A geophysical reconnaissance survey across oceanic fracture zones has been carried out by the BGR in the eastern North Atlantic using S.V. PROSPEKTA. The geophysical measurements, including multichannel seismic reflection profiling, magnetics and gravity were concentrated on three oceanic crustal areas of Mesozoic crust which are crossed by the Hayes Fracture Zone, the Atlantis Fracture Zone and the Kane Fracture Zone respectively. 24 geophysical lines with a total length of 5,362 km have been measured during the time period from 25th October to 4th December 1985. Besides intracrustal seismic events a deep coherent seismic event is often recognizable in the monitor records between 10 - 12 s (TWT) along several lines, which probably is a reflection from the crust-mantle boundary.
During the period from 1974 to 2018 various cruises from BGR acquired seismic lines worldwide. The aim of these marine expeditions were a detailed survey of the geological structure of seabed.
The cruise leg MSM09/3 was conducted as a cooperative project between the Alfred Wegener Institute for Polar and Marine Research (AWI), the Federal Institute for Geosciences and Resources (BGR), the Geological Survey of Denmark and Greenland (GEUS) and Dalhousie University. The data format is Society of Exploration Geophysicists SEG Y. A geophysical survey covered areas of Baffin Bay and Davis Strait between Greenland and the Canadian Baffin Island. A component of the IPY 2007/08 Lead Project Plate Tectonics and Polar Gateways in the Earth System (PLATES & GATES), this project DAVIS GATE is aimed to develop a tectonic and sedimentary reconstruction of the opening process of this oceanic gateway. Baffin Bay and Davis Strait play an important role in the shallow water exchange from the Arctic to the Atlantic Ocean. The plate-tectonic evolution as well as the magmatic history of this region has been sparsely known and required a careful geophysical investigation in order to construct a set of gridded detailed paleotopographic maps for a complete geodynamic reconstruction of this gateway. With a set of three seismic refraction/wide-angle reflection profiles, using ocean-bottom seismometers on 62 stations, as well as multi-channel reflection seismic recordings with a 3000-m long streamer, data were acquired from the sedimentary cover to the deep crust and even from parts of the uppermost mantle. Additional seismic data supplement these profiles and provide insights into the structures of the basement and dominant fault zones such as the Ungava fault system. A parallel running magnetic survey aimed to resolve the temporal evolution of the oceanic crust of Baffin Bay. The extension and subsidence of the continental and transitional crust in the Davis Strait and the evolution of oceanic crust in the Labrador Sea and Baffin Bay could be investigated with dataset to which continuously recorded gravity anomaly data and sub-bottom profiler data also contribute. This dataset provides the basis of geometrical and physical properties of the crust required for a realistic geodynamic model which will describe the break-up and the ocean basin evolution between Greenland and Canada in terms of detailed paleo-topography.
Within the framework of the research project SINDBAD (Seismic and Geoacoustic Investigations Along the Sunda-Banda Arc Transition) marine geophysical investigations have been carried out with RV SONNE from October 9th, 2006, to November 9th, 2006, off the eastern Sunda Arc and at the transition to the Banda Arc in Indonesia. The research cruise SO190 Leg 1 started in Jakarta, Indonesia and ended in Darwin, Australia. During this cruise, multichannel seismics (MCS), magnetics (M), and gravimetry (G) measurements have been carried out. Simultaneously, SIMRAD (multibeam echosounder) and PARASOUND (sediment echosounder) data have been collected using RV SONNEs onboard systems. During the expedition, a total of 4,933 km of profiles with MCS, M, and G have been acquired. Six of the 20 profiles are long overview profiles perpendicular to the deformation front and cover the entire forearc from the forearc basin across the outer arc high, the deformation front onto the oceanic lithosphere. Additional profiles have been acquired along strike in the Lombok forearc basin and in the Savu Basin. The main goal of the project SINDBAD is to investigate the relation between the variability of the lower plate and the tectonic evolution of the overriding plate (formation of an outer arc high, development of forearc basins, and accretion and erosion processes of the overriding plate). The "raw materials" – seafloor sediments, oceanic crust (at the Banda Arc also continental crust) and mantle lithosphere – are carried into the subduction system at the trench. The influence of these "raw materials" on the overriding plate is controlled by a number of factors: e.g. the convergence rate, the obliqueness of convergence and the physical and chemical properties of the lower plate (e.g. its age, its sediment-cover and –thickness, its fluid content and the composition of the crust). Forearc basins are today attracting increased attention because of their hydrocarbon potential. The forearc basins of the eastern Sunda Arc are still frontier areas which are almost unexplored. An additional goal of this project is therefore the assessment of the hydrocarbon potential of the Lombok Basin. In contrast to the Sumatra subduction zone, only a small amount of pelagic sediment is carried into the subduction system offshore East Java, Bali, Lombok, Sumbawa and Sumba. This results e.g. in a less pronounced development of the outer