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Processed seismic data of Cruise SO98 GIGICS 1994

Main target of the project GIGICS (Cooperative German-Indonesian Geoscientific Investigations in the Celebes Sea) is the investigation of the internal crustal structure and the plate tectonic evolution of the Celebes Sea and its active continental margins off Mindanao and Northern Sulawesi. These investigations were carried out during the cruise SO98 of RV SONNE by the Federal Institute for Geosciences and Natural Resources (BGR), Hannover; the German Research Centre for Geosciences (GFZ), Potsdam; the GEOMAR, Kiel; the Institute of Oceanography (IfM), Hamburg; the Mines and Geoscience Bureau, Manila; the Agency for the Assessment and Application of Technology, Jakarta, and the Institute of Oceanography, Wormley. The cruise SO98 consisted of three legs of two weeks duration and one leg of four weeks duration. The total amount of data acquired during the cruise were: - 3,300 km of multichannel reflection seismics, - over 6,800 km of gravimetric and magnetic data and approximately 10.000 km of swath bathymetric and sediment echosounder data, - 3 wideangle-/refractionseismic profiles, each of 120 - 150 km length, - geological, geochemical sampling and oceanographical measurements at a total of 37 stations. During the cruise SO98 a widespaced but regular grid of magnetic and gravimetric profiles were acquired in the eastern part of the Celebes Sea from which up to then reliable data were very sparse. WEISSEL (1980) recognized in the western Celebes Sea WSW-ENE striking magnetic lineations, which he interpreted as chrons 18 - 20 (39 - 43 Ma according to the timescale of HARLAND et al. (1990)). The data from cruise SO98 show that there is no continuation of these anomalies to the east. In the eastern part the magnetic field of the Celebes Sea is less clear and much more disturbed. Nevertheless, E-W-striking anomalies are recognizable. Because amplitudes of local magnetic anomalies are higher than the lineations, the correlation of these lineations with the magnetic reversal scale is still somewhat ambiguous. The gravity map compiled from the measured gravimetric data shows elongated positive anomalies in the eastern part of the Celebes Sea. Exceptions occur at the deep sea trenches off North Sulawesi (North Sulawesi Trench) and Mindanao (Cotabatu Trench) and at the Sulu Archipelago where strong negative gravity anomalies were found. A remarkable NW-striking gravity high of up to 60 mgal was found in the central eastern part of the Celebes Sea. Gravimetric modelling suggests that this high can be correlated with the gravimetric effect of the Molucca Sea Plate subducting from the east under the Sangihe Arc. The reflection seismic data from the northern part of the Celebes Sea show indications for a juvenile subduction of oceanic Celebes Sea crust under the Sulu Archipelago. The oceanic crust bends down towards the Sulu Arc with angles between 2° and 5° and the sedimentary sequence above is deformed indicating a compressional stress regime. With the exception of two linear arranged seamount-like basement highs the Celebes Sea is dominated by two different oceanic crustal types showing distinct differences in the topography. The first one is showing a very similar reflection seismic pattern as it is found for oceanic crust of the Atlantic (HINZ et al., 1994). This type is characterized by a small-scale block-faulted relief of the top basement and a low reflectivity in lower crustal levels typically related as to be accreted at slow to intermediate spreading ridges. This type is found in the western, northern and southern part of the investigated area. In the eastern and especially in the southeastern part the igneous crust shows a very different image. The reflection of the top of the basement is less distinct and of lower frequency. The relief is very much smoother than in the previous type. This reflection seismic image indicates a volcanic/magmatic overprinting of the oceanic crust in this part of the Celebes Sea. Another target of cruise SO98 was the area of the active continental margin off North Sulawesi and its accretionary complex. The internal structure of the