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In Antarctica, the severe climatic conditions and the thick ice sheet that covers the largest and most internal part of the continent make it particularly difficult to systematically carry out geophysical and geodetic observations on a continental scale. It prevents the comprehensive understanding of both the onshore and offshore geology as well as the relationship between the inner part of East Antarctica (EA) and the coastal sector of Victoria Land (VL). With the aim to reduce this gap, in this paper multiple geophysical dataset collected since the 1980s in Antarctica by Programma Nazionale di Ricerche in Antartide (PNRA) were integrated with geodetic observations. In particu-lar, the analyzed data includes: (i) Geodetic time series from Trans Antarctic Mountains DEFormation (TAMDEF), and Victoria Land Network for DEFormation control (VLNDEF) GNSS stations installed in Victoria Land; (ii) the integration of on-shore (ground points data and airborne) gravity measurements in Victoria Land and marine gravity surveys performed in the Ross Sea and the nar-row strip of Southern Ocean facing the coasts of northern Victoria Land. Gravity data modelling has improved the knowledge of the Moho depth of VL and surrounding the offshore areas. By the integration of geodetic and gravitational (or gravity) potential results it was possible to better con-strain/identify four geodynamic blocks characterized by homogeneous geophysical signature: the Southern Ocean to the N, the Ross Sea to the E, the Wilkes Basin to the W, and VL in between. The last block is characterized by a small but significant clockwise rotation relative to East Antarctica. The presence of a N-S to NNW-SSE 1-km step in the Moho in correspondence of the Rennick Geo-dynamic Belt confirms the existence of this crustal scale discontinuity, possibly representing the tectonic boundary between East Antarctica and the northern part of VL block, as previously pro-posed by some geological studies.

In Antarctica, the severe climatic conditions and the thick ice sheet that covers the largest and most internal part of the continent make it particularly difficult to systematically carry out geophysical and geodetic observations on a continental scale. It prevents the comprehensive understanding of both the onshore and offshore geology as well as the relationship between the inner part of East Antarctica (EA) and the coastal sector of Victoria Land (VL). With the aim to reduce this gap, in this paper multiple geophysical dataset collected since the 1980s in Antarctica by Programma Nazionale di Ricerche in Antartide (PNRA) were integrated with geodetic observations. In particular, the analyzed data includes: (i) Geodetic time series from Trans Antarctic Mountains DEFormation (TAMDEF), and Victoria Land Network for DEFormation control (VLNDEF) GNSS stations installed in Victoria Land; (ii) the integration of on-shore (ground points data and airborne) gravity measurements in Victoria Land and marine gravity surveys performed in the Ross Sea and the narrow strip of Southern Ocean facing the coasts of northern Victoria Land. Gravity data modelling has improved the knowledge of the Moho depth of VL and surrounding the offshore areas. By the integration of geodetic and gravitational (or gravity) potential results it was possible to better constrain/identify four geodynamic blocks characterized by homogeneous geophysical signature: the Southern Ocean to the N, the Ross Sea to the E, the Wilkes Basin to the W, and VL in between. The last block is characterized by a small but significant clockwise rotation relative to East Antarctica. The presence of a N-S to NNW-SSE 1-km step in the Moho in correspondence of the Rennick Geodynamic Belt confirms the existence of this crustal scale discontinuity, possibly representing the tectonic boundary between East Antarctica and the northern part of VL block, as previously proposed by some geological studies.

Crustal deformation analysis in seismogenic areas is one of the most important applications of GNSS. In the last twenty years, the GNSS technology has opened new perspectives in this field allowing the estimation of the crustal deformation at different scales both in time and in space. Tectonic deformations can be reliably estimated either at regional and fault scale. This allows the analysis of the different phases of the seismic cycle. Particularly, co-seismic and post-seismic deformations can be properly evaluated. Also, recent studies aim at studying the inter-seismic phase giving important insights in the dynamic of the crust in seismic prone areas. These studies are commonly based on the analysis of time series from GNSS permanent stations. In this paper, a method for filtering these data is presented and a case study based on the FReDNet data is illustrated.

