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.
Between 08.11.1999 and 02.12.1999 the active convergent margin off Costa Rica was investigated using the S/V Professor Polshkov. The cruise had three scientific targets. Several seismic profiles in the dip-direction of the subduction zone were acquired to map the general variability of the accretionary wedge. Near the Jaco Scarp, a dense net of seismic profiles using a smaller seismic source should deliver information about the amount of gas hydrates within the shallow sub-surface. In an area of this wedge south of the Quepos Plateau densely spaced seismic lines were measured to prepare an ODP campaign (which was finished in 2011 as IODP Expedition 334).
The structure and tectonics of the Pacific margin of Costa Rica were studied by multichannel seismic measurements in parallel with gravity measurements and swathmapping from the Cocos Ridge to Nicoya Peninsula during R/V SONNE cruise SO81 legs 1 and 2 from 18th August to 15th September 1992. In addition geological sampling has been carried out. Dominant structural feature is the buried Costa Rica Terrrane (CRT), a complex and segmented, wedge-shaped unit characterized by relative high seismic velocities of 4 km/s. The thickness of this several tens of kilometres wide zone varies between 0.5 and 3 s (twt). The CRT forms the backstop against which the sediments of the subducting Cocos plate accrete resulting in accumulation of sedimentary mass beneath and in front of the CRT, as well as in simultaneous uplift and fracturing of the CRT. It appears that the distinct CRT is affected locally by raft tectonics, i.e. a form of thin-skinned extension by normal faulting from gravity sliding over a non-stretched oceanic crust. A unit is recognizable between the base of the CRT and the surface of the subducting oceanic crust on most of the seismic lines. This unit is thought to consist mostly of ductile pelagic to hemipelagic shales. Some segment boundaries of the CRT are associated with morphological furrows, 5 to 10 km wide and up to 30 km long running across the slope. We feel that the data acquired during SONNE cruise SO81, and the preliminary results at hand have already improved our knowledge on the geological processes of active continental margins. We are convinced that plausible concepts for the origin of tsunamis and asperities can be developed on the basis of the data collected during SONNE cruises SO81 and SO76. The research of both SONNE cruises are a contribution to the International Decade of Natural Desaster Reduction (IPNDR).
Am 8. Oktober 2015 schlossen sich die zwanzig am stärksten durch den Klimawandel bedrohten Staaten zur Gruppe der V20 zusammen. Die Finanzminister der Staaten Afghanistan, Äthiopien, Bangladesch, Barbados, Bhutan, Costa Rica, Ghana, Kenia, Kiribati, Madagaskar, die Malediven, Nepal, Osttimor, die Philippinen, Ruanda, St. Lucia, Tansania, Tuvalu, Vanuatu und Vietnam gründeten ihre Allianz in Lima, Peru als Gegengewicht zur G20-Gruppe der führenden Industrie- und Schwellenländer. Die V20 beschlossen die Einrichtung eines Versicherungsmechanismus gegen extreme Wetterphänomene und Naturkatastrophen, der aus privaten und öffentlichen Quellen finanziert werden soll. Für ihr Eröffnungstreffen wählten die V20 die peruanische Hauptstadt Lima, wo in dieser Woche auch die Jahrestreffen der Weltbank und des Internationalen Währungsfonds (IWF) stattfanden. In einer Erklärung hieß es, die V20 seien „Heimat von fast 700 Millionen Menschen, und wir sind vereint in unserer geteilten Verletzlichkeit und Gefährdung durch den Klimawandel.“