accretionary complex should be investigated to decide whether this active margin is also of the 'splinter-type' or not. During former geophysical cruises with RV SONNE oceanic crustal splinters were discovered in the accretionary wedges of the Sulu Sea and off Costa Rica (e.g. HINZ et al., 1991). From our reflection seismic measurements this active continental margin is morphologically subdivided into three units and consists of two accretionary complexes of different internal structural style: the lower and middle continental slope is underlain by an intensively thrusted, sedimentary accretionary wedge. This wedge was most probably formed during the last 5 Ma. Landward of this wedge an older and seismically very complex accretionary unit is present which is overlain at its landward termination by a sedimentary fore-arc basin. Within this older accretionary complex, units with a strong, low frequency reflection pattern were found which are interpreted to represent crustal splinters of igneous oceanic or ophiolitic nature. This interpretation is supported by our gravity and magnetic data. The magnetic profiles show an increase of the magnetic field towards the north arm of Sulawesi across the continental margin. This increase of the magnetic field suggests an increase of magnetized material within the older accretionary wedge towards the northern arm of Sulawesi where ophiolites are emplaced. During the interpretation of the reflection seismic data of the project GIGICS BSR's (bottom simulating reflectors) were discovered for the first time along the active continental margin of North-Sulawesi. BSR's are the seismic expression of a velocity decrease at the bottom of a gas hydrate zone. The distribution and depth of the BSR's correlates with the geochemical and geothermal results. Radiometric age dating and geochemical analyses from pillow basalts of a seamount from the southeastern Celebes Sea indicate hot-spot activity in this part of the Celebes Sea during or shortly after the formation of the oceanic crust approximately at 43 Ma ago. Three NW-striking ridges or seamount-chains in the northeastern Celebes Sea were mapped and investigated in detail. They are thought to represent a wrench fault system extending through the northeastern Celebes Sea. At the flank of one of these ridges a strongly alterated plagioclase-olivine basalt sample was dredged which was overlain by non-fossiliferous clay stone. A similar lithostratigraphic sequence was drilled during ODP leg 124 (RANGIN et al., 1990). The geochemical composition of these basalts is different from typical MORB. The existence of a large crustal splinter within the accretionary wedge off southwestern Mindanao obviously is responsible for a high thermal conductivity which in turn could have enhanced heat flow (108.1 mW/m2) and methanogenesis (405 ppb). The heat flow of 103.0 mW/m2 at the deformation front of the Mindanao wedge and the high methane concentration of 5.555 ppb suggests tectonically induced fluid transport within the wedge. High methane concentrations between 8.044 and 49.006 ppb at the lower slope off Sulawesi and in the North Sulawesi Trench are accompanied by high heat flow values of up to 100.5 mW/m2. Heat flow is significantly lower upslope (31.3 mW/m2). This general heat flow distribution pattern is seen over a large portion of the accretionary wedge. The elevated heat flow values and high methane concentrations near the deformation front most likely result from heat transport by fluids squeezed out from vertically and laterally compacting sediments. The reduced heat flow towards the coast is compatible either with a cooling effect of slow subduction of the oceanic crust, or stacking of cool slabs of compacted sediments. A subduction of oceanic crust with a heat flow around 60 mW/m2 over a period of more than 3 million years would have produced the low heat flow values of the upper slope if the wedge consists of claystone with a low thermal conductivity (1.2 - 1.7 W/mK). Even in the low-heat flow area isolated fluid venting is possible. Lateral variations in the heat flow pattern (e.g. broadening of the anomalies in the west) may be due to different thermal regimes within the subducted crust.