arc high, which is subaerial off Sumatra, but entirely below the sea surface in the eastern Sunda Arc. The Roo Rise, which is subducting off East Java, is a morphological high that lies about 1500 m higher than the Argo Abyssal Plain which is subducting further to the east. Despite of these pronounced differences, the deformation front in both areas shows similarities. While the foot of the slope shows lower dip than the upper slope, both areas are characterized by landward dipping thrust sheets. In both areas the outer arc high is characterized by active faults (the recent activity is indicated by deformed basin sediments on the outer arc high) and therefore no indications for a static backstop have been found. The accretionary character of the deformation front is clearly indicated in both areas, while subrosion in association with the subsidence of the Lombok Basin can not be excluded based on the preliminary interpretations. The trench in both areas is devoid of sediments, which indicates erosional processes caused by currents along the trench strike. However, a depocenter for these sediments could not be localized yet. While a forearc basin is not clearly developed off East Java, the Lombok forearc basin with water depths of more than 4000 m extends from off Bali to off Sumbawa. On the southern slope of the basin prograding sedimentary sequences indicate uplift, probably caused by the subducting Roo Rise or a growth of the outer arc high. Additionally, carbonate platforms on the acoustic basement indicate phases of rapid subsidence of the basin. The sediment thickness reaches a total of about 3.5 sec TWT. A few seismic "bright spots", but no bottom simulating reflectors (BSRs) have been identified in the basin. The profiles striking along the basin axis indicate paleo-depocenters in the western part of the profile, while the recent depocenter is located in the eastern part of the basin. On the northern flank of the Lombok basin, indications for submarine volcanism (recent activity is unknown) are indicated by a seamount reaching above the seafloor associated with a clear magnetic anomaly. East of the Lombok Basin the island of Sumba is located, which is regarded as a microcontinent that has been attached to the island arc during the Late Oligocene. Sumbas geographical location in front of the island arc is usually characterized by the location of a forearc basin and correlates with the seaward displacement of the deformation front (Roti Basin) at the transition from ocean/island arc subduction of the Sunda Arc to continent/island arc collision of the Banda Arc. An uplift of about 0.5 cm/a is reported for Sumba, associated with the underplating of the continental Scott Plateau. The uplift is especially evident in the MCS data. To the east of the Lombok Basin depocenter, a transition zone with deep reaching faults is observed, associated with eastward dipping sedimentary and basement structures. This transition zone is also indicated by anomalies in the magnetic and gravity data, the latter indicating isostatic undercompensation. On the western flank of Sumba, deformed sedimentary sequences indicate gravitational gliding in association with the uplift of Sumba. East of Sumba, two profiles into the Savu Basin have been acquired. Here the uplift of Sumba is indicated by the erosion of sedimentary sequences which have been deposited in the basin followed by uplift and subsequent erosion. Further indications of "inversion structures" are given by a reactivated thrust fault that in the past has served as the southern boundary of the Savu Basin und indicates recent activity by associated deformed basin sediments. The oceanic crust of the Argo Abyssal Plain and the Roo Rise is characterized by thin sediments. On a connection profile between two long profiles on the Argo Abyssal Plain a basin with about 1.4 sec TWT of sediment has been observed, that, indicated by a magnetic anomaly, can be correlated with an age jump of about 15 Ma, thereby indicating a paleo plate boundary.
The first country wide soil map at a scale of 1:1,000,000 (BUEK1000) has been compiled on the basis of published soil maps of the former German Democratic Republic and the pre 1990 federal states of Germany. To do this, it was necessary to match the soil systems used in East and West Germany and to develop standardized descriptions of soil units. A relatively homogeneous map has resulted, which permits uniform assessment of the soils throughout Germany. The map shows 71 soil mapping units, described in the legend on the basis of the German and FAO soil systems. Each soil unit has been assigned a characteristic soil profile (Leitprofil) as an aid to map interpretation. For the first time the subdivision of the country into 12 soil regions has been represented on the map. This subdivision was coordinated with the state Geological Surveys. These soil regions will represent the highest hierarchic level of nation wide soil maps in future. The colours of soil units correspond to the standards of the 'Bodenkundliche Kartieranleitung' (KA 3; Guidelines for Soil Mapping). The various hues characterize differences in relief or soil humidity. The BUEK1000 was produced digitally. It is an important part of the spatial database integrated in the Soil Information System currently being established at the Federal Institute for Geosciences and Natural Resources (FISBo BGR). It can be used together with the characteristic soil profiles to derive thematic maps related to nation wide soil protection. The scale of the BUEK1000 makes it especially suitable for small scale evaluations at federal or EU level.
