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We present a research project intended to investigate the structure of Cumbre Vieja volcano in La Palma, Canary Islands, after the September-December 2021 Tajogaite eruption. Starting in the summer of 2023, we will deploy a dense network of 35 broadband seismometers provided by GFZ and University of Granada, that will add up to the ~20 permanent stations already in operation by the Spanish National Geographic Institute (IGN) and the Volcanological Institute of Canary Islands (INVOLCAN). In this way, we expect to obtain a dense coverage of the whole island with inter-station distances of about 5 km. This broadband network will be in operation for a period of about a year. Additionally, we will perform a series of large-N experiments using 200 geophones (provided by GFZ). First we will deploy these instruments along linear profiles across the island, in N-S and E-W directions. In a second stage, we will move the geophones to a bidimensional grid configuration centered at the eruption site. We estimate that inter-station distances will be of ~0.5 km in both cases, and the recording periods will span around 4-5 months per configuration. The data obtained from these deployments will be used to perform a dense receiver function analysis and ambient noise tomography to improve the knowledge of the shallow velocity structure of the volcanic rift around the eruption area down to a depth of a few km and to image the magma sources in the crust and uppermost mantle., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

In this study, 3-D models of P-wave velocity (Vp) and P- and S-wave ratio (Vp/Vs) of the crust and upper mantle in the Eastern and eastern Southern Alps (northern Italy and southern Austria) were calculated using local earthquake tomography (LET). The dataset includes high-quality arrival-times from well-constrained hypocenters observed by the dense, temporary seismic networks of the AlpArray AASN and SWATH-D. The resolution of the LET was checked by synthetic tests and analysis of the Model Resolution Matrix. The small inter-station spacing (average of ∼15 km within the SWATH-D network) allowed us to image crustal structure at unprecedented resolution across a key part of the Alps. The derived P velocity model revealed a highly heterogeneous crustal structure in the target area. One of the main findings is that the lower crust is thickened, forming a bulge at 30-50 km depth just south of and beneath the Periadriatic Fault and the Tauern Window. This indicates that the lower crust decoupled both from its mantle substratum as well as from its upper crust. The Moho, taken to be the iso-velocity contour of Vp=7.25 km/s, agrees with the Moho depth from previous studies in the European and Adriatic forelands. It is shallower on the Adriatic side than on the European side. This is interpreted to indicate that the European Plate subducted beneath the Adriatic Plate in the Eastern and eastern Southern Alps.

Objective: Antibodies to citrullinated and homocitrullinated (also known as carbamylated) proteins, specific for rheumatoid arthritis (RA), are associated with cardiovascular disease (CVD). Immune complexes containing these proteins have been identified in the atherosclerotic plaque of CVD patients. In mice, homocitrullinated low-density lipoprotein (HomoCitLDL) promotes foam cell formation, which is critical in the pathogenesis of atherosclerosis. We aimed to investigate the atherogenic potential of HomoCitLDL and citrullinated low-density lipoprotein (CitLDL) in RA. Method: Human LDL was homocitrullinated in potassium cyanate and citrullinated by rabbit skeletal muscle peptidyl arginine deiminase-2. The modifications were confirmed by mass spectrometry. Primary human monoctyes from healthy subjects (N = 8) were differentiated to macrophages using macrophage colony-stimulating factor and incubated with modified LDL. Foam cells were visualized using Oil Red O staining. Serum from RA patients (N = 101) and controls (N = 32) was tested for immunoglobulin G antibodies to modified LDL using enzyme-linked immunosorbent assay. Results: HomoCitLDL and CitLDL strongly induced foam cell production (> 90%) versus unmodified LDL (11%) (p Conclusions: HomoCitLDL and CitLDL have atherogenic properties in vitro. Antibody responses to HomoCitLDL, but not CitLDL, were detected in RA patients.

This dataset contains a high resolution Moho map of the in the Eastern Alps focused on the SWATH-D network. The Moho map was produced by manually picking the Moho on narrow transects (CCP stacks) calculated with the receiver function method. These manual picks were then fit with a spline in 3-D. Three separate and sometimes overlapping maps are included corresponding to the European, Adriatic, and Pannonian Mohos. In addition to Moho depth, Ps travel time and crustal average Vp/Vs are also reported.

The Anillo is a dense temporary seismic and geodetic network extending approximately 200 km along the strike of the subduction zone in North Chile in order to investigate how earthquakes and aseismic slip scale over a broader spectrum of source sizes, to understand the complex relationships between seismic and aseismic deformation, and to identify possible structural controls. This experiment is embedded into a larger scale experimental effort carried out by institutions in Germany and Chile. Waveform data are available from the GEOFON data centre, under network code Y6.

