From 24th November 1998 to 24th February 1999 BGR in cooperation with YPF (Yacimientos Petrolíferos Fiscales) and SHN (Servicio de Hidrografía Naval) conducted three seismic surveys along the passive continental margin of Argentine. The seismic vessel M/V Akademik Lazarev which is operated by SMNG (Sevmorneftegeofizika) was used for these cruises. Although the seafloor spreading history of the South Atlantic Ocean is very well defined, the development of the continental margins poses still great problems to a profound understanding. When break-up of Gondwana started in Middle Jurassic, South Africa and South America remained connected. Their break-up started in Early Cretaceous, possibly propagating from south to north. Before break-up, huge tholeiitic flood basalts were extruded near the future rift, namely the Paraná basalts in Brazil and the Etendeka basalts in Namibia. It is likely that these basalts are caused by a large mantle plume. As the flood basalts were predecessors to the break-up, often a causal relationship is assumed. The dipping reflector sequences along large parts of the continental margins of South America and South Africa are interpreted as indications of the plume influence. Investigations along many passive margins have meanwhile shown that dipping reflector sequences exist along most of them. These so-called volcanic margins are the normal ones, the non-volcanic margins are the exception. For many years, it had been assumed that the hydrocarbon potential of volcanic margins is very low. The discovery of the Kudu gas field has demonstrated that this assumption is not valid in general. This increases our interest in continuing the investigation of volcanic passive margins and the variability of their structure along strike. BGR has carried out already two marine geophysical cruises off Argentina, namely with M/V EXPLORA in 1985 and with FS SONNE in 1993. These surveys had shown locally the existence of threefold dipping reflector sequences (Hinz et al., 1999). Furthermore, it had turned out that not everywhere they are accompanied by the strong magnetic G anomaly (Rabinowitz & LaBrecque, 1979). The main objectives of the BGR98 cruise were: (1) Investigation and mapping of the zone of the seaward dipping reflectors (SDR) (reflection + refraction seismic) (2) Investigation of the sedimentary column within this zone (reflection seismic) (3) Setting up a seismostratigraphy based on the seismic records obtained during the cruise and the information from the previous cruises (BGR87, SO85) as well as on additional well information (4) Comparison of the argentine seismic data with seismic data of the conjugate volcanic margin off Namibia (BGR 87). The study area is located offshore Argentine, extending from about 37° 20' S to 45° 40' S and from about 61° 10' W to 52° 00' W. It comprises the Colorado Basin as well as the outermost shelf, slope and rise of the continental margin with water depths up to 5000 m.

During the period from 1974 to 2018 various cruises from BGR acquired seismic lines worldwide. The aim of these marine expeditions was a detailed survey of the geological structure.

In the period from 22nd December, 1987 to 15th January, 1988 a geophysical reconnaissance survey has been carried out with S.V. EXPLORA on the Argentine Eastern continental margin. A total of 3,675 km of digital seismic reflection profiles in parallel with gravimetric and in part magnetic measurements, and 13 sonobuoy refraction profiles were recorded during this survey. The general aim of the survey was to search the Argentine eastern continental margin between 37°S and 47°S for evidence of continent-ocean boundary structures previously recognized by us off South Africa. The following preliminary results were obtained: (1) Five regional seismic markers/unconformities have been observed, named from bottom to top AR V to AR I. (2) Two units are recognizable on all reflection seismic records: A buried lower unit the top of which is marked by the distinct 'AR IV' unconformity of presumably Beriasian/Valangian age, and a tectonically undisturbed upper sedimentary unit. (3) The dominant feature of the lower unit is a 50 km to 100 km broad wedge-shaped body characterized by an internally divergent pattern of reflection horizons having seaward dip. The seismic characteristics and recent ODP drilling is consistent with the wedge being formed from extrusive basaltic rocks. (4) The more than 5000 m thick wedge is parallel with the shelf edge and can be traced continuously for 1200 km. Its landward pinchout coincides with the magnetic slope anomaly 'G'. (5) A giant contourite mound of Neogene age has been recognized in the southeastern part of the survey area. (6) Bottom simulating reflectors have been recognized. Their occurrence is associated with the contourite mound.

