(Table 1) Radiolarian accumulation rates and geochemistry of ODP Site 184-1143

Late Miocene-Recent micropaleontological and geochemical records from Ocean Drilling Program (ODP) Site 1143 in the southern South China Sea (SCS) indicate that increase and decrease in abundance of siliceous plankton may be controlled mainly by the input of nutrients derived from land and provided by upwelling. A high export production event - a "biogenic bloom" event - occurred in the southern SCS between 12 and 6 Ma. During this period, high ratios of smectite/(illite + chlorite), smectite/quartz and Al/K indicate a high weathering intensity of the Asian continent, possibly due to the intensification of the East Asian Summer Monsoon (EASM), which may have increased the net flux of nutrients to the ocean, both directly through terrestrial input and indirectly through upwelling activity. A drop in Ba/Ti, Al/Ti and Ca/Ti values around 6 Ma may indicate a lowering of productivity, possibly due to the large consumption of sea surface nutrients by the "biogenic bloom". Alternatively, it may indicate a shift in terrigenous input source area. At about 5.4 Ma, a decrease in weathering intensity, as indicated by a sudden decrease in the values of smectite/(illite + chlorite), smectite/quartz and Al/K, might have led to a sudden decrease of terrestrial nutrient input to the SCS. We suggest that the biogenic bloom ended when nutrients in surface waters were exhausted, because of a decrease in supply as well as a decrease in upwelling intensity due to weakening of the EASM. As a result, radiolarians were absent in the studied area between ~6 and 3.2 Ma. At ~3.2 Ma, radiolarians began to recover, possibly because the start of Northern Hemispheric glaciation and the rapid uplift of the Tibet Plateau led to intensification of the East Asian monsoon. After the Mid-Pleistocene Climate Transition at 0.9 Ma, the abundance and mass accumulation rates of radiolarians increased, probably as a result of increased upwelling activity driven by the increasing intensity of the summer monsoon.

Granulometry, mineralogy and geochemistry of ODP Holes 184-1147A and 184-1148A, South China Sea

Green clay layers are reported from the Pliocene-Holocene intervals in five of the six sites drilled in the South China Sea (SCS) during Leg 184. Centimeter-scale discrete, discontinuous, and bioturbated layers, constituted by stiff and porous green clays, were observed, sometimes associated with iron sulfides and pyrite. Detailed mineralogical and geochemical analyses indicate that they differentiate from the host sediments in their higher content of iron, smectite, and mixed-layered clays and lower amounts of calcite, authigenic phosphorus, quartz, and organic matter. Although no glauconite was observed, the mineralogy and geochemistry of green clay layers, along with their geometrical relation to background sediments, suggest that they most likely represent the result of the first steps of glauconitization. Correlation between green layers and volcanic ash layers was suggested for green laminae observed elsewhere in Pacific sediments but was not confirmed at SCS sites. Statistical analysis of the temporal distribution of green layers in the records of the last million years suggests that green clay layers have become more frequent since 600 ka. Only at Site 1148 does the green layer record show a statistically significant cyclicity which may be related to orbital eccentricity. A possible influence of sea level variations, related both to climatic changes and tectonism, is postulated.

Stable isotopes of benthic foraminifera from Site ODP 184-1146

We generated a high resolution (~8 ky) benthic record from a West Pacific marginal basin to investigate the detailed structure and spectral characteristics of deep water isotope fluctuations during the middle Miocene. The benthic record from ODP Site 1146 allows unprecedented resolution of the structure of the middle Miocene delta13C excursion, as well as tighter control on the chronology of climatic events. Spectral analysis of the variance in the delta18O and delta13C records from ODP Site 1146 reveals spectral power concentrated in the eccentricity band (400-, ~100-ky) over the time interval between 13 and 17 Ma. The amplitude evolution in the 400-ky band is strikingly similar to that of the long eccentricity in Laskar's solution. There is an abrupt switch to the obliquity band in the delta18O record at -14.9 Ma, suggesting a shift in the ocean/climate response to orbital forcing (from low latitude eccentricity to high latitude obliquity forcing). The obliquity signal is pervasive in the delta18O record until -13.9 Ma, when a sharp increase in delta18O values indicates a major climatic transition. Comparison of delta18O and delta13C profiles from DSDP Site 588 (SW Pacific Ocean), ODP Site 761 (E Indian Ocean) and ODP Site 1146 (South China Sea) reveals significantly cooler deep water in the NE Indian Ocean throughout the middle Miocene and a restricted deep water exchange between the Pacific Ocean and Indian Ocean.