The AlpArray experiment and the deployment of Swath-D together with the dense permanent network in Italy allow for detailed imaging of the spatio-temporal imaging complexity of seismic wave-fields within the greater Alpine region. The distance of any point within the area to the nearest station is less than 30 km, resulting in an average inter-station distance of about 45 km. With a much denser deployment in a smaller region of the Alps (320 km in length and 140 km wide), the Swath-D network possesses an average inter-station distance of about 15 km. We show that seismogram sections with a spatial sampling of less than 5 km can be obtained using recordings of these regional arrays for just a single event. Multiply reflected body waves can be observed for up to 2 h after source time. In addition, we provide and describe animations of long-period seismic wave-fields using recordings of about 1300-1600 broadband stations for six representative earthquakes. These illustrate the considerable spatio-temporal variability of the wave-field's properties at a high lateral resolution. Within denser station distributions like those provided by Swath-D, even shorter period body and surface wave features can be recovered. The decrease of the horizontal wavelength from P to S to surface waves, deviations from spherically symmetric wavefronts, and the capability to detect multi-orbit arrivals are demonstrated qualitatively by the presented wave-field animations, which are a valuable tool for educational, quality control, and research purposes. We note that the information content of the acquired datasets can only be adequately explored by application of appropriate quantitative methods accounting for the considerable complexity of the seismic wave-fields as revealed by the now available station configuration., International Journal of Earth Sciences, 111 (1), ISSN:1437-3254, ISSN:1437-3262

Coda-Q is used to estimate the attenuation and scattering properties of the Earth. So far focus has been on earthquake data at frequencies above 1 Hz, as the high noise level in the first and second microseismic peak, and possibly lower scattering coefficient, hinder stable measurements at lower frequencies. In this work, we measure and map coda-Q in the period bands 2.5-5 s, 5-10 s and 10-20 s in the greater Alpine region using noise cross-correlations between station pairs, based on data from permanent seismic stations and from the temporary AlpArray experiment. The observed coda-Q for short interstation distances is independent of azimuth so there is no indication of influence of the directivity of the incoming noise field on our measurements. In the 2.5-5 s and 5-10 s period bands, our measurements are self-consistent, and we observe stable geographic patterns of low and high coda-Q in the period bands 2.5-5 s and 5-10 s. In the period band 10-20 s, the dispersion of our measurements increases and geographic patterns become speculative. The coda-Q maps show that major features are observed with high resolution, with a very good geographical resolution of for example low coda-Q in the Po Plain. There is a sharp contrast between the Po Plain and the Alps and Apennines where coda-Q is high, with the exception a small area in the Swiss Alps which may be contaminated by the low coda-Q of the Po Plain. The coda of the correlations is too short to make independent measurements at different times within the coda, so we cannot distinguish between intrinsic and scattering Q. Measurements on more severely selected data sets and longer time-series result in identical geographical patterns but lower numerical values. Therefore, high coda-Q values may be overestimated, but the geographic distribution between high and low coda-Q areas is respected. Our results demonstrate that noise correlations are a promising tool for extending coda-Q measurements to frequencies lower than those analysed with earthquake data.

The Bransfield Strait is a seismically active extensional rift located between the Antarctic Peninsula and the South Shetland Islands. The Strait is partly located on continental crust including areas within the transition to seafloor spreading. The amphibious seismic network BRAVOSEIS is an international effort focused on the seismological research of submarine volcanoes and rift dynamics in the Bransfield Strait. This network is the onshore component of the entire network consisting of 15 broadband land stations deployed in the South Shetland Islands and Antarctic Peninsula between January 2018 and February 2020. The offshore components (network code ZX) include 9 broadband ocean bottom seismometers (OBS) across the Central Bransfield Basin and a group of 6 hydrophone moorings spanning the rift area of 200 x 100 km2, with inter-station distance of ~30 km. Additionally, a smaller offshore array consisting of 15 short-period OBSs with an aperture of 20 km and a narrow inter-station distance of ~4 km was deployed around the Orca submarine volcanic edifice south of King George Island. The data will be used to study the geodynamics of the Bransfield Strait and the evolution of the incipient rifting zone in the domain where extension has been suggested. Seismological methods will include earthquake location, source mechanism, surface wave analysis with ambient noise and earthquake data, receiver function and shear wave splitting. The results may shed light on the crustal structure and tectonic regime in the region and image the location and extent of magma accumulations related to submarine volcanic structures. Finally, the results should provide clues to assess the internal processes that occur in the submarine volcanoes of the area undergoing rifting. Waveform data are available from the GEOFON data centre, under network code 5M and are embargoed until Mar 2024. Acknowledgments: We thank all participants in the BRAVOSEIS 2018, 2019, and 2020 cruises, with a special acknowledgement to Capt. Jose Emilio Regodon and his crew at R/V Hesperides; Capt. Juan Carlos Hernandez and his crew at Sarmiento de Gamboa; Miki Ojeda, Ezequiel Gonzalez, and all the UTM staff involved in the planification and realization of the surveys. We also thank the Spanish Polar Committee and institutions involved in the management of the Spanish Antarctic campaigns and the development of the Spanish Polar Program. We are grateful for the help and support that we always find in the personnel of the Antarctic Bases, especially the Spanish Bases Juan Carlos I and Gabriel de Castilla.