On the first leg of SONNE cruise SO-36 in the period from 11th February to 12th March 1985, geophysical investigations have been carried out on the Lord Howe Rise off eastern Australia by the Federal Institute for Geosciences and Natural Resources (BGR) in co-operation with the Bureau of Mineral Resources, Geology and Geophysics, Canberra. A total of 3,660 km of digital seismic reflection profiles, 6,740 km of gravity, magnetics, multibeam echosounder and sub-bottom profiler profiles, as well as 8 sonobuoy refraction profiles were recorded during this survey. A geomagnetic monitoring station of the BGR was operated during a part of the cruise on Lord Howe Island under the supervision of the BMR. These measurements provided a detailed picture of the structures of the survey area of the Lord Howe Rise. The samples proved that the Lord Howe Rise and the Dampier Ridge west of it consist of continental crust. Indications for structures rich in hydrocarbons were not observed. The 2nd and 3rd leg of SONNE cruise SO-36 were designed to investigate the structure, geological development and hydrocarbon potential of two frontier areas, the western and southwestern continental margin of Tasmania and the South Tasman Rise. On the 2nd leg (12.03.-12.04.1985) multichannel seismic reflection measurements were carried out in parallel with magnetic, gravimetric, sea-beam and 3.5 kHz subbottom profiler measurements on 19 lines with a total length of 3,820 km. In addition, 2,140 km were surveyed with magnetics, gravity meter, sea-beam and 3.5 kHz subbottom profiler in transit from and to Sydney, respectively. On the 3rd leg, which started in Sydney on 12th April 1985 and ended in Suva/Fiji one month later, 63 stations were sampled by dredging and coring with the aim (a) to provide lithology and biostratigraphic information about the seismic sequences mapped during leg 2, and (b) to obtain geochemical evidence of hydrocarbon generation from the character of gases absorbed onto the surficial sediment. Samples came from 33 stations off Western Tasmania, from 23 stations on the South Tasman Rise, and from 7 stations in the region of the Lord Howe Rise and the Dampier Ridge. In transit to the sampling sites, 11 single channel seismic lines with a total length of 470 km were surveyed, and in addition, 4,230 km were surveyed with magnetics, gravity meter, sea-beam, and subbottom profiler. Seven regional seismic unconformities were recognized and sampled, and the structural style of both areas was established. Thermogenic hydrocarbons in substantial concentration were found in the surface sediments at the western Tasmanian slope.

Reconnaissance surveys were carried out in 1975 within the framework of the BGR program "Geoscientific studies in the North Atlantic". The data format is Society of Exploration Geophysicists SEG Y. The areas covered were the continental margin of Spitsbergen, the Barents Sea and the Norwegion continental margin. On the vessel LONGVA (30th August, 1975 - 29th September, 1975) multichannel seismic measurements were carried out on 37 lines with a total length of 2,815 km.

In the framework of the IDOE-SEATAR (International Decade of Ocean Exploration - Studies of East Asia Tectonics and Resources) Program, the Federal Institute for Geosciences and Natural Resources carried out a geophysical survey in the Sulu Sea during the period from March 11, 1982 to April 15, 1982 using the German research vessel R/V SONNE. The SONNE cruise no. SO-23 continued SEATAR-related studies of BGR which have been carried out during the Southeast Asian Cruise of the VALDIVIA (VA-16) in 1977. During SONNE cruise no. SO-23, multi-channel reflection measurements were carried out in parallel with magnetic, gravimetric, and sea-beam measurements on 21 lines with a total length of 3,300 km in the Sulu Sea. In the NW Sulu Basin, situated between the shelf of East Palawan in the north and the volcanic Cagayan Ridge in the south, a 50 - 100 km wide graben-like basin exists which is filled with thick Neogene and pre-Middle Miocene sediments. The basin trends east-northeast. At longitude 119°E it bends to a north-south direction. The dominating structural element within the sedimentary graben-like basin is a diapiric-chaotic zone about 25 km wide, which was only detectable west of longitude 120°E. The base of the elongated diapiric-chaotic zone, which might represent a tectonically mobilized equivalent of the Crocker Formation (Middle Miocene - Lower Oligocene) is difficult to define in the seismic monitor records. The configuration and the internal structural style of individual structures of the diapiric-chaotic zone, which can be followed over length of about 150 km, seem to resemble those of the oil-bearing province offshore western Sabah. In the eastern part of the NW-Sulu Basin east of longitude 119°E, several north-trending anticlines of presumably Middle Miocene age and locally volcanic intrusions of presumably Plio-Pleistocene age have been observed. During the second leg of the cruise SO-23 in the southeastern part of the South China Sea (April 16, 1982, to May 9, 1982) multi-channel seismic reflection measurements were carried out in parallel with magnetic, gravimetric, and sea-beam measurements on 19 lines with a total length of 3,570 km in the southeastern part of the South China Sea, including the area of the Dangerous Grounds. In addition, 2,280 km of profile was surveyed with only magnetics, gravity, and sea-beam measurements. A complex structural style was observed in the investigated part of the Dangerous Grounds, South China Sea, which is believed to be part of a microcontinental block which rifted from the continental margin of Asia in the Early Paleogene/Late Mesozoic time. There are prospective depocenters and structures trending NE-SW, E-W, and N-S in the southwestern part, i.e. the area west of longitude 117.5°E (units 2, 3, 4). Unit 4 contains a series of half-grabens with thick sedimentary infill. An imbricated melange of pre-Middle Miocene age seems to exist only off southern Palawan. The dominating structural trend in the area northeast of Reed Bank is NW-SE. Oceanic crust characterized by NW-trending magnetic lineations (anomalies 8 to 12 ?) was observed north of latitude 12°N and between longitude 118°E and the Manila Trench.