Strength of the Iberian intraplate lithosphere: Cenozoic deformations and seismicity

Previous studies about the strength of the lithosphere in the Iberia centre fail to resolve the depth of earthquakes because of the rheological uncertainties. Therefore, new contributions are considered (the crustal structure from a density model) and several parameters (tectonic regime, mantle rheology, strain rate) are checked in this paper to properly examine the role of lithospheric strength in the intraplate seismicity and the Cenozoic evolution. The strength distribution with depth, the integrated strength, the effective elastic thickness and the seismogenic thickness have been calculated by a finite element modelling of the lithosphere across the Central System mountain range and the bordering Duero and Madrid sedimentary basins. Only a dry mantle under strike-slip/extension and a strain rate of 10-15 s-1, or under extension and 10-16 s-1, causes a strong lithosphere. The integrated strength and the elastic thickness are lower in the mountain chain than in the basins. These anisotropies have been maintained since the Cenozoic and determine the mountain uplift and the biharmonic folding of the Iberian lithosphere during the Alpine deformations. The seismogenic thickness bounds the seismic activity in the upper–middle crust, and the decreasing crustal strength from the Duero Basin towards the Madrid Basin is related to a parallel increase in Plio–Quaternary deformations and seismicity. However, elasto–plastic modelling shows that current African–Eurasian convergence is resolved elastically or ductilely, which accounts for the low seismicity recorded in this region.

On the microstructure, growth pattern and original porosity of belemnite rostra: insights from calcitic Jurassic belemnites

Calcitic belemnite rostra are usually employed to perform paleoenvironmental studies based on geochemical data. However, several questions, such as their original porosity and microstructure, remain open, despite they are essential to make accurate interpretations based on geochemical analyses.This paper revisits and enlightens some of these questions. Petrographic data demonstrate that calcite crystals of the rostrum solidum of belemnites grow from spherulites that successively develop along the apical line, resulting in a “regular spherulithic prismatic” microstructure. Radially arranged calcite crystals emerge and diverge from the spherulites: towards the apex, crystals grow until a new spherulite is formed; towards the external walls of the rostrum, the crystals become progressively bigger and prismatic. Adjacent crystals slightly vary in their c-axis orientation, resulting in undulose extinction. Concentric growth layering develops at different scales and is superimposed and traversed by a radial pattern, which results in the micro-fibrous texture that is observed in the calcite crystals in the rostra.Petrographic data demonstrate that single calcite crystals in the rostra have a composite nature, which strongly suggests that the belemnite rostra were originally porous. Single crystals consistently comprise two distinct zones or sectors in optical continuity: 1) the inner zone is fluorescent, has relatively low optical relief under transmitted light (TL) microscopy, a dark-grey color under backscatter electron microscopy (BSEM), a commonly triangular shape, a “patchy” appearance and relatively high Mg and Na contents; 2) the outer sector is non-fluorescent, has relatively high optical relief under TL, a light-grey color under BSEM and low Mg and Na contents. The inner and fluorescent sectors are interpreted to have formed first as a product of biologically controlled mineralization during belemnite skeletal growth and the non-fluorescent outer sectors as overgrowths of the former, filling the intra- and inter-crystalline porosity. This question has important implications for making paleoenvironmental and/or paleoclimatic interpretations based on geochemical analyses of belemnite rostra.Finally, the petrographic features of composite calcite crystals in the rostra also suggest the non-classical crystallization of belemnite rostra, as previously suggested by other authors.

Resolución 184 del 19 de noviembre de 2102: Por la cual se resuelve una revocatoria directa

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Reducing the global burden of depression : population level analysis of intervention cost-effectiveness in 14 world regions

International evidence on the cost and effects of interventions for reducing the global burden of depression remain scarce. Aims: To estimate the population-level cost-effectiveness of evidence-based depression interventions and their contribution towards reducing current burden. Method: Primary-care-based depression interventions were modelled at the level of whole populations in 14 epidemiological subregions of the world. Total population-level costs (in international dollars or I$) and effectiveness (disability adjusted life years (DALYs) averted) were combined to form average and incremental cost-effectiveness ratios. Results: Evaluated interventions have the potential to reduce the current burden of depression by 10–30%. Pharmacotherapy with older antidepressant drugs, with or without proactive collaborative care, are currently more cost-effective strategies than those using newer antidepressants, particularly in lower-income subregions. Conclusions: Even in resource-poor regions, each DALYaverted by efficient depression treatments in primary care costs less than 1 year of average per capita income, making such interventions a cost-effective use of health resources. However, current levels of burden can only be reduced significantlyif there is a substantialincrease substantial increase intreatment coverage.

Making Money from Monsters

It seems Australia is the place to be at the moment when it comes to making and creating horror films. Mark David Ryan explains how you can get involved in this boom industry. If you’re a writer with a passion for scary movies, a wordsmith who watches the occasional horror flick and writing your own has crossed your mind, or a writer who terrifies readers with an interest in screenwriting, then there has never been a better time to write Aussie horror flicks. This article introduces the horror genre’s core characteristics, issues to consider when crafting a horror flick, and provides tips for getting scripts into the hands of producers.