Drainage of a deep magma reservoir near Mayotte inferred from seismicity and deformation

The dynamics of magma deep in the Earth’s crust are difficult to capture by geophysical monitoring. Since May 2018, a seismically quiet area offshore of Mayotte in the western Indian Ocean has been affected by complex seismic activity, including long-duration, very-long-period signals detected globally. Global Navigation Satellite System stations on Mayotte have also recorded a large surface deflation offshore. Here we analyse regional and global seismic and deformation data to provide a one-year-long detailed picture of a deep, rare magmatic process. We identify about 7,000 volcano-tectonic earthquakes and 407 very-long-period seismic signals. Early earthquakes migrated upward in response to a magmatic dyke propagating from Moho depth to the surface, whereas later events marked the progressive failure of the roof of a magma reservoir, triggering its resonance. An analysis of the very-long-period seismicity and deformation suggests that at least 1.3 km3 of magma drained from a reservoir of 10 to 15 km diameter at 25 to 35 km depth. We demonstrate that such deep offshore magmatic activity can be captured without any on-site monitoring

Mitochondrial DNA diversity and population structure of humpback whales from their wintering areas in the Indian and South Atlantic Oceans (Wintering Regions A,B, C and X). Scientific Committee document SC/56/SH3, International Whaling Commission, July 2004, Sorrento, Italy

Humpback whales in the Southern Hemisphere are separated by the International Whaling Commission (IWC) into seven wintering Regions (A-G) based on tropical distribution. To better evaluate the significance of these stock subdivisions, an analysis of mtDNA was conducted for the eastern and western South Atlantic (Regions A and B), the southwestern Indian Ocean (Region C) and the northern Indian Ocean (Region X). A total of 1,416 individual whales representing eleven sampling sites within the four wintering Regions were sequenced for a portion of the mtDNA control region. A hierarchical analysis of molecular variance (AMOVA) using FST and FST supported the division of wintering Regions based on IWC designated boundaries of A, B, C, and X. Pairwise comparisons further confirmed the A, B and C divisions, although varying degrees of heterogeneity (particularly molecular distances) were detected for proposed sub-divisions within Regions B and C. Overall, this large-scale mtDNA analysis for humpback whales in the Indian and South Atlantic Oceans supports wintering Region designations by the IWC. However, additional analyses and consideration of biological parameters such as gene flow are needed so that ‘within-region’ genetic analyses can help evaluate population structure and recovery in a management context

Twenty-first-century trade governance: findings from the Commonwealth countries

© 2019 Western Economic Association International This paper focuses on twenty-first-century-trade governance patterns within the Commonwealth (CW) countries. It uses an augmented gravity model to examine the role of governance in influencing trade and investment flows, and whether enhanced trade governance within the CW countries could potentially foster trade gains, on a both intra- and extra-CW basis. Results show a 10% reduction in the costs incurred for a good to exit a country can increase intra-CW exports by 5%. Second, contract enforcement is more efficient among CW members, and requires 20% less time compared to the world average. Third, every 1 percentage point improvement in government effectiveness triggers an increase in exports from CW, at 3.4%, compared to the rest of the world, at 2.4%. Finally, trade between CW members is three times higher when they belong to an existing regional trade agreement (F10, 011, F13)

Population Structure of Humpback Whales from Their Breeding Grounds in the South Atlantic and Indian Oceans

Although humpback whales are among the best-studied of the large whales, population boundaries in the Southern Hemisphere (SH) have remained largely untested. We assess population structure of SH humpback whales using 1,527 samples collected from whales at fourteen sampling sites within the Southwestern and Southeastern Atlantic, the Southwestern Indian Ocean, and Northern Indian Ocean (Breeding Stocks A, B, C and X, respectively). Evaluation of mtDNA population structure and migration rates was carried out under different statistical frameworks. Using all genetic evidence, the results suggest significant degrees of population structure between all ocean basins, with the Southwestern and Northern Indian Ocean most differentiated from each other. Effective migration rates were highest between the Southeastern Atlantic and the Southwestern Indian Ocean, followed by rates within the Southeastern Atlantic, and the lowest between the Southwestern and Northern Indian Ocean. At finer scales, very low gene flow was detected between the two neighbouring sub-regions in the Southeastern Atlantic, compared to high gene flow for whales within the Southwestern Indian Ocean. Our genetic results support the current management designations proposed by the International Whaling Commission of Breeding Stocks A, B, C, and X as four strongly structured populations. The population structure patterns found in this study are likely to have been influenced by a combination of long-term maternally directed fidelity of migratory destinations, along with other ecological and oceanographic features in the region

Governance, Democracy and Poverty Reduction: Lessons Drawn from Household Surveys in Sub-Saharan Africa and Latin America

Public statistics face quite a challenge when it comes to measuring new dimensions of development (institutions, governance, and social and political participation). To take up this challenge, modules on "Governance, Democracy and Multiple Dimensions of Poverty" have been appended to household surveys by National Statistics Institutes in twelve African and Latin American developing countries. This paper presents the issues addressed and the methodological lessons learnt along with a selection of findings to illustrate this innovative approach and demonstrate its analytic potential. We investigate, for instance, the population's support for democratic principles, the respect for civil and political rights and the trust in the political class; the 'need for the State', particularly of the poorest; the extent of petty corruption; the reliability of expert surveys on governance; the perception of decentralization policies at local level; the level and vitality of social and political participation, etc. The conclusive appraisal made opens up prospects for the national statistical information systems in the developing countries. The measurement and tracking of this new set of objective and subjective public policy monitoring indicators would benefit from being made systematic. Copyright 2007 The Authors. Journal compilation (c) 2007 International Statistical Institute.