This data publication includes digital data of the final 3D tomographic model from Chen et al. (2020: Lithospheric delamination beneath the southern Puna plateau resolved by local earthquake tomography). The 3D seismic velocity models are results of a local earthquake tomography which is performed to illuminate the crustal and uppermost mantle structure beneath the southern Puna plateau and to test the delamination hypothesis. The Southern Puna is distinctive from the rest of the Central Andean plateau in having a higher topographic elevation, a thinner lithosphere and in being flanked to the south by the Chilean flat slab region. Previous investigations involving geochemical, geological and geophysical observations, have invoked lithospheric delamination to explain the distinctive magmatic and structural history, elevation and lithospheric thickness of the region. In the present study, Vp and Vp/Vs ratios were obtained using travel time variations recorded by 75 temporary seismic stations between 2007 and 2009. The earthquakes catalog (Mulcahy et al., 2014) contains 1903 local earthquakes (25077 P- and 14059 S-picks). A minimum 1D model is derived with software VELEST (Kissling et al., 1995). The 3D tomographic inversion is performed with software SIMULPS (Thurber, 1983; Evans et al., 1994). Spread values are used to define well resolved model domains (6 for Vp and 5.5 for Vp/Vs), which are calculated from the model resolution matrix (Toomey & Foulger, 1989). The data are provided as one tar.gz archive. Individual ASCII files contain, at each depth from 0 to 200 km: - Vp model (model.vp.depth_???km), format: longitude, latitude, depth, Vp perturbation, absolute Vp - Vp/Vs model (model.vpvs.depth_???km), format: longitude, latitude, depth, Vp/Vs perturbation, absolute Vp/Vs - spread values for Vp (spread.vp.depth_???km), format: longitude, latitude, depth, spread value - spread values for Vp/Vs model (spread.vpvs.depth_???km), format: longitude, latitude, depth, spread value

The SWATH-D experiment is dense deployment of 154 seismic stations in the Central and Eastern Alps between Italy and Austria, complementing the larger-scale sparser AlpArray Seismic Network (AASN). SWATH-D will provide high resolution images from the surface into the upper mantle, and allow observations of local seismicity. SWATH-D focuses on a key area of the Alps where the hypothesized flip in subduction polarity has been suggested, and where an earlier seismic profile (TRANSALP) has imaged a jump in the Moho. Where mains power is available (at ca. 80 sites) stations are providing realtime data via the cellphone network and are equipped with Güralp CMG-3EPSC (60s) seismometers and Earth Data Recorders EDR-210. The rest of the stations are offline and consist mainly of Nanometrics Trillium Compact (120s) and Güralp CMG-3EPSC (60s) seismometers equipped with either Omnirecs CUBE3 or PR6-24 Earth Data Loggers. All stations are equipped with external GPS antennas and the sampling rate is 100 Hz (Heit, et al., 2018). The network will operate for 2 years starting in July 2017. The Swath-D data will be used directly by 20 individual proposals of the MB-4D Priority Program (Mountain Building Processes in Four Dimensions, 2017) of the German Research Foundation (DFG) and data products derived from it will contribute to additional 13 proposals. SWATH-D is thus an important link between the MB-4D Priority Program and the international AlpArray communities and a scientific service to many of the proposals within the DFG Priority Program. Waveform data are available from the GEOFON data centre, under network code ZS, and are embargoed until August 2023. After the end of embargo, data will be openly available under CC-BY 4.0 license according to GIPP-rules.