The study of crustal deformation fields caused by earthquakes is important for a better understanding of seismic hazard and growth of geological structures in tectonically active areas. In this study, we present, using interferometric measurements constructed from Sentinel-1 Terrain Observation with Progressive Scan (TOPS) data and ALOS-2 ScanSAR, coseismic deformation and source model of the Mw 7.3, 12 November 2017 earthquake that hit northwest of the Zagros Mountains in the region between Iran–Iraq border. This was one of the strongest seismic events to hit this region in the past century, and it resulted in an uplift area of about 3500 km2 between the High Zagros Fault (HZF) and Mountain Front Fault (MFF) with a maximum amount of 70 cm south of Miringe fault. A subsidence over an area of 1200 km2 with a maximum amount of 35 cm occurred near Vanisar village at the hanging wall of the HZF. Bayesian inversion of interferometric synthetic aperture radar (InSAR) observations suggests a source model at a depth between 14 and 20 km that is consistent with the existence of a decoupling horizon southwest edge of the northern portion of the Zagros Mountains near the MFF. Moreover, we present evidence for a number of coseismically induced rockslides and landslides, the majority of them which occurred along or close to pre-existing faults, causing decorrelation in differential interferograms. Exploiting the offset-tracking technique, we estimated surface motion by up to 34 and 10 m in horizontal and vertical directions, respectively, due to lateral spreading on a big coseismic-induced landslide near Mela-Kabod. Field observations also revealed several zones of en echelon fractures and crack zones developed along a pre-existing fault passing through Qasr-e Shirin City, which exhibited secondary surface slip by up to 14 cm along its strike.

In order to make inferences on the geodynamics of Antarctica, geodetic and gravimetric maps derived from past and new observations can be used. This paper provides new insights into the geodynamics of Antarctica by integrating data at regional and continental scales. In particular, signatures of geodynamic activity at a regional extent have been investigated in Victoria Land (VL, Antarctica) by means of Global Navigation Satellite System (GNSS) permanent station observations, data from the VLNDEF (Victoria Land Network for Deformation control) discontinuous network, and gravity station measurements. At the continental scale, episodic GNSS observations on VLNDEF sites collected for 20 years, together with continuous data from the International GNSS Service (IGS) and Polar Earth Observing Network (POLENET) sites, were processed, and the Euler pole position assessed with the angular velocity of the Antarctic plate. Both the Bouguer and the free-air gravity anomaly maps were obtained by integrating the available open-access geophysics dataset, and a compilation of 180 gravity measurements collected in the VL within the Italian National Program for Antarctic Research (PNRA) activities. As a result, new evidence has been detected at regional and continental scale. The main absolute motion of VL is towards SE (Ve 9.9 &plusmn, 0.26 mm/yr, Vn &minus, 11.9 &plusmn, 0.27 mm/yr) with a pattern similar to the transforms of the Tasman and Balleny fracture zones produced as consequence of Southern Ocean spreading. Residual velocities of the GNSS stations located in VL confirm the active role of the two main tectonic lineaments of the region, the Rennick&ndash, Aviator and the Lillie&ndash, Tucker faults with right-lateral sense of shear. The resulting VL gravity anomalies show a NW region characterized by small sized Bouguer anomaly with high uplift rates associated and a SE region with low values of Bouguer anomaly and general subsidence phenomena. The East and West Antarctica are characterized by a different thickness of the Earth&rsquo, s crust, and the relative velocities obtained by the observed GNSS data confirm that movements between the two regions are negligible. In East Antarctica, the roots of the main subglacial highlands, Gamburtsev Mts and Dronning Maud Land, are present. The Northern Victoria Land (NVL) is characterized by more scattered anomalies. These confirm the differences between the Glacial Isostatic Adjustment (GIA) modeled and observed uplift rates that could be related to deep-seated, regional scale structures.