The cruise BGR95 from 19th November to 28th December 1995 with M.S. AKADEMIK NEMCHINOV was designed to acquire new marine geophysical data for a better understanding of the geological processes and structural variations of the Cretaceous-aged oceanic crust of the Angola Basin in the South Atlantic regarding its reflectivity pattern, its shape of the basement surfaces and its crustal thickness. These evaluations were extended onshore to the ‘Damara Igneous Province’. The aim of this study was the investigation of the rift-related volcanic-magmatic processes accompanying the initial stage of the opening of the South Atlantic Ocean. The survey was a co-operation of BGR, Alfred Wegener Institute for Polar and Marine Research (AWI), GeoForschungsZentrum Potsdam, University of Göttingen and Johann Wolfgang Goethe-University Frankfurt/Main. The M.S. AKADEMIK NEMCHINOV generated the seismic signals by a tuned airgun array of 3260 cu.in. (= 53.4 l) together with two AWI owned large volume guns of 2 x 2000 cu.in. (= 65.6 l), recorded the MCS signals with a 3000 m streamer and controlled the shot releases for the ocean bottom hydrophones (OBH’s) and the onshore seismic stations (PEDAS). A total of 5,114 km of multichannel seismic reflection data in parallel with magnetic and gravity measurements have been collected onboard the M.S. AKADEMIK NEMCHINOV. 1069.4 km of the seismic work was done on 3 combined refraction/wide angle offshore and onshore traverses. The offshore part was recorded by 7 ocean bottom hydrophones (OBH) operated by the M.V. POLAR QUEEN (Reichert et al., 1996). The registration onshore Namibia was performed by 25 mobile seismic landstations (PEDAS) on each profile (Schulze et al., 1996). First results are described in the offshore and onshore reports of these investigations (Reichert et al., 1996, and Schulze et al., 1996). The data clearly show distinct series of the seaward dipping reflector sequences (SRDS) and isochronous variations in the accretion of the oceanic crust. The onshore and offshore registrations show deep arrivals from diving and refracted waves in a range up to 200 to 400 km.
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.
Processed seismic data from Baltic Sea with research ship M/V Polar Queen.The data format is Society of Exploration Geophysicists SEG Y. During the period from 14th to 28th of April 1996 BGR and GFZ chartered the Norwegian vessel M/V POLAR QUEEN for testing the new and updated marine seismic equipment of the BGR and for acquiring seismic lines. The operating area was the North Sea and Baltic Sea. The geophysical lines in the Baltic Sea were chosen as extended onshore DEKORP lines to evaluate the deep structure of the south western part of the Baltic Sea. For the seismic profiles a tuned source array consisting of 20 air guns in two linear strings with a total volume of 52 l was used. The recording length was 26 s, the sample rate 4 ms and the shot interval 30 s. This time triggering for the shot release was chosen, because all shots were also recorded onshore by seismic stations for wide angle/refraction acquisition (GFZ). During this leg 810 km reflection lines and additional 230 km pure shooting could be surveyed. The preliminary interpretation of the seismic single traces was restricted on the ship to the upper time range. The main structures in the southern Baltic Sea could be evaluated. A full interpretation especially of the deeper part is only possible after a processing due to the nature of the single traces and the S/N ratio.
The Scientific staff and crew onboard CCGS Louis S. St. Laurent (LSL) returned September the 10th, 2001 from a scientific expedition to the Nares Strait, the northernmost waterway connecting the Arctic and Atlantic oceans. The data format is Society of Exploration Geophysicists SEG Y. The ice conditions in the strait required the support of Canada's largest ice breaker. The ship was a versatile platform for 34 scientists to accomplish their marine investigation. The LSL has a history of supporting international scientific expeditions including an oceanographic transect of the Arctic Ocean in 1994 and a biological study of the Canadian Arctic Islands in 1999. Germany (Bundesanstalt für Geowissenschaften und Rohstoffe, BGR) and Canada (Geological Survey of Canada) undertook a 5-week scientific cruise to study and explore the geological structure and evolution of the Nares Strait. The primary objective was the study of structural features relating to the formation of the Arctic Ocean and, in particular, the study of the Wegener Fault. This fault is a linear boundary between Greenland and Ellesmere Island which was noted by the German scientist Alfred Wegener in 1915 and later became the subject of a major scientific controversy. The co-operative cruise, which was planned over a period of 2 years, provided the basis for a wide range of scientific investigations, from marine seismic work and climate change studies through airborne magnetic investigations to geodetic survey measurements and geological sampling onshore. Systematic geophysical offshore studies in this key area had not been undertaken before. Where towing of seismic equipment was not possible because of ice coverage, magnetic maps were made using a helicopter-borne magnetic sensor system. Sediment and water samples taken during the cruise provide information on changes in climate and sea ice cover from the last ice-age to the present. An 11 m-long sediment core from outer Jones Sound is the longest core ever taken in the Canadian Arctic channels and holds clues to the detailed climate history of northern Baffin Bay.