Ein Übergang zu einer nachhaltigen Entwicklung und Netto-Null-Treibhausgasemissionen auf allen Ebenen der Gesellschaft ist der Schlüssel zum Erreichen der im Übereinkommen von Paris (ÜvP) festgelegten Temperaturziele und der globalen Ziele für nachhaltige Entwicklung (engl. Sustainable Development Goals, SDGs) der Agenda 2030. Das Umweltbundesamt (UBA) hat UNEP DTU Partnership in Zusammenarbeit mit Perspectives Climate Research und First Climate mit der Durchführung dieses Forschungsprojektes beauftragt, um zu untersuchen, wie Kohlenstoffmarktansätze unter Artikel 6 des ÜvP zu der von diesen globalen Abkommen geforderten transformativen Wirkung beitragen können. Das Projekt zielt darauf ab, Erkenntnisse und Empfehlungen für die Gestaltung und Umsetzung von Artikel 6-Regeln und -Aktivitäten zur Förderung des transformativen Wandels durch Kohlenstoffmärkte zu generieren. Auf der Grundlage von Erkenntnissen aus einer Literaturrecherche und Interviews schlagen die Autoren eine Definition von transformativem Wandel vor: â€ÌEin grundlegender, nachhaltiger Wandel eines Systems, der etablierte kohlenstoffintensive Praktiken beendet und zu einer emissionsfreien Gesellschaft beiträgt, im Einklang mit dem Ziel des Pariser Abkommens, die globale Erwärmung auf 1,5-2˚C zu begrenzen, und den Nachhaltigkeitszielen der Vereinten Nationen", mit vier Merkmalen, die für die Ziele von Artikel 6 besonders relevant sind, nämlich "Digitalisierung", "Privatsektor und Regierungen", "Kohlenstoffpreisgestaltung" und "dynamische Baselines". Auf der Grundlage der Artikel 6-Verhandlungen bis zur COP26 in Glasgow und eines Überblicks über Artikel 6-Pilotprojekte werden konzeptionelle Optionen für Artikel 6-Aktivitäten zur Förderung eines transformativen Wandels vorgestellt. Eine Anreizstruktur für Kohlenstoffmärkte zur Förderung höherer Ambitionen in den national festgelegten Beiträgen (engl. Nationally Determined Contributions, NDCs) und der transformativen Wirkung wird vorgestellt. Erkenntnisse aus einer vergleichenden Fallstudienanalyse verschiedener NDCs und Sektoren in Costa Rica, Marokko und Pakistan zeigen, wie transformative Auswirkungen auf der Ebene der Artikel-6-Aktivitäten konzipiert und bewertet werden können. Die Ergebnisse werden genutzt, um Implikationen für die Gestaltung von Artikel 6 zu identifizieren, damit Aktivitäten ihre transformative Wirkung verstärken. Beispielsweise können höhere Preise für international übertragene Minderungsergebnisse (engl. internationally transferred mitigation outcomes, ITMOs) mit Transformationswirkung den politischen Willen in den Gastgeberländern stärken, Möglichkeiten zur umfassenden Minderung zu ergreifen und gleichzeitig kosteneffiziente Emissionsminderungen mit eigenen Mitteln zu erreichen. Die wichtigsten Schlussfolgerungen und Empfehlungen lauten, dass Kernprinzipien des Kohlenstoffmarktes wie Zusätzlichkeit und stringente Baselines neu interpretiert werden können, um einen transformativen Wandel zu fördern, der auf das globale Temperaturziel von 1,5 ˚C ausgerichtet ist. Quelle: Forschungsbericht