Central Italy is affected by intense crustal deformation processes due to active tectonics driven by the relative motions between the African and the Eurasia plates. In this area extensional tectonics is responsible for strain values of 1.5-2 cm/year ( Carafa and Bird, 2016 and references therein) and for intense CO2 gaseous emissions. Free CO2 emissions and groundwaters affected by CO2 discharges introduce in the atmosphere of central Italy over 20 Mt/year of CO2, about 1/3 of the total geological CO2 degassed in Italy (e.g.Chiodini et al., 2013). Fluctuations of the stress field could be, in principle, revealed by GPS or by InSAR techniques but technological constraint factors may often limit these researches. Further monitoring techniques which include geochemical and hydrogeologic parameters revealed intense concentration fluctuations in past ten years (Pierotti et al., 2017). Satellite techniques able to detect thermal anomalies due to possible geochemical variations of the atmospheric composition induced by degassing phenomena have been utilized (e.g.Tramutoli et al., 2013). About in the same periods variations in various parameters evidenced possible crustal deformative processes. Part of the observed signals have been detected before mainshocks and could be related to aseismic slip (e.g. Johnston and Linde (2002) or to seismic slip eventually induced by fluctuations in minor seismicity. Crustal rheological characteristics linked to shallow depth of earthquakes and to intense circulation of deep originated geofluids could have allowed the recording of described parameters (Martinelli and Dadomo, 2017). Earthquake forecasting researches could benefit by the joint utilization of different monitoring techniques applied to geofluids.

The western Aegean region of Turkey is highly populated; the centrally-located city of Izmir is the third largest city in Turkey. This region has suffered very large earthquakes in the past, of which one of the most devastating occurred in 1928. Some areas are particularly prone to severe ground liquefaction. This study is concerned with the earthquake potential of the region, focusing on a possible earthquake faulting mechanism and its associated characteristics based on historical and current regional seismicity, tectonics, crustal deformation and geo-archaeological evidence. The first part of the study presents a faulting mechanism, tectonics, recurrences and the fundamental characteristics of existing faults and past earthquakes. Then, the characteristics of potential earthquakes are discussed in light of evaluations of recent crustal deformation and empirical relations developed for Turkey by the first author. The final part presents geotechnical aspects, including liquefaction and the characteristics of strong ground motions recorded in the region, such as spectral acceleration, attenuation of maximum ground acceleration and velocity. Furthermore, their possible implications are discussed in view of current Turkish seismic design codes. The faulting mechanism of regional earthquakes has indicated that the classical horst-graben concept does not explain the earthquake mechanism in the region of concern. The magnitude of earthquakes inferred from the length and type of known active faults may be up to 7.7. Based on an evaluation of crustal deformation in the region, the highest disturbing stress and mean stress concentration with a compressive character occurs in close proximity to İzmir. The spectral accelerations generally exceed those of Turkish seismic design codes. The liquefaction potential in areas of alluvial quaternary deposits is particularly high and is one of the major geotechnical issues in light of historical records and evaluations presented in this manuscript. © 2014, Springer-Verlag Berlin Heidelberg.

Strain data recorded by two laser interferometer–strainmeters operating in the Baksan (Russia) and Gran Sasso (Italy) underground observatories, and the length-of-day (LOD) data describing the variable rate of the Earth's rotation are used to study the relation between the deformation processes in the lithosphere and the global geodynamics of the Earth over short time intervals. The methods applied are based on analysis of the coherence of the studied processes, and correlation analysis. A significant (90%) correlation is revealed between the local deformation fields at two remote observation stations, which proves the existence of a global (at least on the scale of the Eurasian plate) component in the Earth's deformation field that manifests itself at characteristic time intervals of up to 1–2 months. At the same level of significance, the correlation between the local deformation fields and variations in the rate of the Earth's rotation has also been identified. The found correlations in the tidal low-frequency range are caused by the direct impact of the long-period tidal loading ( M f and M tm waves) on the lithosphere and the length-of-the-day (LOD). On the contrary, the significant correlation in the non-tidal range is probably linked to irregular perturbations of the continental character, which create a coherent interference in the studied processes. The global mechanism that causes this coherent noise requires further study.

