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The GeoSEA array is a network of seafloor transponders used in direct path measurements at water depths up to 6.000 m. Direct path acoustic ranging with baselines up to 2.500 m resolves seafloor deformation at high resolution (< 5mm repeatability). The array is configured for continuous interrogations to monitor the state of seafloor deformation, e.g. at volcanic flanks, active faults or continental slopes. Data retrieval may be conducted via an acoustic modem using a vessel or a surface vehicle (wave glider) as a platform. The GeoSEA array consists of 34 acoustic transponders, which have been deployed in various tectonic settings. One network monitored the stress build up along the North Anatolian Fault offshore Istanbul in the Sea of Marmara, indicating a potential slip deficit of up to 2.5 m. No right-lateral creep was detected, indicating a locked or very moderately creeping fault segment which is currently accumulating strain. Three networks consisting of 8, 10 and 5 transponders, respectively, were installed in 2015 on the continental slope and outer rise of the North Chilean subduction zone and were recovered in 2022. The arrays were positioned in water depths between 2.400 m to 5.200 m using the deep-sea cable of RV SONNE. A further scientific target was the instable eastern flank of Mt Etna volcano in Italy, where up to 6 transponders were installed in 2016 in recurrent campaigns. We provide an overview of the monitoring strategy for these different campaigns and the main results of the direct path ranging., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

This dataset includes five stations of an Ocean Bottom Seismometer (OBS) experiment conducted at the southern end of the Fonualei Rift and Spreading Center in the Lau Basin, southwestern Pacific. The OBS recorded continuously for 32-days on 4 components, including a hydrophone and a 3-component 4.5 Hz geophone. The experiment was conducted during RV Sonne cruise SO267, project ARCHIMEDES I. In the article, the authors report an increasing trend of methane emissions for June and July at a permafrost site in Siberia (Lena River Delta). Using the longest set of observational methane flux data in the Arctic, the authors demonstrate that the continuous warming has begun to trigger the projected enhancement of methane release in Arctic permafrost ecosystems. This software is written in MATLAB. Running the codes ([.m files](Code)) and loading the data files ([.mat files](Data)) requires the pre-installation of [MATLAB](/https://de.mathworks.com/products/matlab.html). IMPORTANT: The repository only contains dummy data. The data that is needed to run the code can be requested by Torsten Sachs and Christian Wille (contact authors). Although the scripts and the data files have been tested for newer versions of MATLAB (>= MATLAB R2017a). The code might also run in older versions of MATLAB, but this has not been tested.

The northeastern Lau Basin is one of the fastest opening and magmatically most active back‐arc regions on Earth. Although the current pattern of plate boundaries and motions in this complex mosaic of microplates is reasonably understood, the internal structure and evolution of the back‐arc crust are not. We present new geophysical data from a 290 km long east‐west oriented transect crossing the Niuafo'ou Microplate (back‐arc), the Fonualei Rift and Spreading Center (FRSC) and the Tofua Volcanic Arc at 17°20′S. Our P wave tomography model and density modeling suggest that past crustal accretion inside the southern FRSC was accommodated by a combination of arc crustal extension and magmatic activity. The absence of magnetic reversals inside the FRSC supports this and suggests that focused seafloor spreading has until now not contributed to crustal accretion. The back‐arc crust constituting the southern Niuafo'ou Microplate reveals a heterogeneous structure comprising several crustal blocks. Some regions of the back‐arc show a crustal structure similar to typical oceanic crust, suggesting they originate from seafloor spreading. Other crustal blocks resemble a structure that is similar to volcanic arc crust or a “hydrous” type of oceanic crust that has been created at a spreading center influenced by slab‐derived water at distances, Key Points: First insights into the crustal structure of the northeastern Lau Basin, along a 290 km transect at 17°20′S. Crust in southern Fonualei Rift and Spreading Center was created by extension of arc crust and variable amount of magmatism. Magmatic underplating is present in some parts of the southern Niuafo'ou Microplate., Bundesministerium für Bildung und Forschung (BMBF) http://dx.doi.org/10.13039/501100002347