Northwestern Namibia, at the landfall of the Walvis Ridge, was affected by the Tristan da Cunha mantle plume during continental rupture between Africa and South America, as evidenced by the presence of the Etendeka continental flood basalts. Here we use data from a passive-source seismological network to investigate the upper mantle structure and to elucidate the Cretaceous mantle plume-lithosphere interaction. Receiver functions reveal an interface associated with a negative velocity contrast within the lithosphere at an average depth of 80 km. We interpret this interface as the relic of the lithosphereasthenosphere boundary (LAB) formed during the Mesozoic by interaction of the Tristan da Cunha plume head with the pre-existing lithosphere. The velocity contrast might be explained by stagnated and ‘‘frozen’’ melts beneath an intensively depleted and dehydrated peridotitic mantle. The present-day LAB is poorly visible with converted waves, indicating a gradual impedance contrast. Beneath much of the study area, converted phases of the 410 and 660 km mantle transition zone discontinuities arrive 1.5 s earlier than in the landward plume-unaffected continental interior, suggesting high velocities in the upper mantle caused by a thick lithosphere. This indicates that after lithospheric thinning during continental breakup, the lithosphere has increased in thickness during the last 132 Myr. Thermal cooling of the continental lithosphere alone cannot produce the lithospheric thickness required here. We propose that the remnant plume material, which has a higher seismic velocity than the ambient mantle due to melt depletion and dehydration, significantly contributed to the thickening of the mantle lithosphere.

We carried out a passive experiment operated with 10 broadband and short period seismic stations which were installed between July 2013 and May 2015 by a joint effort between the Instituto Andaluz de Geofísica, Granada University and the German Research Centre for Geosciences GFZ. The goal of this project is to study the crustal and upper mantle structures under the Central Betic mountain ranges and the variations of these structures between the different geological domains as a prolongation towards the north of the HIRE profile (Heit, Yuan and Mancilla; 2010). Waveform data is available from the GEOFON data centre, under network code 3J.

We carried out a passive seismic experiment formed by 50 broadband and short-period stations with an interstation distance of 3-4 km. These stations were in operation for 22 months, from 06/2013 to 05/2015. The seismic array (TRANSCORBE) was deployed in a linear configuration of 170 km length in a NW-SE direction. The southern edge of the prolife is located near the Mediterranean coast in Mazarrón (Murcia) crossing the Alhama de Murcia fault and the Cazorla Mountain range in the north. The main goal of this project is to study the crustal and upper mantle structures under the Eastern Betics mountain ranges and their variations along the different geological domains. It probes, from southeast to northwest, the Alboran domain (metamorphic rocks), the External zones (sedimentary rocks) and the Variscan terrains of the Iberian Massif. The proposed scientific work includes the analysis of the data using mainly P and S receiver functions, and velocity and attenuation tomographic techniques. The study area has undergone a complex tectonic evolution where slow WNW-ESE oblique convergence of Iberian and African plates coexists with a rapid westward rollback of a subducting slab. The inter-station distance allows us obtaining high-resolution images of the crustal structure essential to understand the tectonic evolution of the area and how the deformation produced by these processes is distributed among the involved geologic domains. This experiment was the results of a joint effort between the Instituto Andaluz de Geofísica (IAG), Granada University, and GFZ Potsdam. Waveform data are available from the GEOFON data centre, under network code 9H and are embargoed until Jan 2021.

An amphibian passive-source seismic network (WALPASS) have been deployed for a period of two years in the area where theWalvis Ridge intersects with the continental margin of northwestern Namibia. The deployment was intended to study and map the lithospheric and upper mantle structure in the ocean-continent transition beneath the passive continental margin. The main idea is to find seismic anomalies related to the postulated hotspot track from the continent to the ocean along the Walvis Ridge that links the Etendeka continental flood-basalt province to the Tristan da Cunha hotspot in the middle Atlantic ocean. This could provide clues that help us to better understand the role of plume-lithosphere interaction during the continental break-up. We present here first estimates of crustal and lithospheric thicknesses along with a map of distribution of local seismicity in this geophysically little studied region.

The dense deployment of seismic stations so far in the western half of the United States within the USArray project provides the opportunity to study in greater detail the structure of the lithosphere-asthenosphere system. We use the S receiver function technique for this purpose which has higher resolution than surface wave tomography, is sensitive to seismic discontinuities and has no problems with multiples like P receiver functions. Only two major discontinuities are observed in the entire area down to about 300km depth. These are the crust-mantle boundary (Moho) and a negative boundary which we correlate with the lithosphere-asthenosphere boundary (LAB) since a low velocity zone is the classical definition of the seismic observation of the asthenosphere by Gutenberg (1926). Our S receiver function LAB is at a depth of 70-80km in large parts of westernmost North America. East of the Rocky Mountains its depth is generally between 90 and 110km. Regions with LAB depths down to about 140km occur in a stretch from northern Texas over the Colorado Plateau to the Columbia Basalts. These observations agree well with tomography results in the westernmost USA and at the east coast. However, in the central cratonic part of the USA the tomography LAB is near 200km depth. At this depth no discontinuity is seen in the S receiver functions. The negative signal near 100km depth in the central part of the USA is interpreted by Yuan and Romanowicz (2010) or Lekic and Romanowicz (2011) as a recently discovered mid lithospheric discontinuity (MLD). A solution for the discrepancy between receiver function imaging and surface wave tomography is not yet obvious and requires more high resolution studies at other cratons before a general solution may be found. Our results agree well with petrophysical models of increased water content in the asthenosphere, which predict a sharp and shallow LAB also in continents (Mierdel et al. 2007). We are comparing our results from North America with other regions (South Africa, South America, Europe).

