quantitatively relate the centroid moment tensor (CMT) of seismic events with an unknown tectonic stress field. On the basis of such an idea and Bayesian statistical inference theory, we developed an inversion method to estimate the 3‐D pattern of tectonic stress from CMT data. Applying the CMT data inversion method to 12,500 seismic events in and around Japan, we obtained precise 3‐D tectonic stress patterns that illuminate the present‐day (Quaternary) complex tectonic motion of Japanese islands. The stress pattern of the Kuril‐Japan‐Nankai arc is basically E–W compression, but the direction of intermediate principal stress changes from N–S (reverse faulting type) in northeast Japan to vertical (strike‐slip faulting type) in southwest Japan. On the other hand, the stress pattern of the Ryukyu and Izu‐Bonin back‐arc regions is basically trench perpendicular tension (normal faulting type). In addition to these basic stress patterns governed by mechanical interaction between the Eurasian, North American, Pacific, and Philippine Sea plates, we can recognize several characteristic local stress patterns corresponding to the horizontal motion of the Kuril fore‐arc sliver, the collision of the Izu Peninsula with the mainland of Japan, and the opening of the Beppu‐Shimabara rift zone.

The Datça graben in southwestern Anatolia is a WNW-trending seismically active depression, with tectonic activity since Pliocene time. This tectonic activity is controlled by normal faults, which have effected ancient settlements. The Cnidus city (old and modern) –an ancient mercantile centre during the Hellenistic, Roman and Byzantine periods– is one of the places that has recorded this activity. The ancient harbour walls of Cnidus, lying 2.2-4.0m below sea level, contain important traces about sea-level changes and tectonics over the past 2.6kyr. Palaeostress analysis along boundary faults in the Datça graben yields an almost N–S oriented pure tensional regime, compatible with earthquake focal mechanism solutions located around the Datça Peninsula. Additionally, an almost E−W trending surface rupture related to a historical earthquake in modern Cnidus, which shows normal fault characteristics, gives further support to the ongoing extension along the Kızlan, Karaköy and Cnidus fault zones. Previous studies on late Quaternary sea-level changes around the Datça Peninsula suggest that 2.6kyr ago sea level was 1.0-1.25m lower than today. From the present-day depth of the Old Cnidus harbour remains and regional sea-level records, it can be inferred that tectonics has played a significant role. Our calculations show that the Datça graben is subsiding at rates of 0.36-0.46mm/yr in the central part and 1.05-1.15mm/yr in the southern part. These values match those found in other areas around the Datça Peninsula.

Late Quaternary tectonic deformation of coastal areas is usually examined based on the height distribution of paleo-shorelines observed on marine terraces. However, it is difficult to examine deformation along the subduction zone, in which small, isolated islands are distributed. In this paper, the author focuses on the widespread shallow submarine terraces surrounding the Iheya–Izena islands in the middle part of the Nanseishoto Islands, Southwest Japan, where crustal deformation is not known. The islands are located in the intermediate zone between island shelf uplifted during the Late Quaternary and the rift zone occurred to the northwest, along the Okinawa trough. Detailed topographic anaglyph images and maps of the islands were produced using a digital elevation model (DEM) of the seafloor, which is stored by the Japan Coast Guard (JCG) and the Advanced Institute of Science and Technology (AIST). Topographic anaglyph images enabled us to identify the widespread distribution and deformation of the shallow seafloor above − 200 m using red–cyan glasses. Four terrace-like features divided by small steps were found on the shallow seafloor, which are named T1, T2, T3, and T4, in descending order. Topographic expressions of paleo-shoreline depths are preserved on submarine terraces formed during the last glacial period. The paleo-shoreline depths of terraces T2 and T3 are − 60 m and − 70 m on the west side and − 70 m and − 80 m, respectively, on the east side of Iheyajima Island; this indicates southeastward tilting. The tilting ratio of T2 and T3 was calculated to approximately 1‰. The tilting rate is approximately 1 × 10–4/kyr, assuming that the T2 was formed in 10–11 kyr. This is much more rapid than that of the last inter-glacial marine terraces in the Muroto peninsula of Shikoku, Japan, with a tilting rate of 4 × 10–5/kyr, which formed by steep northward tilting against the Nankai subduction zone. The author suggests that this phenomenon is not related to mega-thrusting along the subduction zone, but rather to local deformation, probably caused by the reverse faulting of nearby active submarine faults along the west side of the islands.

In this review we compile and document the elevation, indicative meaning, and chronology of marine isotope substage 5a and 5c sea level indicators for 39 sites within three geographic regions: the North American Pacific coast, the North American Atlantic coast and the Caribbean, and the remaining globe. These relative sea level indicators, comprised of geomorphic indicators such as marine and coral reef terraces, eolianites, and sedimentary marine- and terrestrial-limiting facies, facilitate future investigation into marine isotope substage 5a and 5c interstadial paleo-sea level reconstruction, glacial isostatic adjustment, and Quaternary tectonic deformation. The open-access database, presented in the format of the World Atlas of Last Interglacial Shorelines (WALIS) database, can be found at https://doi.org/10.5281/zenodo.5021306 (Thompson and Creveling, 2021).

Exploring the 'fragile crust of our planet' is crucial for human survival holding an immense social and economic significance. Therefore, innovative approaches become of utmost importance for obtaining precise subsoil models in urban areas making the latter more resilient to natural disasters. Due to logistic issues and a high level of anthropogenic disturbance and related background noise, urban areas are usually intrinsically more problematic for applying geophysical prospecting methods. This work presents the results obtained by Deep Electrical Resistivity Tomography and P wave Seismic Reflection surveys performed along the Ferrara, north Italy, city walls documenting the adaptability of the geophysical surveys and how it is possible to obtain high-quality electrical resistivity and seismic data even in complex urban settings. The joint interpretation of geoelectrical and seismic data fully integrated with tectonic, geological and hydrogeological information allowed to reconstruct the stratigraphic evolution down to a depth of about 1.5 km. These results highlight the occurrence of a syndepositional Quaternary tectonic tilting associated with the growth of a fault-propagation fold.