Das Projekt "eco:fibr" wird vom Umweltbundesamt gefördert und von Leibniz Universität Hannover, Institut für Technische Chemie durchgeführt. Ecofibr hat ein umweltfreundliches Verfahren entwickelt, um aus den bislang ungenutzten Resten der Ananaspflanze Zellstoff zu extrahieren. Die Pflanzenreste stellen in Anbauländern ein ökologisches und finanzielles Problem für die Farmer da. Alleine in Costa Rica fallen jährlich mehr als 4,5 Millionen Tonnen davon an und eine Entsorgung kostet bis zu 2.000 Euro pro Hektar. In Kooperation mit Ananasfarmen in Costa Rica sowie dem Institut für technische Chemie der Leibniz Universität hat das Team einen Prozess entwickelt, um aus diesen Resten Zellstoff für papierproduzierende Unternehmen herzustellen. Damit kann diesen eine umweltfreundliche Alternative zu Holz-Zellstoff angeboten werden, welcher teilweise immer noch aus Primärwäldern bezogen und in ressourcenintensiven Verfahren hergestellt wird. Ananaspflanzenreste eignen sich für das Vorhaben besonders gut, u.a. aufgrund des hohen Cellulosegehaltes und des großen weltweiten Vorkommens. Gegenüber anderen, alternativen Rohstoffen für die Zellstoffproduktion (wie Gras oder Bagasse) zeichnet sich ecofibr-Zellstoff durch den ressourcenschonenden Prozess, eine große saisonunabhängige Verfügbarkeit sowie die gleichzeitig gute industrielle Verarbeitbarkeit aus. Letzteres wurde bereits durch Analysen von papierproduzierenden Unternehmen und potentiellen Kunden bestätigt, mit welchen bereits Absichtserklärungen vorliegen. Bei dem innovativen Prozess handelt es sich um ein abgewandeltes Sodaverfahren, dessen Patentierung beabsichtigt wird und zurzeit in Bearbeitung ist. Diverse Abschlussarbeiten von Teammitgliedern haben sich bereits intensiv mit dem Thema Zellstoffcharakterisierung, Identifikation von Produktmöglichkeiten, Ökobilanz sowie Identifikation von Nebenströmen und Abwässern beschäftigt. Ecofibr möchte mit diesem Vorhaben zu einem effizienten und nachhaltigen Umgang mit Ressourcen beitragen. Die Vision von ecofibr ist es, Zellstoff Primärrohstoffen durch ein Produkt aus Pflanzenresten zu substituiere- (Text abgebrochen)
Das Projekt "Sub project: Participation in a site survey cruise off Costa Rica on RV Ewing" wird vom Umweltbundesamt gefördert und von Universität Bremen, Fachbereich 05: Geowissenschaften, Fachgebiet Meerestechnik - Sensorik durchgeführt. Im vorgeschlagenen Forschungsprogramm sollen konventionelle Wärmestromdichtemessungen vor Costa Rica ergänzt werden durch Messungen des Temperaturgradienten über einen Tiefenbereich von 6 m. Dieses Gebiet seewärts des Grabens und nördlich der RSB-Linie ist durch einen extrem niedrigen Wärmestrom gekennzeichnet, dessen Ursache bislang nicht bekannt ist. Diese Wärmestromdichtemessungen zusammen mit seismischen Vermessungen werden im April/Mai 2001 vom amerikanischen Forschungsschiff RV Ewing aus durchgeführt werden. Prof. Dr. A. Fisher (Univ. California at Santa Cruz) hat ein Mitglied meiner Arbeitsgruppe eingeladen, an den Wärmestromdichtemessungen teilzunehmen und die Messungen durch unsere spezielle Sonde zu ergänzen... Ein Schwerpunkt der Messungen wird in Bereichen mit Wassertiefen größer als 4.000 m liegen, da dort die konventionelle Wärmestromsonde wegen der Drucklimitierung der Elektronikdruckbehälter nicht mehr eingesetzt werden kann. Der andere Schwerpunkt liegt auf den Messungen langer Temperaturprofile im Graben, um dort evtl. vorhandene nichtstationäre Einflüsse durch hohe Sedimentationsraten, Variationen der Bodenwassertemperatur oder durch advektiven Transport aufzudecken. Die Ergebnisse werden mit den von Langseth und Silver (1996) publizierten Ergebnissen wie auch den Daten von Leg 170 (Silver et al., 2000; Ruppel and Kinoshita 2000) verknüpft werden. Sie liefern damit ein Bild der regionalen Verteilung des Wärmestromes und zusätzliche site survey Informationen für Leg 203.