Processed seismic data of Cruise BGR97

The 3rd cooperative BGR/SMNG Arctic cruise was designed to acquire new scietific data for a better understanding of temporal and spatial lithospheric variations during rifting and its influence on the tectonic and structural evolution of the continental crust of the Laptev Sea undergoing extension since at least the Early Tertiary, and for tackling open questions regarding the evolution of the submarine permafrost zone. Although conditions for seismic measurements were worse in 1997 than in 1993 and 1994, along 4,622 km of seismic traverses reflection seismic data and wide angle reflection/refraction data from 23 OBH-(ocean bottom hydrophone) stations were collected in the Laptev and East Siberian Sea. The most prominent rift basin is the Ust' Lena Rift, which is at least 300 km wide at latitude 75°N. The Cenozoic sedimentary cover exceeds 3 km everywhere, increasing up to 14 km at two locations. In the northern part of the shelf, the complex mainly N–S-trending Anisin Basin has a basin fill of up to 10 km thickness. The New Siberian Basin which is located in the northwestern part of the study area shows an up to 9 km thick graben fill. The Laptev Horst crust is locally subdivided into several tilted blocks by deep-reaching faults and there are several half grabens of smaller extent which divide the Laptev Horst into three parts: the North, the South and the East Laptev Horst. A major west dipping listric fault of at least 250 km length separates the Laptev Horst from the Ust' Lena Rift. Results from the seismological investigation indicate that recent extension is concentrated within the narrow rift basins of the eastern Laptev Sea. From wide-angle reflection/refraction seismic measurements the seismic velocities of the crustal layers were estimated along five profiles. The layers with velocities of up to 3.5 km/s apparently consist of predominantly Cenozoic sediments. The sedimentary section showing relatively high seismic velocities of 4.5 to 5.2 km/s might be interpreted as Late Paleozoic to Mesozoic deposits or overcompacted/cemented syn-rift deposits. In the eastern shelf area a layer beneath the acoustic basement was interpreted to represent Ordovician to Early Mesozoic carbonates. The lower crust in the area under study shows relatively uniform seismic velocities of about 6.0-6.8 km/s and the velocities estimated for the crust-mantle transition are in the range of 8.0 to 8.2 km/s. The origin of a several 100 m thick layer with a relative high velocity of 3 to 3.5 km/s directly beneath the seafloor was inferred as sub-sea permafrost.

Processed seismic data of Cruise Nares 2001

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.

Processed seismic data of Cruise SO49 1987

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.

Processed seismic data of Cruise MSM9/3

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.

CCE Status Report 2022

This report describes activities by the Coordination Centre for Effects (CCE) since the CCE was transferred from the Dutch National Institute for Public Health (RIVM) to the German Environment Agency (⁠ UBA ⁠) in 2018. The CCE is the programme centre for the International Cooperative Programme on Modelling and Mapping (ICP M&M) under the Working Group on Effects of the Convention of Long-range Transboundary Air Pollution (CLRTAP). The mandate of the CCE is to develop and update methodologies for assessing critical loads (CL), to compile data on CL and to generate maps of CL and their exceedances. Veröffentlicht in Texte | 135/2022.

Implementation and Development of GLI:X Green Logistics Indicators in South Africa

The GLI:X Green Logistics Indicators project has been established over several stages since 2016. Together with the province of Gauteng in South Africa, the project has succeeded in developing an indicator system for the measurability of green, socially responsible, and efficient freight logistics in the province in a cooperative dialog-oriented process. The aim of the present project was to build on the results and successes of the previous GLI:X projects and to further develop the GLI:X indicator system for other logistics-relevant cities and regions in South Africa in a participatory manner and to evaluate the possible applications on site. Veröffentlicht in Texte | 87/2022.

Critical Limits for Acidification and Nutrient Nitrogen

The International Cooperative Programme on Modelling and Mapping of Critical Levels and Loads and Air Pollution Effects, Risks and Trends (ICP Modelling and Mapping) develops and uses critical loads to recommend science-based emission reductions to policy makers within the ⁠ UN ⁠ Air Convention (CLRTAP). A critical load defines the deposition of a pollutant below which significant harmful effects on a sensitive ecosystem element are not expected to occur. The Simple Mass Balance (SMB) model is the most widely used steady-state model under the Air Convention to estimate critical loads for nutrient nitrogen (eutrophication) and sulphur together with nitrogen (acidification). Within the SMB model, so-called critical limits define chemical threshold values to prevent harmful effects in the ecosystem. In this report, the currently used critical limits for terrestrial ecosystems were reviewed. The project was motivated to ensure continuous uptake of scientific advances in the effects work. Experts of the National Focal Centres (NFC) and beyond were invited to comment and discuss preliminary results of the project during the ICP Modelling and Mapping Task Force meetings and a workshop. Results will be used by the Coordination Centre for Effects (CCE) to review the Mapping Manual for calculating critical loads. Veröffentlicht in Texte | 93/2024.