The two events of Mw 6.11 and 5.96 [EMERGEO Working Group 2012, this volume] that took place on May 20 and 29, 2012, respectively, in the Po Plain, and the associated seismic sequence, represent the response of the brittle upper crust (hypocentral depth ca. 10 km) to the compressive stress in the outer Apennine Arc. Kinematically, the motion of the Apennines that has led to a compressional regime in the Po Plain can be represented as a counterclockwise rotation, as demonstrated by the shortening of the transalpine baselines, with a rate that decreases going west [Caporali and Martin 2000]. The compressive stress field is known from borehole breakout data [Pierdominici and Heidbach 2012] and it agrees with the principal directions of the strain rate derived from global positioning system (GPS) data. The geodetic strain rate for seismic zone 912 (Dorsale Ferrarese, according to Meletti et al. [2008]) is 92.86 ±0.04 nstrain/yr, which is a relatively high value [Caporali et al. 2011]. On a more local scale, the Mirandola fault is described in the Database of Individual Seismic Sources (DISS; http://diss.rm.ingv.it/) under the ID ITIS107 as a possible individual source, and it has a position, strike, dip, size and expected maximum magnitude [Burrato et al. 2003, Carminati et al. 2010, Scrocca et al. 2007] that are very close to the main events of the 2012 sequence. Several permanent GPS stations were in activity in the area. Using ultrarapid international Global Navigation Satellite Systems (GNSS) Service (IGS) orbits and the Bernese BSW 5.0 software [Dach et al. 2007] at our computing facility, a fast solution for the coseismic displacement was published on the May 21, 2012, and on the May 30, 2012, for the events of May 20 and 29, 2012, respectively. The largest signal was about 2 cm in the North direction at the station SGIP (San Giovanni in Persiceto), which was relatively consistent with the fault-plane solution [Devoti 2012, this volume]. In this study, we present more detailed estimates of the coseismic offsets at several other stations in the area, including a kinematic solution at 30 s temporal resolution. The coseismic displacements are inverted using the Okada [1985] model and a preliminary model of the two faults is obtained for each of the two main events, taking into account the available synthetic aperture radar (SAR) data. […]

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2011, Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2011, Bu çalışmada Türkiye nin Deprem Riski Yüksek Jeo-Stratejik ancak tektonik rejimleri farklı Bölgelerinde Deprem Davranışının Çok Disiplinli Yaklaşımlarla Araştırılması (TÜRDEP) Projesi kapsamında elde edilen tilt verileri kullanılarak uzun ve kısa dönem yer kabuğu deformasyonlarının analizine yönelik bir yaklaşım oluşturulmuştur. Ülkemizde halihazırda çalışılmamış bu konuda, çalışma alanı olarak doğrultu atımlı fay sistemleri üzerinde yer alan iki ayrı pilot bölge seçilmiştir. Bu bölgeler sırasıyla Kuzey Anadolu Fay (KAF) Sistemi’nin güney kolu üzerinde yer alan Gönen Pilot Bölgesi ve Doğu Anadolu Fay (DAF) Sistemi üzerinde yer alan Kahramanmaraş-Türkoğlu Pilot Bölgesi’dir. Yaklaşık olarak 4 yıllık tilt verileri analiz edilmiş, aynı zaman aralığına denk düşen sıcaklık, basınç, günlük toplam yağış ve depremlerle ilişkileri irdelenmiştir. Bölgesel meteorolojik, hidrolojik, tektonik değişimler tanımlanmış, deprem öncesi, deprem anı ve deprem sonrası dönemlere ait tilt anomalileri belirlenmiş ve yorumlanmıştır., By the approach introduced in this study, the short and long term crustal deformations were analyzed using tilt data which was obtained within the framework of the “Multi-Disciplinary Earthquake Researches in high risk regions of Turkey” (TURDEP) project, carried out at Earth and Marine Sciences Institute of TUBITAK’s Marmara Research Center. Two separate pilot areas were determined on strike-slip fault zone as study area on this subject, which has not yet been studied in our country. These areas are namely the Gönen pilot area on the southern branch of the Northern Anatolian Fault (NAF) Zone and the Kahramanmaraş-Türkoğlu pilot area on the Eastern Anatolian Fault Zone. The tilt data corresponding to an approximate period of 4 years is analyzed with respect to its correlation with other data within the same time frame such as temperature, pressure, total daily precipitation and earthquake occurrences. Regional meteorological, hydrological and tectonic variations and tilt anomalies for the pre- co- and post-seismic periods were determined and interpreted., Yüksek Lisans, M.Sc.

