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201.
Mixed siliciclastic‐carbonate deep‐marine systems (mixed systems) are less documented in the geological record than pure siliciclastic systems. The similarities and differences between these systems are, therefore, poorly understood. A well‐exposed Late Cretaceous mixed system on the northern side of the Eastern Greater Caucasus, Azerbaijan, provides an opportunity to study the interaction between contemporaneous siliciclastic and carbonate deep‐marine deposition. Facies analysis reveals a Cenomanian–early Turonian siliciclastic submarine channel complex that abruptly transitions into a Mid Turonian–Maastrichtian mixed lobe‐dominated succession. The channels are entrenched in lows on the palaeo‐seafloor but are absent 10 km towards the west where an Early Cretaceous submarine landslide complex acted as a topographic barrier to deposition. By the Campanian, this topography was largely healed allowing extensive deposition of the mixed lobe‐dominated succession. Evidence for irregular bathymetry is recorded by opposing palaeoflow indicators and frequent submarine landslides. The overall sequence is interpreted to represent the abrupt transition from Cenomanian–early Turonian siliciclastic progradation to c. Mid Turonian retrogradation, followed by a gradual return to progradation in the Santonian–Maastrichtian. The siliciclastic systems periodically punctuate a more widely extensive calcareous system from the Mid Turonian onwards, resulting in a mixed deep‐marine system. Mixed lobes differ from their siliciclastic counterparts in that they contain both siliciclastic and calcareous depositional elements making determining distal and proximal environments challenging using conventional terminology and complicate palaeogeographic interpretations. Modulation and remobilisation also occur between the two contemporaneous systems making stacking patterns difficult to decipher. The results provide insight into the behaviour of multiple contemporaneous deep‐marine fans, an aspect that is challenging to decipher in non‐mixed systems. The study area is comparable in terms of facies, architectures and the presence of widespread instability to offshore The Gambia, NW Africa, and could form a suitable analogue for mixed deep‐marine systems observed elsewhere.  相似文献   
202.
Total ozone data series for 1957–82 at ten locations were subjected to Maximum Entropy Spectral Analysis. Besides the annual, semi-annual, and quasi-biennial oscillations, peaks were noticed at 3.5–4, 6–7, and 10–11 years. For Arosa, Switzerland, for a longer period (1932–71), an additional peak was indicated at about 16 years.  相似文献   
203.
This article is a case study of the Mitigation Action Plans and Scenarios programme (MAPS) which worked in climate change mitigation and development policy-making spaces in Brazil, Chile, Colombia, Peru and South Africa from 2010–2015. The MAPS programme was focused on achieving change in the commitment of southern decision makers to mitigate against climate change through government-mandated, stakeholder processes which generated evidence making a case for a low carbon transition. The article draws on reflective materials generated in the last year of the project. The value of MAPS was found in the well-tested data and evidence-driven scenario building; locally specific and country-driven processes; a culture of knowledge sharing through facilitated communities of practice; the role of professional facilitation in process design and in conducting stakeholder processes; shared experiences of working in the south, and particularly with cultural differences and conflict; and new ways of working south–south with each other, and with donors. These MAPS programme experiences stood in contrast to previous north–south knowledge sharing involvements. Theoretically, the article asks whether MAPS represents southern theory-making (after Connell, 2007). It concludes that through the action-oriented, facilitated co-production way of working on climate change in the south, MAPS represents an understanding of southern theory that challenges the orthodoxy of global knowledge production. MAPS emphasizes the need for theorizing in, and of, the south, and connecting policy and practices.

Key policy insights

  • Climate change mitigation work in the south faces poorly resourced, fragmented, under-capacitated governance structures, often in conflicted settings.

  • Given conflicted settings, skilled facilitation is an integral part of knowledge-making processes.

  • Strong local communities of practice, who undertake learning-by-doing and are connected to ‘stubborn’ development realities, are also key to knowledge-making.

  • Intentional co-production of data and evidence enable peer-to-peer learning and the trust-building which is vital to strong communities of practice.

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