On 27 February 2010 the Mw 8.8 Maule earthquake in Central Chile ruptured a seismic gap where significant strain had accumulated since 1835. Shortly after the mainshock a dense network of temporary seismic landstations was installed along the whole rupture zone in order to capture the aftershock activity. We present the aftershock distribution and first motion polarity focal mechanisms based on automatic detection algorithms and picking engines. Processing the seismic data between 15 March and 30 September 2010 from stations from IRIS, IPGP, Caltech and GFZ, we determined 19,908~hypocentres with magnitudes Mw between 1 and 6.2. Seismic activity occurs in six groups: 1.) Normal faulting outer rise events 2.) A shallow group of plate interface seismicity apparent at 25-35 km depth and 50-120 km distance to the trench. Along strike, the aftershocks occur largely within the zone of co-seismic slip but extend ~50 km further north. Along dip, the events are either within the zone of co-seismic slip, or downdip from it, depending on the slip model used. 3.) A third band of seismicity is observed further downdip at 40-50 km depth and further inland at 150-160 km trench perpendicular distance, with mostly shallow dipping thrust focal mechanisms indicating rupture of the plate interface significantly downdip of the co-seismic rupture, and presumably above the intersection of the continental Moho with the plate interface. 4.) A deep group of intermediate depth events between 80 to 120 km depth are present north of 36°S. 5.) The magmatic arc exhibits a small amount of crustal seismicity but does not appear to show significantly enhanced activity after the mainshock 6.) Pronounced crustal aftershock activity is found in the region of Pichilemu (~34.5°S). The time-series of postseismic deformation analyzed here show rapid transient deformation immediately following the Maule earthquake. We examine the relation between the spatial-temporal properties of the aftershock distribution and postseismic displacements from GPS. First results show a linear relationship between cumulative displacement and cumulative number of aftershocks at large times (>25d, when the local aftershock catalog is available). This relationship may be use to infer rheological properties. Similar relations have been observed in other large subduction zone earthquakes.

We present here the results obtained using the data form our passive seismic array in the southern Puna plateau between 25°S to 28°S latitude in Argentina and Chile. In first instance we have been able to calculate P and S receiver functions in order to investigate the Moho thickness and other seismic discontinuities in the study area. The RF data shows that the northern Puna plateau has a thicker crust and that the Moho topography is more irregular along strike. The seismic structure and thickness of the continental crust and the lithospheric mantle beneath the southern Puna plateau reveals that the LAB is deeper to the north of the array suggesting lithospheric removal towards the south. Later we performed a joint inversion of teleseismic and regional tomographic data in order to study the distribution of velocity anomalies that could help us to better understand the evolution of the Andean elevated plateau and the role of lithosphere-asthenosphere interactions in this region. Low velocities are observed in correlation with young volcanic centers (e.g. Ojos del Salado, Cerro Blanco, Galan) and agree very well with the position of crustal lineaments in the region. This is suggesting a close relationship between magmatism and lithospheric structures at crustal scale coniciding with the presence of hot asthenospheric material at the base of the crust probably induced by lithospheric foundering.

Variations in the subduction angle of the Nazca plate beneath the South American plate has lead to the uplift of the Central Andean Plateau. The southern Puna plateau is the southernmost part of this plateau, and one of the transition zones from steep subduction to flat subduction of the Nazca plate. It is characterized by many unique geological and geochemical features with respect to the rest of the Andean plateau, such as a distinct magmatic style, a potentially thinner mantle lid, and a lack of intermediate depth slab seismicity. A major Pliocene delamination event has previously been inferred from geochemical and geological and preliminary geophysical data. The mountain building process of the southern Puna plateau is probably a key to understanding the Andean-type orogenic process. The PUNA passive seismic experiment was operated from the 2007-2009 at southern Puna plateau between 25-28°S. Using the new collected seismic waveform data from PUNA project, we apply the attenuation tomography to resolve both compressional and shear quality factor (Qp and Qs) in the crust and uppermost mantle. The images show a clearly high Q Nazca slab subducting eastward beneath the Puna plateau and another high Q block with a westward dip beneath the Eastern Cordillera, which may indicate the presence of a piece of delaminated South American lithosphere. A significant low Q zone extends between the Nazca slab and South American lithosphere from the northern margin of the array at 25°S and vanishes around 27.5°S. This low Q zone extends further west in the crust and uppermost mantle at the southern end of the array. The low Q zone reaches ~100 km depth beneath the north part of the array, but only ~50 km in the south. The depth of the Nazca slab shows a decreasing trend from north to south beneath the plateau, which is consistent with the steep-flat transition of the angle of the subducting slab.