The investigation in the present thesis is focused on the South Balkan extensional region using Global Positioning System (GPS) technique. The GPS-derived velocity field from 225 episodic and continuous GPS stations covering the territory of Central and East Mediterranean for the period 1996-2009 has been analysed and discussed in the context of present-day tectonics block models. The geodynamic processes in the region of Southwest Bulgaria (SWB) and Northern Greece (NG) are investigated by GPS measurements acquired during a 12-year (1996-2008) period. SWB and NG are recent active tectonic and seismotectonic regions. The SWB is the most active seismic region of the Bulgarian territory - in the Krupnik – Kresna region one of the most catastrophic earthquakes in continental Europe during the last two centuries occurred in 1904. NG is an area with widespread seismic activity ranging from low to high with destructive earthquakes of M≥6.0 from historical to recent times. The obtained velocity field of the Earth's crust is represented by 34 points in SWB and 21 points in NG encompassing the region. The results show southward displacements between 2-10 mm/yr. The strain rates for the region obtained by GPS measurement for the region are presented and discussed together with seismological events. By comparision to the geological and seismotectonic data, the results obtained from the GPS observations confirm the present-day activity of the fault structures and the dominating extension to the north-south. This extension is in agreement with the regional tectonic model of the East Mediterranean. The current tectonics of Albania is documented by neotectonics indices and by a large number of medium size earthquakes. The focal mechanisms suggest the existence of current shortening across the external Albanides whereas the internal Albanides are affected by E-W to N-S extension. To investigate the kinematics of the Albanides, we integrate continuous and episodic GPS measurements with focal mechanisms from the Regional Centroid Moment Tensor catalogue. This study has allowed distinguishing a western Albania affected by westward motions relative to the Apulia microplate, illustrating the ongoing collision of external Albanides, whereas inner Albanides present southward motion relative to both Apulia and stable Eurasia. The Skutar-Pesh Fault Zone, between Dinarides and Albanides, is identified as the possible northern limit of an area including Albania and western Greece, affected by a clockwise rotation relative to Apulia and also the northern limit of the Balkans (inner Albanides, Macedonia, Bulgaria) affected by southward motion relative to Apulia and stable Eurasia. The other transverse fault zone of the Albanides, the Diber-Elbasani fault, appears to be affected mainly by a moderate extension. Compilation of the published GPS data with our data set allows to identify the external-inner Albanides limit as the western border of the domain (inner Albania, northern Greece, Macedonia, Bulgaria) affected by southward displacements relative to stable Eurasia, whereas Skutar-Pesh fault probably forms also its northern limit. The analysis of the velocity field for the whole studied area leads to the hypothesis of a continuous deformation to the detriment of local deformation at the borders of stable blocks., Dans cette thèse, nous présentons une quantification de la déformation en cours du sud des Balkans et de la Méditerrnée centrale et orientale par GPS. Le champs de vitesses a été déduit de l'analyse de données issues de 225 stations GPS permanentes ou épisodiques pour la période 1996-2009. Ce champs de vitesse est analysé et discuté pour essayer de déterminer si le champ de vitesse est continu ou si, au contraire, des blocs stables peuvent être individualisés. La déformation actuelle du sud-ouest de la Bulgarie et du nord de la Grèce ont été particulièrement étudiés à partir de mesures réalisées de 1996 à 2008. Cette région est particulièrement active comme le montre la sismicité historique et en particulier le séisme de Krupnik en 1904 (sud-ouest de la Bulgarie) qui fut un séisme parmi les plus destructeur en Europe continentale au cours des deux derniers siècles. Le nord de la Grèce est quant à lui caractérisé par des séismes destructeurs de M > 6. Les résultats obtenus montrent l'existence de déplacements vers le sud par rapport à l'Eurasie stable s'accroissant du Nord (2mm/an) vers le sud de la région étudiée (10 mm/an). Les tenseurs de taux de déformation sont présentés et discutés à la lumière de la déformation exprimée lors des séismes. Ces deux types d'information montrent tous deux une prédominance d'une extension Nord-sud en accord avec les données géologiques (présence de grabens Est-Ouest) et les modèle proposés pour la Méditerranée centrale et orientale. A l'ouest des Balkans, la déformation actuelle de l'Albanie s'exprime par des nombreux indices néotectoniques et une sismicité importante présentant de nombreux séismes historiques destructeurs. Données géologiques et sismotectoniques montrent d'une part l'existence d'un raccourcissement dans les Albanides externes et d'autre part une extension Est-Ouest et Nord –Sud dans les Albanides externes. Les vitesses de déplacements ont été quantifiées par GPS continu et épisodiques à partir de 2003. Ces vitesses ainsi que les mécanismes au foyer montrent un raccourcissement en cours à travers l'Adriatique (déplacements des Albanides externes vers l'ouest par rapport à la plaque Apulie), et un déplacement vers le sud des Albanides internes à la fois par rapport à la plaque Apulie et à la plaque Eurasie. La zone de failles Skutar-Pesh entre Albanides et Dinarides semble former la limite nord de la zone affectée par un déplacement vers le sud par rapport à l'Eurasie comprenant l'est de l'Albanie, la Macédoine, la Bulgarie et la Grèce. Les Albanides externes semblent être segmentées par des failles transverses actives (faille de Lezhë et de l'ile d'Othoni et du col de Dhërmi) associées à une importante sismicité historiques. Les Albanides internes sont affectées à la fois par une extension Nord-sud le long de la faille d'Elbasani-Diber, du graben de Korca et par une extension est-ouest de part et d'autre du graben d'Ohrid. Le domaine affecté par un déplacement vers le sud est donc limité à l'ouest par la transition antre les Albanides externes et les Albanides Internes et au nordouest par la faille de Skutar-Pesh qui se poursuit en Macédoine. Sur l'ensemble du domaine étudié, notre analyse du champ de vitesse nous conduit à privilégié l'hypothèse d'une déformation continue au détriment d'une déformation localisée aux frontières de blocs stables.