Das Projekt "Sub project: Site survey data evaluation IODP Proposal 633" wird vom Umweltbundesamt gefördert und von Helmholtz-Zentrum für Ozeanforschung Kiel (GEOMAR) durchgeführt. IODP drilling proposal (Costa Rica Mud Mounds) aims to enhance the general understanding of complex forearc dewatering processes of the erosive subduction system off Costa Rica and Nicaragua. Scientific evaluation recently resulted in a high ranking of the drilling proposal. Major sites of dewatering planned for drilling are mounds, related to mud diapirism/volcanism and precipitation of authigenic carbonates, and large-scale slides related to the subduction of seamounts. New pre-site survey seismic data was collected during a cruise of R/V Marcus Langseth in 2008 at the proposed sites of Mound Culebra and Mounds 11&12. These new data - together with the reprocessed pre-existing geophysical data - were submitted to the IODP safety panel for a final decision and scheduling of the R/V Joides Resolution leg. The new data are of exceptionally high quality and allow a detailed analysis of the processes that control fluid migration in the Costa Rican margin. Therefore we propose to (1) investigate the role of the acoustic basement for the fluid ascent, (2) understand the effect of mud volcanism on the gas hydrate system and the interactions between gas hydrate formation and dissociation with the fluid ascent from the deep sources, and (3) to invert the seismic data for gas and gas hydrate concentrations. The extension of the project will provide a wealth of geological information and further promote the drilling proposal.
Das Projekt "Übernahme von Arachis pintoi als Bodendecker- und Weidepflanze in Costa Rica" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Fakultät III Agrarwissenschaften I, Institut für Pflanzenproduktion und Agrarökologie in den Tropen und Subtropen, Fachgebiet Biodiversität und Landrehabilitation in den Tropen und Subtropen durchgeführt. Scarcity of land resources and decreasing prices for agricultural products in Costa Rica lead to an overuse of agricultural resources. There is an urgent need for production systems that increase income but conserve natural resources at the same time. The forage legume Arachis pintoi appears to provide advantages in pastures and as a cover crop. It has an excellent forage value and reduces erosion due to its stoloniferous growth. Through its N fixing capabilities soil quality is enhanced. Its weed depressing effects in coffee and citrus plantations is well known. Adoption of A. pintoi by farmers has been observed but occurs only very slowly. In this project factors promoting or impeding adoption of this innovation are identified and evaluated quantitatively. Socio-economic data from farm and household levels are analysed as well as infrastructural, institutional and other data from the regional level. Of particular importance are the access of farmers to training, credit, seed and other input. Furthermore, the adoption potential of A. pintoi in Costa Rica will be determined. Based on the results of this study recommendations for measures to improve diffusion of this legume will be elaborated.
Das Projekt "Sub project: Seafloor deformation and point convergence of and between two CORK monuments off Nicoya Peninsula, Costa Rica" wird vom Umweltbundesamt gefördert und von Universität Bremen, Fachbereich 05: Geowissenschaften, Fachgebiet Meerestechnik - Sensorik durchgeführt. The overall goal of the proposed project is to monitor seafloor deformation (vertical movement and tilt) of the seafloor at the Middle American subduction zone off Nicoya Peninsula, Costa Rica. Two CORKs, installed during Leg 205 will be used as seafloor geodetic monuments and equipped with high resolution state-of-the-art point position monitoring devices. The devices are (1) a water level sensor, i.e. a pressure meter, that provides 0.7mm resolution at ambient pressure of the vertical position with respect to mean sea level and (2) self-leveling biaxial tiltmeters that measure the angle displacements in two perpendicular horizontal directions with a very high resolution of Snrad. To control environmental conditions high resolution temperature loggers will be included in the monitoring system. The measurements will run over approximately two years at sampling intervals of some minutes to provide a comprehensive multi-scale data set of CORK motion. Local influences on CORK motion from e.g. formation pressure changes and differential motion between both CORKs will be studied in detail. The determined values of CORK motion will be compared and linked to the global plate tectonic movement pattern, measured on land at the same time by other groups. One of the locations (Site 1253) is located in the trench about 200m seaward of the deformation front whereas the other location (Site 1255) is only 600m away from 1253 and located 400m arcward of the deformation front. By monitoring pressures and tilt at both sites we will be able to measure relative as well as absolute deformation. It is planned to install the system in the fall of 2007 with a ROV/submersible and recover it about two years later.