The nature of the Ionian Sea crust has been the subject of scientific debate for more than 30 years, mainly because seismic imaging of the deep crust and upper mantle of the Ionian Abyssal Plain (IAP) has not been conclusive to date. The IAP is sandwiched between the Calabrian and Hellenic subduction zones in the central Mediterranean. A NNESSW-oriented 131 km long seismic refraction and wide-angle reflection profile, consisting of eight ocean bottom seismometers and hydrophones, was acquired in 2014. The profile was designed to univocally confirm the proposed oceanic nature of the IAP crust as a remnant of the Tethys and to confute its interpretation as a strongly thinned part of the African continental crust. A P-wave velocity model developed from travel-time forward modelling is refined by gravimetric data and synthetic modelling of the seismic data. A roughly 67 km thick crust with velocities ranging from 5.1 to 7.2 km s-1, top to bottom, can be traced throughout the IAP. In the vicinity of the Medina seamounts at the southern IAP boundary, the crust thickens to about 9 km and seismic velocities decrease to 6.8 km s-1 at the crustmantle boundary. The seismic velocity distribution and depth of the crust mantle boundary in the IAP document its oceanic nature and support the interpretation of the IAP as a remnant of the Tethys lithosphere with the Malta Escarpment as a transform margin and a Tethys opening in the NNWSSE direction.

Raw-, SEG-Y and other supplementary data of the landside deployment from the amphibious wide-angle seismic experiment ALPHA are presented. The aim of this project was to reveal the crustal and lithospheric structure of the subducting Adriatic plate and the external accretionary wedge in the southern Dinarides. Airgun shots from the RV Meteor were recorded along two profiles across Montenegro and northern Albania.

Zusammenfassung Desmopressin (DDAVP) wurde 1966 als Abkömmling des antidiuretischen Hypophysenhormons Arginin-Vasopressin synthetisch hergestellt. Zu den antidiuretischen Indikationen zählen Diabetes insipidus und Enuresis nocturna, zudem wird es in Tests zur Bestimmung der Nierenkonzentrationsfähigkeit verwendet

RV SONNE cruise SO244-2 sailed offshore northern Chile from Nov. 27 to Dec. 13, 2015 to install the seafloor geodetic network GeoSEA (Geodetic Earthquake Observatory on the SEAfloor) on the marine forearc and outer rise of the South American subduction system around 21°S. This segment of the Nazca-South American plate boundary has last ruptured in an earthquake in 1877 and was identified as a seismic gap prior to the 2014 Iquique/Pisagua earthquake (Mw=8.1). The southern portion of the segment remains unbroken by a recent earthquake and is currently in the latest stage of the interseismic phase of the seismic cycle. Seafloor geodetic measurements provide a way to monitor crustal deformation at high resolution comparable to the satellite-based GPS technique upon which terrestrial geodesy is largely based. The GeoSEA Network consists of autonomous seafloor transponders installed on 4 m high tripods, which were lowered to the seabed on the deep-sea cable of RV SONNE. The transponders within an array intercommunicate via acoustic signals for a period of up to 3.5 years. An additional component of the network is GeoSURF, a self-steering autonomous surface vehicle (Wave Glider), which monitors system health and is capable to upload the seafloor data to the sea surface and to transfer it via satellite. We have chosen three areas on the middle and lower slope and the outer rise for the set-up of three sub-arrays. The array in Area 1 on the middle continental slope consists of 8 transponders located in pairs on four topographic ridges, which are surface expressions of faults at depth. Area 2 is located on the outer rise seaward of the trench where 5 stations monitor extension across plate-bending related normal faults. The third area is located at water depth >5000 m on the lower continental slope where an array of 10 stations measures diffuse strain build-up. Data from all networks and all stations were successfully uploaded to GeoSURF and/or a HPT modem lowered into the water from RV SONNE. The seabed installation of a total of 23 transponders was completed by December 07, when we proceeded to deploy a total of 14 ocean bottom seismometers (OBS) on the forearc between 19.2°-21.6°S. These instruments will be recovered by RV LANGSETH in Spring/Summer 2016.