The BGR Antarctic cruise 1996 from 29th December 1995 to 6th February 1996 with M.S. AKADEMIK NEMCHINOV was designed to acquire new marine geophysical data for a better understanding of the geological processes, timing, occurrence and location of rifts of the initial break-up of southern Gondwanaland. A total of 3,836 km of multichannel seismic reflection data have been collected in the areas of the Cosmonaut Sea, the Astrid Ridge, the Lazarev Sea and the southern Agulhas Plateau in parallel with magnetic and gravity measurements. In addition magnetic and gravity measurements were carried out on transit. Major new observations of the collected MCS data include: (1) Volcanic rocks play a major part in the construction of the Astrid Ridge and also of the Agulhas Plateau. (2) The early opening of the Lazarev Sea was associated with excessive volcanism resulting in the emplacement of a voluminous volcanic body characterized by an internally divergent pattern of seaward-dipping reflectors. (3) The Astrid Fracture Zone continues in form of a sediment-filled basement depression flanked by distinct basement highs into the Lazarev Sea, and apparently swings to the west parallel to the coast of Queen Maud Land. (4) The thickness of sediments in the Cosmonaut Sea overlying oceanic crust of inferred Early Cretaceous age is in excess of 4s (twt), i.e. about 6,000 m. Three regional seismic markers of inferred Cretaceous, Late Eocene-Oligocene and Middle Miocene ages subdivide the sedimentary column.

The MSM67 SEGMENT research cruise was carried out between August 31st and October 4th 2017 aboard the research vessel MARIA S. MERIAN. Survey MSM67 SEGMENT it is intended to study the architecture of the rifted continental margin off East Greenland around the Jan Mayen fracture zone. Key issues to be addressed are margin segmentation and the location of the continent-ocean transition (COT). Both subjects are highly debated. Symmetric segmentation of conjugate margins has significant implications on our general understanding of continental rifting processes, and a margin-parallel COT off East Greenland would indicate an N-S opening in the Norwegian/Greenland Sea. The latter challenging most publications on the early evolution of the North Atlantic. A major open question is also the timing, duration and distribution of magmatism that resulted in the formation of the North Atlantic large igneous province. Previous suggestions of very short (~3 Myr) periods of intense magmatism have been challenged and a much longer duration and/or a post-breakup origin are under discussion. Here, we want to establish the amount of post-breakup magmatism as evident in high-velocity lower crust and test the dependence of magmatism with distance from the proposed hot-spot under Iceland and the influence of major fracture zones on volcanism.

The expedition PS155/1 started on August 5th, 2018 in Tromsø (Norway) and ended in Longyearbyen (Spitsbergen) on September 3rd, 2018. In the course of BGR’s GREENMATE project the geological development of the European North Atlantic and the northern and north eastern Greenland shelf was analyzed using various marine geophysical methods (seismics, magnetics, gravity, heatflow measurements) and geological sampling (gravity corer, box corer, multi-corer, dredge). Sampling of marine Shelf sediments was undertaken in close correspondence with co-users from Geomar (add-on project ECHONEG), aiming to reconstruct Holocene paleo environmental and climatic evolution. Using the ship’s helicopters, marine sampling was complemented by onshore sampling operations to extract geological material at selected near coastal locations. Other scientific project groups used the cruise PS115.1 as an opportunity to quantify marine mammals and sea birds and their statistical distribution in our research area as part of the long-term project (add-on project Birds& Mammals) and to gather additional meteorological data via radiosondes (add-on Project YOPP). Against all expectations, outstanding ice conditions along the northern coast of Greenland enabled us to carry out reflection seismic surveys north of 84°N at the southern tip of Morris Jesup Rise with a 3 km long streamer. Structural data of this particular region of North Greenland is of special importance for BGR’s project GREENMATE for reconstructing the continental margin evolution. A 100 km long refraction seismic profile was measured to complement the reflection seismic data. After completing this, scientific work was concentrated on the northeastern Greenland shelf area between 76°N and 82.5°N. Over the time of the cruise a total of 2500 km of reflection seismic profiles (2250 km measured with 3km streamer length) and 100 km of refraction seismic profile (using nine ocean bottom seismometers) were measured, accompanied by gravity and magnetic surveys and seven heat flow measurement stations. Along the shelf and deep-sea area 21 geological sampling sites were chosen, with all together one dredge (around 200 kg of sample), 16 gravity cores (total core length 65 m), 12 box corers and 6 multi-corer stations. Onshore sediment sampling was done at 11 sampling sites. Beside sediment sampling hard rock from near coastal outcrops was collected in a total amount of 250 kg that will be used for age dating. The entire science program was carried out under consideration of the highest ecological standards to protect marine mammals and to meet all environmental requirements of the permitting authorities. In addition to external marine mammal observers (MMO) various acoustic monitoring systems and AWI’s on board infrared detection system AIMMS monitored any activity of marine mammals in the ships perimeter, especially during seismic operations.

The main goals of the project SO231-PAGE4 were an improved understanding of Gondwana break-up and to analyze timing, structures and kinematics of ancient to modern Extension along the East African continental margin. During the cruise SO231 from 20th February 2014 (Durban) to 29th March 2014 (Durban), a total of 4300 km of geophysical profiles has been acquired. The processed (migrated) profiles are available in SEG-Y Format.