The central Andes are characterized by significant along-strike variations in magmatism, upper crustal shortening, crustal thickness, and lithospheric structure. Higher resolution regional-scale tomographic imaging of the upper mantle, including the subducting slab and the mantle below it, is required to better understand the relationship between large-scale structural variations and mountain building processes. Multiple temporary seismic networks composed of both broadband and short period stations have been deployed in the central Andes between ~16 to 26°S. The goal of this project is to integrate data from the individual seismic networks in the study region between 1994 and 2008 into a single database and, using modern teleseismic tomography methods, study variations in the upper mantle to depths of ~600 km. P-wave arrivals for teleseismic events between 30° and 90° in three frequency bands (0.2 to 0.8 Hz, 0.1 to 0.4 Hz, and 0.04 to 0.16 Hz) are picked for the broadband stations using a multi-channel cross-correlation algorithm. A single frequency band (0.5 to 1.5 Hz) is picked for the short period stations to help increase the resolution in the study area. Initial results from finite frequency tomography inversions clearly show a trench-parallel fast anomaly with around +2% velocity perturbation. This anomaly migrates to the east with increasing depth and appears to correspond to the steeply dipping subducting slab, penetrating through the 410 km discontinuity. Above 300 km, the slab anomaly exhibits large variations in its amplitude, and we are investigating whether this effect is real or due to uneven data distribution. A large low-velocity anomaly is observed in the uppermost mantle (~100 km) under the southern Altiplano near 21°S extending laterally to the east under the Eastern Cordillera. North and south of this anomaly the upper mantle appears to be more heterogeneous. We are adding to this data set by utilizing additional P-phases to improve the resolution of the images.

We analyse broad-band SS waveformdata recorded by several networks in Europe with sources mainly in the west Pacific to study the underside reflections of teleseismic SS waves in the lithosphere and the upper mantle beneath eastern Asia and the NW Pacific ocean. SS bounce points sample a corridor from the Aleutian, Kamchatka and Japan subduction zones through the North China Craton and Central Asian Orogenic Belt to the Tibetan plateau. The corridor passes through different tectonic units such as subduction zones, an old continental shield, a fold belt and a high plateau. We investigate the seismic structure of the lithosphere and the mantle transition zone beneath the different geotectonic units along the profile and infer the correlation of geodynamic processes at different depths.We explore the short period frequency content in the SS waveform data and use moveout correction and common midpoint stack to acquire profiles with high lateral and depth resolution from the crust to the mantle transition zone. Clear SS precursors of the 410 and 660 km discontinuities show the effects of the interaction between the subducted oceanic lithosphere and the mantle transition zone beneath the NW Pacific subduction zones. A low-velocity layer has also been detected beneath the 410 km discontinuity and can be traced along the entire profile. Due to the improved resolution acquired by the method presented here we have been able to study the shallower structures such as the Moho and the lithosphere–asthenosphere boundary by SS precursors. The continental Moho can be clearly seen along this corridor. The depth variation agrees well with earlier receiver function results. We also see negative reflectors along the profile at varying depths, which can be interpreted as the lithosphere–asthenosphere boundary.

