Fernandez-Lopez S.R.,Complutense University of Madrid |
Chong-Diaz G.B.,Northern University of Mexico
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2014
The first circum-Pacific record of the Bajocian dimorphic ammonite Strigoceras septicarinatum, from the Quebrada San Pedro area, Antofagasta, northern Chile, is described and illustrated. Morphological features of two specimens display macroconch and microconch characters of a single biospecies, usually assigned to separate morphospecies of the West Tethyan genera Strigoceras [macroconch] and Cadomoceras [microconch]. Preservational features of these two specimens, found in situ in the same stratigraphic level at the top of the Torcazas Formation, correspond to resedimented elements of the uppermost Bajocian Dimorphinites Biohorizon, contemporaneous with the sedimentary matrix. These specimens represent dimorphic shells produced by extremely scarce individuals inhabiting the Tarapaca Basin, without evidence of lasting biostratinomic modifications such as sorting by necroplanktic drift or biostratinomic encrusting. In the Tarapaca Basin, the distribution of ammonite shells was taphonomically and ecologically driven by regional changes of relative sea level. Taphonomic, paleoecological and paleobiogeographical observations in the areas of Quebrada San Pedro and Caracoles corroborate the development of an advanced-deepening phase, with episodes of sedimentary starvation, during the uppermost Bajocian, Parkinsoni Zone. This phase characterizes the last episode within a deepening half-cycle of a third order and the maximum deepening of a second-order, transgressive/regressive facies cycle, in the marine, back-arc Tarapaca Basin during the Bajocian-Bathonian interval. These paleontological and paleoenvironmental results represent new criteria to characterize the Dimorphinites Biohorizon in the Tarapaca Basin, allowing the identification the upper Bajocian Parkinsoni Zone in the East Pacific Subrealm, as well as chronocorrelation between the West Tethyan and East Pacific basins at the Bajocian/Bathonian boundary. © 2014 Elsevier B.V.
Herrera C.,Northern University of Mexico |
Custodio E.,University of Barcelona
Science of the Total Environment | Year: 2014
The island of Fuerteventura is the oldest of the Canary Islands' volcanic archipelago. It is constituted by volcanic submarine and subaerial activity and intrusive Miocene events, with some residual later volcanism and Quaternary volcanic deposits that have favored groundwater recharge. The climate is arid, with an average rainfall that barely attains 60mm/year in the coast and up to 200mm/year in the highlands. The aquifer recharge is small but significant; it is brackish due to large airborne atmospheric salinity, between 7 and 15gm-2year-1 of chloride deposition, and high evapo-concentration in the soil. The average recharge is estimated to be less than about 5mm/year at low altitude and up to 10mm/year in the highlands, and up to 20mm/year associated to recent lava fields. Hydrochemical and water isotopic studies, supported by water table data and well and borehole descriptions, contribute a preliminary conceptual model of groundwater flow and water origin in the Betancuria area, the central area of the island. In general, water from springs and shallow wells tends to be naturally brackish and of recent origin. Deep saline groundwater is found and is explained as remnants of very old marine water trapped in isolated features in the very low permeability intrusive rocks. Preliminary radiocarbon dating indicates that this deep groundwater has an apparent age of less than 5000years BP but it is the result of mixing recent water recharge with very old deep groundwater. Most of the groundwater flow occurs through the old raised volcanic shield of submarine and subaerial formations and later Miocene subaerial basalts. Groundwater transit time through the unsaturated zone is of a few decades, which allows the consideration of long-term quasi-steady state recharge. Transit times are up to a few centuries through the saturated old volcanics and up to several millennia in the intrusive formations, where isolated pockets of very old water may exist. © 2014 Elsevier B.V.
Guerrero V.M.,Autonomus Institute of Technology of Mexico |
Silva E.,Northern University of Mexico |
Gomez N.,Banco de Mexico
Journal of Forecasting | Year: 2014
We consider a forecasting problem that arises when an intervention is expected to occur on an economic system during the forecast horizon. The time series model employed is seen as a statistical device that serves to capture the empirical regularities of the observed data on the variables of the system without relying on a particular theoretical structure. Either the deterministic or the stochastic structure of a vector autoregressive error correction model of the system is assumed to be affected by the intervention. The information about the intervention effect is just provided by some linear restrictions imposed on the future values of the variables involved. Formulas for restricted forecasts with intervention effects and their mean squared errors are derived as a particular case of Catlin's static updating theorem. An empirical illustration uses Mexican macroeconomic data on five variables and the restricted forecasts consider targets for years 2011-2014. © 2013 John Wiley & Sons, Ltd.
Agency: Cordis | Branch: H2020 | Program: ERC-COG | Phase: ERC-CoG-2014 | Award Amount: 2.00M | Year: 2016
European incursions onto the narrow isthmian pass that divided and connected the Atlantic and Pacific oceans made it a strategic node of the Spanish Empire and a crucial site for early modern globalization. On the front lines of the convergence of four continents, Old Panama offers an unusual opportunity for examining the diverse, often asymmetrical impacts of cultural and commercial contacts. The role of Italian, Portuguese, British, Dutch, and French interests in the area, as well as an influx of African slaves and Asian merchandise, have left a unique material legacy that requires an integrated, interdisciplinary approach to its varied sources. Bones, teeth and artifacts on this artery of Empire offer the possibility of new insights into the cultural and biological impact of early globalization. They also invite an interdisciplinary approach to different groups tactics for survival, including possible dietary changes, and the pursuit of profit. Such strategies may have led the diverse peoples inhabiting this junction, from indigenous allies to African and Asian bandits to European corsairs, to develop and to favor local production and Pacific trade networks at the expense of commerce with the metropolis. This project applies historical, archaeological and archaeometric methodologies to evidence of encounters between peoples and goods from Europe, America, Africa and Asia that took place on the Isthmus of Panama during the sixteenth and seventeenth centuries. Forging an interdisciplinary approach to early globalization, it challenges both Euro-centric and Hispano-phobic interpretations of the impact of the conquest of America, traditionally seen as a demographic catastrophe that reached its nadir in the so-called seventeenth-century crisis. Rather than applying quantitative methods to incomplete source material, researchers will adopt a contextualized, inter-disciplinary, qualitative approach to diverse agents involved in cultural and commercial exchange.
Northern University of Mexico | Date: 2010-01-30
The present invention is related to providing a device for sampling, diluting and analyzing particles and substances normally located on surfaces, wherein said device comprises a collection system which, through a rotating collecting surface and a scraper gather the sample. The device also comprises a tank-like storage system to store the diluting solution and a dilution chamber that permits the sample to mix with the solution and be diluted. This mixture is subsequently placed in contact with a detection system which is capable of discerning the presence or not of the substance being sampled.