Spanish Participation in the Millimeter Array

The Spanish participation as an Associate Member in the Millimeter Array (MMA) project - led by the U.S. National Radio Astronomy Observatory (NRAO) - has been recently proposed to the Spanish Science and Technology Bureau (OCYT). This request to the Spanish Government is based on two key factors: (1) The high scientific interest and support of the Spanish scientific community, for whom major new fields of research--inaccessible with other instruments--will become available. (2) An industrial return that will clearly benefit Spanish companies developing cutting-edge technology and providing them with a high international profile. This revised version was published online in July 2006 with corrections to the Cover Date.     

Earth observations for sustainable development goals monitoring based on essential variables and driver-pressure-state-impact-response indicators

ABSTRACT

In recent years, researchers of different communities have increased their efforts in formalizing a set of measurements regularly collected for analysing changes in Drivers, States, Impacts and Responses of a given discipline. In some cases, different actors have converged in a minimum set of Essential Variables (EVs), such as for Climate, Biodiversity or Oceans. The definition of such EVs is an ongoing evolution and in extension (e.g. EVs for water) although some communities have not even started (e.g. agriculture and energy). This paper characterizes the Earth Observation (EO) networks and creates a graph representation of their relations. Secondly, this graph is enriched with the EVs produced by each network creating a knowledge base. Finally, an effort has been done to identify links between EVs and Sustainable Development Goals (SDG) indicators in a way that they indirectly connect the EO. An analysis to detect gaps in EO variables due to a lack of observational networks is performed. Several suggestions for improving SDG indicators framework by considering EVs are exposed, as well as proposing new necessary EVs and suggesting new EO based indicators. The complete graph is available in the ENEON website (http://www.eneon.net/graph-ev-sdg/).     

Towards integrated essential variables for sustainability

ABSTRACT

Measuring the achievement of a sustainable development requires the integration of various data sets and disciplines describing bio-physical and socio-economic conditions. These data allow characterizing any location on Earth, assessing the status of the environment at various scales (e.g. national, regional, global), understanding interactions between different systems (e.g. atmosphere, hydrosphere, biosphere, geosphere), and modeling future changes. The Group on Earth Observations (GEO) was established in 2005 in response to the need for coordinated, comprehensive, and sustained observations related to the state of the Earth. GEO’s global engagement priorities include supporting the UN 2030 Agenda for Sustainable Development, the Paris Agreement on Climate, and the Sendai Framework for Disaster Risk Reduction. A proposition is made for generalizing and integrating the concept of EVs across the Societal Benefit Areas of GEO and across the border between Socio-Economic and Earth systems EVs. The contributions of the European Union projects ConnectinGEO and GEOEssential in the evaluation of existing EV classes are introduced. Finally, the main aim of the 10 papers of the special issue is shortly presented and mapped according to the proposed typology of SBA-related EV classes.     

Hydrogeological interactions between fault zones and alluvial aquifers in regional flow systems

The hydrological influence of fault zones in tectonic areas is usually difficult to depict from field data. Numerical simulation allows representation of such flow systems and an estimation of flow lines and rates. This paper reports on simulations of the groundwater flow in a range‐and‐basin area affected by a regional fault zone, which may drain or recharge an overlaying alluvial aquifer. Different hydraulic conductivity values for the range rocks, the fault‐zone, and the sedimentary infill of the basin are considered, as well as different fault‐zone widths and boundary conditions. Results show that upward and downward fluxes develop in the upper part of the fault zone, controlled by the action of the alluvial aquifer, influencing the recharge of the sedimentary basin. This paper shows the hydrological efficiency of fault zones as preferential flow; it also analyses the constraints that determine groundwater recharge to the surrounding basins. These results contribute to the understanding of hydrogeological dynamics in tectonic areas. Copyright © 2008 John Wiley & Sons, Ltd.     

Change Estimates by Map Comparison: A Method to Reduce Erroneous Changes Due to Positional Error

A common method to assess land use/cover change (LUCC) is the comparison of digital maps of an area within a geographic information system (GIS). However, positional errors of the maps involved in the comparison affect this assessment and much of the change shown by means of this comparison may be an artifact due to these errors. This note presents a simple method to improve change estimates by detecting and correcting erroneous changes resulting from positional errors. It allows an important reduction of error in change area estimates and is likely to be useful in LUCC assessment studies.     