The present project is a joint effort between different institutions to deploy a dense seismic network at Gran Canaria island (Canary Islands, Spain). The interstation distance is around 20 km. The broadband seismic network is composed of one permanent (Guralp CMG-3T 120 s) and five temporary stations (Guralp CMG-3ESP 60 s). The permanent station is a 120 s Guralp CMG-3T and belongs to the Canary Island Seismic Network, run by the Instituto Geográfico Nacional (IGN) of Spain. The temporary stations are 60 s Guralp CMG-3ESP, provided by the GFZ seismic pool. The deployment was carried out in December 2009. The stations will be recording during two years. The improvement of the seismic network allow us to tackle the following issues: the detection and analysis of any local seismicity of tectonic and/or volcanic origin at Gran Canaria island; to contribute to the understanding of the regional seismicity with special interest in the oceanic channel between Tenerife and Gran Canaria Island in collaboration with a project running a dense temporary seismic network in Tenerife; to study the crustal and upper mantle structure, under Gran Canaria to constrain the crustal structure, the source of the volcanism, and better sample the mantle discontinuities and anisotropy. To study the Earth structure, we use receiver function analysis, ambient seismic noise and SKS anisotropy techniques, This project is part of a long-term research of the crustal and the mantle structure of the Canary Islands, which has started with Gran Canaria and Tenerife Islands and will eventually continue with the rest of the archipelago. The origin of the Canary Islands is generally attributed to a broad mantle upwelling under a slow moving plate, resulting in spatially and temporally distributed volcanic activity and a large number of seamounts and islands. A controversial discussion has been going on about the factors that control the evolution of the volcanic edifices, the type of the melting anomaly (a single, well defined mantle plume of a larger area of diffuse mantle upwelling), and the tectonic control of this evolution. This study is foreseen to provide important clues to understand the volcanic structure and tectonic evolution of the Gran Canaria Island.

We study the underside reflections of precursors to SS waves at the lithosphere and the upper mantle beneath eastern Asia. By analyzing the SS bounce points we have been able to investigate the upper mantle discontinuities along a corridor that extends from the Aleutians to the Tibetan plateau passing through Kamchatka, the Japanese subduction zone and the North China craton. One of our aims was to investigate the interaction between the lithosphere and the mantle transition zone beneath different geotectonic units along this corridor and the interaction of geodynamic processes at different depths. In the analysis, we have used the short period content of SS waveform data and methods like CMP stack and migration techniques to acquire high resolution lithosphere and upper mantle images and to improve the lateral and depth resolution for the upper mantle discontinuities. By using a newly developed method we have been able to detect the presence of the continental Moho at different depths along this corridor. We show that the SS precursors provide high resolution images of upper mantle discontinuities such as the 410 and 660 km and the effects of the interaction between the subducted oceanic lithosphere and the mantle transition zone beneath the NW Pacific subduction zone. Furthermore, we show for the first time, that it is possible to create new possibilities to study shallower structures such as the Moho by using the SS precursors.

We study the underside reflections of precursors to SS waves at the lithosphere and the upper mantle beneath eastern Asia. By analyzing the SS bounce points we have been able to investigate the upper mantle discontinuities along a corridor that extends from the Aleutians to the Tibetan plateau passing through Kamchatka, the Japanese subduction zone and the North China craton. One of our aims was to investigate the interaction between the lithosphere and the mantle transition zone beneath different geotectonic units along this corridor and the interaction of geodynamic processes at different depths. In the analysis, we have used the short period content of SS waveform data and methods like CMP stack and migration techniques to acquire high resolution lithosphere and upper mantle images and to improve the lateral and depth resolution for the upper mantle discontinuities. By using a newly developed method we have been able to detect the presence of the continental Moho at different depths along this corridor. We show that the SS precursors provide high resolution images of upper mantle discontinuities such as the 410 and 660 km and the effects of the interaction between the subducted oceanic lithosphere and the mantle transition zone beneath the NW Pacific subduction zone. Furthermore, we show for the first time, that it is possible to create new possibilities to study shallower structures such as the Moho by using the SS precursors.

Preliminary locations for earthquakes recorded by the Central Andean southern PUNA seismic array, which operated between December 2007 and November 2009, show widespread low magnitude seismicity in the region of the well known teleseismic gap between 25°S and 28°S, which is here referred to as the Antofalla teleseismic gap. The southern PUNA experiment, which is a collaboration of Argentine, Chilean, German and U.S. scientists, consisted of 75 stations deployed over an area bounded by 25°S to 28°S and 70°W to 65°W. The US component of the network included 23 broad band and 22 short period seismometers; the German component included 9 broadband and 21 short period seismometers. Previous regional geophysical studies (e.g. Cahill and Isacks 1992) showed a relative lack of crustal earthquakes as well as few large events below 100 km in the Wadati-Benioff zone between 25°S and 28°S. The southern Puna Antofalla gap in teleseismicity is also evident in the current PDE global catalog. Nevertheless, new data from the PUNA network show substantial low magnitude seismic activity (generally