Green Markets: Investitionen in eine zukunftsfähige wirtschaftliche Entwicklung

Internationale UBA-Konferenz berät über nachhaltige Wohlstandsmodelle Konzepte für Grüne Zukunftsmärkte und eine ‘Green Economy‘ stehen im Mittelpunkt der internationalen UBA-Konferenz „Green Markets - World of Sustainable Products“ am 29. und 30.09.2011 in der Urania Berlin. ‘Green Economy‘ steht für ein energie- und ressourceneffizientes Wirtschaften. Damit soll weltweit eine nachhaltige Entwicklung initiiert werden, die Armut abbaut und ökologische Grenzen einhält. Einen wichtigen Schritt dazu bilden Investitionen in grüne Zukunftsmärkte. Die Tagung findet im Vorfeld der Rio+20-Konferenz im Juni 2012 statt, bei der die internationale Staatengemeinschaft über Wege zur ökologischen Modernisierung von Wirtschaft und Gesellschaft verhandelt. „Green Economy ist eine Schlüsselstrategie um Hunger und Armut in der Welt erfolgreich zu bekämpfen und die weltweite wirtschaftliche Entwicklung in den Grenzen der ökologischen Belastbarkeit unseres Planeten zu halten“, sagt UBA-Präsident Jochen Flasbarth. The pathway to a green economy provides industrial and developing countries with the prospect of ensuring prosperity without encroaching on the limits of the environment. In June 2012 – 20 years after the 1992 Rio Conference – the international community will gather at the United Nations Conference on Sustainable Development (UNCSD). At this so-called ‘Rio +20’ Conference the parties to the conference will discuss how the global community can move towards becoming an environmentally friendly, resource-saving and energy-efficient ‘green economy.’ Flasbarth comments, “Environmental protection may not be regarded as a niche policy. Development towards a green economy not only affects green sectors, but the very core of the economy“. Investment in green future markets lays the groundwork for a green economy. The Federal Ministry of Environment and the Federal Environment Agency have identified six green lead markets for Germany: environmentally friendly energy production, energy efficiency, material and resource efficiency, sustainable mobility, sustainable water management, and waste and recycling management. On a global scale these markets alone hold enormous potential valued at up to 3.1 trillion euros by 2020. The Roadmap to a Resource Efficient Europe, published on 20 September 2011, details the key components for a transition to an energy and resource-efficient economy in Europe. European Commissioner for Environment Janez Potočnik comments, “In a cooperative effort of Member States and interest groups in industry and civil society, we must create the conditions in which our economy can undergo fundamental changes in the coming years. We must send the right market signals, abolish subsidies harmful to the environment, and promote sustainable production and consumption.” Resource efficiency must be borne in mind in all policy-making areas- from waste management, research and innovation, to energy and transport. If nothing else, a true green economy will help to reduce absolute poverty in developing countries. The ⁠ UN ⁠ Environment Programme-led Green Economy Initiative of 2008 launched has made several proposals to this end. ⁠ UNECE ⁠ General Secretary Ján Kubiš comments, “Investment in natural capital—water, soil, ecosystems- not only makes an important contribution to global climate protection and the preservation of biodiversity, it also represents an investment in the economic viability of billions of people“. Dessau-Roßlau, 29.09.2011

Scenarios on the feasibility of emissions reductions consistent with 2°C stabilization

This report summarizes the results of the UFOPLAN project “Scenarios on the feasibility of emissions reduction scenarios consistent with 2°C stabilization” conducted by PIK and Ecofys. We use an integrated energy-economy-climate modeling system to examine how a further delay of cooperative action increases economic mitigation challenges. Veröffentlicht in Climate Change | 09/2014.

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