Tectono-stratigraphic evolution of an inverted extensional basin: the Cameros Basin (north of Spain)

The Cameros Basin is a part of the Mesozoic Iberian Rift. It is an extensional basin formed during the late Jurassic and early Cretaceous, in the Mesozoic Iberian Rift context, and it was inverted in the Cenozoic as a result of the Alpine contraction. This work aims to reconstruct the tectono-stratigraphic evolution of the basin during the Mesozoic, using new and revised field, geophysical and subsurface data. The construction of a basin-wide balanced section with partial restorations herein offers new insights into the geometry of the syn-rift deposits. Field data, seismic lines and oil well data were used to identify the main structures of the basin and the basin-forming mechanisms. Mapping and cross-sectional data indicate the marked thickness variation of the depositional sequences across the basin, suggesting that the extension of the depositional area varied during the syn-rift stage and that the depocentres migrated towards the north. From field observation and seismic line interpretation, an onlap of the depositional sequences to the north, over the marine Jurassic substratum, can be deduced. In the last few decades, the structure and geometry of the basin have been strongly debated. The structure and geometry of the basin infill reconstructed herein strongly support the interpretation of the Cameros Basin as an extensional-ramp synclinal basin formed on a blind south-dipping extensional ramp. The gradual hanging-wall displacement to the south shifted the depocentres to the north over time, thus increasing the basin in size northwards, with onlap geometry on the pre-rift substratum. The basin was inverted by means of a main thrust located in a detachment located in the Upper Triassic beds (Keuper), which branched in depth with the Mesozoic extensional fault flat. The reconstruction of the tectono-stratigraphic evolution of the Cameros Basin proposed herein represents a synthesis and an integration of previous studies of the structure and geometry of the basin. This study can be used as the basis for future basin-scale research and for modelling the ancient petroleum system of the basin.     

Analysis of size effects on the geomechanical parameters of intact granite samples under unconfined conditions

A total of 28 uniaxial compressive strength tests were performed on cylindrical Blanco Mera granite samples with diameters ranging between 14 and 100 mm, with results indicating that this granite undergoes a significant reverse size effect: the UCS increases as sample diameter increases up to 54 mm, but thereafter decreases. It was also found that the results tend to be more scattered for smaller sample diameters. We also found an apparent correlation between Young’s modulus and sample diameter. It was not possible to draw any clear conclusions regarding the variability in Poisson’s ratio with sample size. With respect to crack initiation and crack damage stresses, the behaviour of the tested samples also indicates a reverse effect. This research would suggest that the traditionally assumed decrease in strength as sample size increases does not hold for granite samples with diameters below 54 mm.     

Causes of variation in crystal morphology in metamorphogenic pyrite deposits of the Cameros Basin (N Spain)

The low‐grade metasediments of the Cameros Basin, northern Spain, host a number of deposits of spectacular quality pyrite mineralization. These formed during regional metamorphism and the pyrite crystals exhibit a wide range of morphologies. On the basis of pyrite crystal habit, the deposits can be classified into two groups: Group I comprises deposits with cubic, elongated or platy crystals; Group II comprises deposits characterized by pyritohedra and cubo‐pyritohedra with striated faces, along with blocky crystals and fine‐grained aggregates. Group I deposits are formed in sequences dominated by meandriform fluviatile sediments, while Group II is hosted by deltaic plain and lacustrine metasediments. Temperature differences between deposits and As content are possible causes of the different pyrite morphologies in the deposits, but no significant variation exists between the two groups for either factor. Comparison with experimentally grown pyrite crystals suggests that Group I deposits have morphologies indicative of lower degrees of pyrite supersaturation than pyrite crystals in Group II deposits. The sedimentary facies hosting Group II deposits provides a greater availability of sedimentary sulphur (pyrite and sulphates). Moreover, reactions involving sulphate during metamorphism may have modified fluid chemistry, which would also act to produce higher degrees of pyrite saturation in fluids derived from the sulphate‐rich deltaic plain and lacustrine metasediments hosting the Group II deposits. This hypothesis is confirmed by sulphur isotope data on the pyrites, which show a larger component of³⁴S‐enriched sulphate‐derived sulphur in these deposits. Copyright © 2001 John Wiley & Sons, Ltd.