We describe the procedures used to combine into a uniform velocity solution the observations of more than 80 continuous GPS stations operating in the central Mediterranean in the 1998-2004 time interval. We used a dis- tributed processing approach, which makes efficient use of computer resources, while producing velocity esti- mates for all stations in one common reference frame, allowing for an effective merging of all observations in- to a self-consistent network solution. We describe the CGPS data archiving and processing procedures, and pro- vide the main results in terms of position time-series and velocities for all stations observed for more than three years. We computed horizontal and vertical velocities accounting for the seasonal (annual and semi-annual) sig- nals, and considering the off-sets in the coordinate time-series caused by station equipment changes. Weighted post-fit RMS of the north, east and vertical velocity components are in the range of 1.57-2.08 mm, 1.31-3.28 mm, and 3.60-7.24 mm, respectively, which are reduced by solving for seasonal signals in the velocity estimates. The annual and semi-annual signals in the height components, with amplitudes up to 4.8 mm, are much stronger than those in the horizontal components. The mean amplitudes of annual and semi-annual signals are within 0.18-0.47 mm, 0.23-0.52 mm and 0.55-1.92 mm in the north, east and vertical components, respectively.

Geodetic and seismic evidence of crustal deformations in the Ionian area are shown in this paper. The Ionian GPS network, composed of nine sites crossing the Ionian Sea from Calabria, Southern Italy, to Northwestern Greece, was established and surveyed in 1991, 1994, 1995 within the framework of the TYRGEONET project (Anzidei et al., 1996). In 1996 a return campaign was carried out after the occurrence of seismic activity in 1995. The displacement pattern obtained for the Greek side of the network agrees well with those previously displayed, both in magnitude and direction, confirming a mean displacement rate of about 1-2 cm1/yr. The same agreement is not found for the Italian side of the network, where no significant deformations were detected between 1994 and 1996. Seismic deformation was also studied for the same area, starting from the moment tensors of events which occurred in the last 20 years with magnitude greater than 5.0; evident similarity with the displacement field exhibited by the Greek side of the Ionian Sea by geodetic surveys was inferred. On the contrary, the motion detected for the Italian area cannot be simply related to seismic activity.