Nordische Geologie in nordischen Dichtungen

Ohne Zusammenfassung     

Post‐orogenic evolution of the southern Pyrenees: constraints from inverse thermo‐kinematic modelling of low‐temperature thermochronology data

The late‐stage evolution of the southern central Pyrenees has been well documented but controversies remain concerning potential Neogene acceleration of exhumation rates and the influence of tectonic and/or climatic processes. A popular model suggests that the Pyrenees and their southern foreland were buried below a thick succession of conglomerates during the Oligocene, when the basin was endorheic. However, both the amount of post‐orogenic fill and the timing of re‐excavation remain controversial. We address this question by revisiting extensive thermochronological datasets of the Axial Zone. We use an inverse approach that couples the thermo‐kinematic model Pecube and the Neighbourhood inversion algorithm to constrain the history of exhumation and topographic changes since 40 Ma. By comparison with independent geological data, we identified a most probable scenario involving rapid exhumation (>2.5 km Myr^?1) between 37 and 30 Ma followed by a strong decrease to very slow rates (0.02 km Myr^?1) that remain constant until the present. Therefore, the inversion does not require a previously inferred Pliocene acceleration in regional exhumation rates. A clear topographic signal emerges, however: the topography has to be infilled by conglomerates to an elevation of 2.6 km between 40 and 29 Ma and then to remain stable until ca. 9 Ma. We interpret the last stage of the topographic history as recording major incision of the southern Pyrenean wedge, due to the Ebro basin connection to the Mediterranean, well before previously suggested Messinian ages. These results thus demonstrate temporally varying controls of different processes on exhumation: rapid rock uplift in an active orogen during late Eocene, whereas base‐level changes in the foreland basin control the post‐orogenic evolution of topography and exhumation in the central Pyrenees. In contrast, climate changes appear to play a lesser role in the post‐orogenic topographic and erosional evolution of this mountain belt.     

The UNFCCC as a negotiation forum: towards common but more differentiated responsibilities

The principle of common but differentiated responsibilities and respective capabilities (CBDRC) captures the idea that it is the common responsibility of states to protect and restore the environment but that the levels and forms of states’ individual responsibilities may be differentiated according to their own national circumstances. This principle has shaped the evolution of the climate regime and has played an important role in promoting compromise and agreement. It is argued that some twenty years after the adoption of the United Nations Framework Convention on Climate Change (UNFCCC), the principle of CBDRC remains as relevant as ever. The practice of Parties under the regime and, most recently, the concerted efforts to shape and flesh out the meaning of the principle, underscore the central role that it plays. At the same time, the binary understanding of CBDRC in the Kyoto Protocol is being replaced with a more nuanced, multifaceted understanding. The evolving interpretation of CBDRC is considered, and its continued relevance as the nucleus of a global burden-sharing regime for addressing climate change is demonstrated.

Policy relevance

The development of a common understanding of the principle of CBDRC is essential for the burden sharing and responsibilities under a future climate agreement. The CBDRC principle captures the idea that it is the common responsibility of states to protect and restore the environment, but that the levels and forms of states’ individual responsibilities may be differentiated according to their own national circumstances. This article informs the international climate change negotiations by considering the development of the principle of CBDRC under the UNFCCC over time. It is concluded that, although there has been a significant shift in how the principle is understood, it remains crucial to the integrity and stability of the climate regime.     

Ethnic Place Identity Within A Parisian Neighborhood

The Goutte d'Or neighborhood of Paris has long been seen as an impoverished yet colorful quarter of the city. In recent years, it has also developed a reputation as a center for immigrants. Three populations now share the neighborhood: the European French, the Maghrebi immigrant population and their children, and the newest population of migrants from former Francophone colonies. This paper examines how the Goutte d'Or's social and ethnic identity is revealed in the built environment and in its social and economic activity. This neighborhood demonstrates how different communities and place identities coexist. It also shows how global networks of migration, exchange, and visits infuse local places. The Goutte d'Or distills many aspects of French immigrant identities, providing an example for increasing numbers of immigrant neighborhoods in France and across the world.     