The SONNE cruise SO-49/1 from 6th April to 7th May 1987 was designed to investigate the Cotabato subduction zone off Mindanao and the geological structure of the eastern part of the Sulu Sea including the convergent continental margins off Zamboanga Peninsula, Negros, and Panay by a geophysical survey. On the 1st leg multichannel seismic reflection measurements were carried out in parallel with magnetic, gravimetric, sea beam and 3.5 kHz subbottom profiler measurements on 16 lines with a total length of 2,700 km. The SONNE cruise SO-49/1 was financed by the Federal Ministry of Research and Technology (BMFT). The geophysical survey in the Celebes Sea and in the Sulu Sea was carried out as a co-operative project by the Federal Institute for Geosciences and Natural Resources (BGR), the Bureau of Mines and Geoscience (BMG) and the Bureau of Energy Development (BED). 16 German scientists and technicians and 4 Philippine scientists attended SONNE cruise SO-49/1. The seismic lines surveyed across the Cotabato Trench/Celebes Sea and the Sulu Trench/Sulu Sea illustrate the active deformation of the layered sediments of the Celebes Sea and the SE Sulu Basin along the trenches: The seismic data suggest an active development of imbricate thrust sheets at the toe of the accretionary wedges and a simultaneous duplex-kind shortening within the wedges above the downgoing oceanic crust of the Celebes Sea and the SE Sulu Basin. The surface of the downgoing oceanic crust forms a major detachment plane or sole thrust. By these processes mass is added to the accretionary wedges resulting in thickening and growing of the wedges. The sedimentary apron overlaying the wedge is only mildly affected by these processes because the surface of the accretionary wedges forms a roof thrust. The collected geophysical data suggest that the oceanic SE Sulu Basin previously extended northward into Panay Island. It was closed by eastward subduction of oceanic crust beneath the upthrusted/updomed Cagayan Ridge. The Negros Trench, a 4.000 to 5,000 m deep bathymetric depression, is thought to represent the collision suture of the opposed subduction systems. The Cagayan Ridge which divides the Sulu Sea into the NW Sulu Basin and the SE Sulu Basin continues into the Antique Ridge of Panay. Approximately 45 suitable and problem-oriented sampling locations have been defined and documented for the subsequent geological and geochemical program by on-board analysis and interpretation of the seismic near trace records and the recordings of the 3.5 kHz subbottom profiler and the sea beam system. On cruise SO49/2 from 10th May to 21st June 1987, the research vessel SONNE of the Federal Republic of Germany undertook geoscience cruises in the South China Sea. The multidisciplinary study of the tectonic and natural resources of the region was a cooperative project between the Federal Institute for Geosciences and Natural Resources (BGR) and the Second Institute of Oceanography (SIO) in the frame of the Agreement between the State Oceanic Administration of the People's Republic of China and the Federal Ministry for Research and Technology of the Federal Republic of Germany on Cooperation in Marine Science and Technology. The first part of cruise SO49/2 was primarily to acquire multichannel seismic data, together with gravity, magnetic, sea beam, and 3.5 kHz measurements, and consisted of 4,112 km of traverses across the deep eastern and western sub-basins of the South China Sea from the Dangerous Grounds to the Chinese continental margin. The observed complex crustal deformation in the Southwestern South China Sea basin and in particular deep intracrustal reflection suggest a large-scale simple-shear kinematic mechanism for the development of at least the western sub-basins. The second part of cruise SO49/2 had primarily geological, geochemical and geothermal objectives and 21 dredge stations, 17 geochemical stations and 6 heat flow stations were carried out. The aims of the sampling were firstly to determine the lithologies and ages of the seismic sequences, and secondly to collect unconsolidated sediments for geochemical study of sorbed hydrocarbon gases in combination with heat flow measurements. Late Oligocene shallow-water carbonates dredged from 700 m to 2700 m of water depth indicate a strong subsidence of the investigated area. The underlying basement consists of continental crust with basaltic intrusions. The hydrocarbon gases of the outer continental slope originated by thermogenic processes from source rocks with a predominantly high maturity of the organic substances.
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