While the Andean cordillera grab most of the seismological attention due to it’s active tectonics, the stable platform is of mainly importance in understanding what could be considered the normal, out of anomaly earth and, may help to understand what are the final and long term results from such a dynamic process like subduction and other types of convergent and divergent plate boundaries interaction. During the last 15 year the Brazilian Lithospheric Seismological Project (BLSP) has been operating more than 60 temporary three-component broadband seismological stations, collecting seismological data mainly in the Brazilian part of the platform. The stations are mainly distributed from 35°W to 60°W and from 10°S to 25°S, covering most of the Parana basin, Tocantins fold beld, Ribeira fold belt and the San Francisco craton. Beyond this central region, there are still some stations distributed over the northern Brazilian margin, covering parts of the Amazon craton and the Parnaiba basin. To complement our dataset we use data from the GT/CPUP station (Vila Florinda/PY FDSN/IRIS). The processing steps included event selection, rotation to LQT coordinate system using an automatic algorithm based on diagonalization of the coherence matrix (for P-wave receiver function only) and deconvolution of the Q by L component for P-wave receiver function and L by Q for S-wave receiver function. The profile images were made by stacking the resulted receiver functions by piercing points locations following pre-defined lines crossing the main tectonic units. At each profile we highlighted the desired Ps and Sp conversion phase for each of the discontinuities and its time readings and errors were estimated by bootstrapping the traces during the stacking procedure. For drawing the conclusions we compared the times each other and with theoretical times computed from the IASPEI91 model and models that presented a ± 5% change in the P- and S-wave mantle velocities. The most important results observed are: 1) A clear cratonic signature, consisting of higher wave velocities for the mantle under the cratons and normal (410km and 660km) depths for the discontinuities 2) Strong presence of the Nazca subducted plate near 410 and 660 km discontinuities under the Southern part of the Parana basin 3) Lack of variation in the Transition Zone thickness and in the mantle velocities due to the presence of the possible plume proposed in 1995 by Vandecar at the Northern Parana basin region and 4) A possible transition zone thinning near the Matiqueira complex, at the Ribeira fold beld, near the Atlantic passive margin.

The central Andean plateau offers an excellent natural laboratory to study mantle flow along an active continental margin as well as the link between plateau uplift and lithospheric delamination. The region between 25°S to 28°S, known as the southern Puna plateau, is characterized by a number of anomalous features possibly indicative of delamination. A total of 43 US and 30 German broadband three component seismic stations were deployed across the southern Puna plateau for approximately two years. The region of study has the advantage of deep and intermediate depth seismicity beneath the array that can be used to constrain the depth distribution of seismic anisotropy in the upper mantle. Teleseismic shear wave splitting results show a transition from east-west fast directions in the east of the array to east-west and north-south in the middle of the array, beneath Galan, and to predominantly north-south in the west part of the array. Azimuthal analysis of local events shows that the events coming from the North of the array split predominantely in the west-south north-east direction. The events coming from the south show splitting into the south-east north-west. Events coming from the West and East show predominant slab parallel splitting. Furthermore, a comparison of the teleseismic and local splitting lag times would suggest the presence of a significant amount of inter- or sub-slab anisotropy. Surface wave measurements indicate the presence of a high velocity block beneath Galan, a very large ignimbrite volcanic center, at depths between 190km (0.007 Hz) and 150 km (0.009 Hz). This can be interpreted as a delaminated block that has resulted in widespread crustal melting. At those same depths there are two high velocity zones, south east and north west of vicuña pampa. At 105 km (0.0125 Hz) we start to see the slab which seems to be deeping to the south. A low velocity zone further east could be responsible for the flatness of the slab at 26°S. At shallower depths, 66 km (0.02Hz), two prominent low velocity zones appear beneath Galan and to the east of Vicuña Pampa. These can be interpreted as post-delamination asthenospheric upwelling. Overall, the mantle beneath the region seems to be isotropic in the western part of the array but anisotropy increases further east. At crustal depths the seismic anisotropy appears to have south-west – north-east fast directions.

En este capítulo presentamos un sumario de las anomalias sísmicas de gran escala determinadas a partir de datos sismológicos por proyectos llevados a cabo en las inmediaciones de la Puna de Jujuy y regiones adyacentes. Estos datos han sido utilizados para definir la geometría de la zona de subducción, determinar el espesor de la corteza y la litósfera, enmarcar zonas de baja velocidad sísmica de ondas P y S (vp y vs) y de alta atenuación sísmica (Q) asociada con la presencia de fluidos y/o material fundido en la corteza y el manto. Han servido tambien para enmarcar zona de alta velocidad de ondas vp y vs con baja atenuación sísmica que indican la presencia de material denso y sin fluidos en la corteza y el manto. La combinación de estos resultados ha proporcionado evidencia acerca de la presencia de cuerpos magmáticos intra-crustales, zonas de fusión en el manto y finalmente de remoción o delaminación cortical y litosférica.