Drivers of ecosystem and climate change in tropical West Africa over the past ∼540 000 years

A paucity of empirical non‐marine data means that uncertainty surrounds the impact of climate change on terrestrial ecosystems in tropical regions beyond the last glacial period. The sedimentary fill of the Bosumtwi impact crater (Ghana) provides the longest continuous Quaternary terrestrial archive of environmental change in West Africa, spanning the last ～1.08 million years. Here we explore the drivers of change in ecosystem and climate in tropical West Africa for the past ～540 000 years using pollen analysis and the nitrogen isotope composition of bulk organic matter preserved in sediments from Lake Bosumtwi. Variations in grass pollen abundance (0?99%) indicate transitions between grassland and forest. Coeval variations in the nitrogen isotopic composition of organic matter indicate that intervals of grassland expansion coincided with minimum lake levels and low regional moisture availability. The observed changes responded to orbitally paced global climate variations on both glacial–interglacial and shorter timescales. Importantly, the magnitude of ecosystem change revealed by our data exceeds that previously determined from marine records, demonstrating for the first time the high sensitivity of tropical lowland ecosystems to Quaternary climate change.

     

A Plan to Push Limits? Investigating the ecologically sustainable development dimensions of Melbourne's Central Region sustainable water strategy

Drawing upon theory from the field of urban political ecology, we analyse a major strategic water plan for Melbourne, Australia—the Sustainable water strategy for the Central Region, published in 2006. We assess the extent to which the strategy identified and addressed ecological sustainability in terms of: cultural frames; ecological context; social equity; and engagement processes. We identify that the strategy's framing of water was largely separate from its social and ecological context. This framing resulted in the importance of issues such as environmental flows, social equity and cultural values being diminished, thus avoiding the inevitable confrontation with environmental limits needed to ensure long-term ecological sustainability. Our analysis shows that the discursive dominance of economics limited the response to persuasive scientific arguments for greater ecological consideration in the strategy. Our findings suggest that broadening engagement with the diverse ways in which water is valued is likely to contribute to more equitable and ecologically sustainable water futures.     

Multi-risk governance for natural hazards in Naples and Guadeloupe

Technical and institutional capacities are strongly related and must be jointly developed to guarantee effective natural risk governance. Indeed, the available technical solutions and decision support tools influence the development of institutional frameworks and disaster policies. This paper analyses technical and institutional capacities, by providing a comparative evaluation of governance systems in Italy and France. The focus is on two case studies: Naples and Guadeloupe. Both areas are exposed to multiple hazards, including earthquakes, volcanic eruptions, landslides, floods, tsunamis, fires, cyclones, and marine inundations Cascade and conjoint effects such as seismic swarms triggered by volcanic activity have also been taken into account. The research design is based on a documentary analysis of laws and policy documents informed by semi-structured interviews and focus groups with stakeholders at the local level. This leads to the identification of three sets of governance characteristics that cover the key issues of: (1) stakeholders and governance level; (2) decision support tools and mitigation measures; and (3) stakeholder cooperation and communication. The results provide an overview of the similarities and differences as well as the strengths and weaknesses of the governance systems across risks. Both case studies have developed adequate decision support tools for most of the hazards of concern. Warning systems, and the assessment of hazards and exposure are the main strengths. While technical/scientific capacities are very well developed, the main weaknesses involve the interagency communication and cooperation, and the use and dissemination of scientific knowledge when developing policies and practices. The consequences for multi-risk governance are outlined in the discussion.     

Petrologic, isotopic, and radiometric age constraints on the origin and tectonic history of the Malino Metamorphic Complex, NW Sulawesi, Indonesia

The Malino Metamorphic Complex (MMC) is located at the western end of the north arm of Sulawesi. It consists of mica schists and gneisses (derived from proximal turbidite and granitoid protoliths), with intercalations of greenschist, amphibolite, marble, and quartzite, forming an E-W elongated dome-like structure bounded on all sides by faults. The age of the MMC is constrained between Devonian and Early Carboniferous. This Paleozoic age, the presence of Archean and Proterozoic inherited zircons, and the isotopic signature of the mica schists and gneisses indicate that the terrane was derived from the New Guinea-Australian margin of Gondwana. Similarities with basement rocks in the Bird’s Head suggests a common origin. Greenschists forming a discontinuous selvage (metamorphic carapace) around the complex were derived from adjacent autochthonous Paleogene formations. The rocks of the MMC show a Barrovian-type progression from greenschist through epidote-amphibolite to amphibolite facies. P–T estimations suggest a depth of burial of up to 27–30 km. K/Ar and 40Ar/39Ar cooling ages of 23–11 Ma, and a 7 Ma age for unconformably overlying volcanic rocks, indicate that the complex was exhumed during the Miocene. Two tectonic scenarios are considered: 1. the continental fragment docked with Sulawesi during the Mesozoic and was exhumed as a metamorphic core complex during the Miocene; 2. it was subducted beneath the north arm during the late Oligocene and then rapidly returned back to the surface.