Crust-Mantle Velocities in the Iberian Peninsula and Tectonic Implications of the Seismicity in this Area     

Gonzalo Payo 《Geophysical Journal International》1972,30(1):85-99

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Stock Evaluation of Three Littoral Echinoid Species on the Catalan Coast North-Western Mediterranean   总被引：2，自引：0，他引：2  

Cruz  Palacín  Xavier  Turon  Manuel  Ballesteros  Gonzalo  Giribet Salvador  López 《Marine Ecology》1998,19(3):163-177

Abstract. We estimated the abundances of the three common littoral echinoid species Paracentrotus lividus, Arbacia lixula and Sphaerechinus granularis in a littoral zone between 0 and 10m depth on the Catalan shores NE Spain. Densities of each species were estimated from a total number of 11 571× 1 m² sampling units deployed at 152 sites along the 13 zones into which the coast was divided. The surface area available in each of these zones was estimated at the scale of the sampling unit 1 m² taking into account the fractal dimension of the shore. The stocks individuals > 2cm test diameter of these species for the whole Catalan shore ≅ 300 km, straight-line distance were estimated to be about 279.1 × 10⁶ individuals for P. lividus , 28.9 × 10⁶ individuals for A. lixula and 10.9 × 10⁶ individuals for S. granularis. These sea-urchins are key species in the regulation of algal communities and some of them P. lividus. S. granularis are of commercial interest. This information will provide a tool for the future monitoring and management of this resource, which now faces diverse pressures of human origin.  相似文献   

The Upper Jurassic (Kimmeridgian) fluvial–aeolian systems of the southern Neuquén Basin, Argentina     

Gonzalo D. Veiga  Luis A. Spalletti 《Gondwana Research》2007,11(3):286-302

The Kimmeridgian Quebrada del Sapo Formation in the southernmost Neuquén Basin in Argentina represents a succession up to 40 m thick of coarse- to fine-grained fluvial deposits overlain by aeolian deposits. These fluvial–aeolian deposits reflect a significant palaeogeographic change in the basin and are related to a major, tectonically enhanced, relative sea-level fall. The fluvial section is dominated by braided-channel, fine-grained ephemeral, and sheetflood deposits. Aeolian facies are dominated by dune deposits, with minor sandsheet and interdune units. Changes in the nature of both fluvial and aeolian sedimentation within the studied area suggest a regional variability of accommodation/sediment supply conditions. The regional changes of the aeolian succession likely reflect different relative positions within a major erg. In the upwind margin of the erg, a shallow water table promoted water-lain sedimentation in interdune areas, whereas in the central parts of the erg, dry sediment accumulation took place above the regional water-table level. The vertical transition observed in the Quebrada del Sapo Formation, from fluvial to aeolian deposits, may be the result of a local climatic change to drier conditions due to the development of a climatic barrier imposed by growth of a magmatic arc to the west. Alternatively, the vertical transition could be related to a lowering of the water table associated with the compartmentalization of the basin during a period of low sea level.  相似文献   

A Note on the Ground Particle Motion of Near Earthquakes     

Gonzalo Payo  Manuel Prensa 《Geophysical Journal International》1969,18(1):129-137

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Aeolian/fluvial interactions and high-resolution sequence stratigraphy of a non-marine lowstand wedge: the Avilé Member of the Agrio Formation (Lower Cretaceous), central Neuquén Basin, Argentina     

Gonzalo D. Veiga†  Luis A. Spalletti†‡  Stephen Flint 《Sedimentology》2002,49(5):1001-1019

Abstract Accumulation within the unconformity‐based Hauterivian Avilé Sandstone of the Neuquén Basin, Argentina, was characterized by a close interaction between fluvial and aeolian processes developed after a major relative sea‐level drop that almost completely desiccated the entire basin and juxtaposed these non‐marine deposits on shallow‐ and deep‐marine facies. Aeolian deposits within the Avilé Member include dune (A1) and sand sheet (A2) units that characterize the lower part of the unit. Fluvial deposits comprise distal flood units (F1) interbedded with aeolian dune deposits in the middle part of the succession, and low‐ (F2) and high‐sinuosity (F3) channels associated with floodplain deposits (F4) towards the top. The internal characteristics of the aeolian system indicate that its accumulation was strongly controlled by water‐table dynamics, with the development of multiple horizontal deflation super surfaces that truncate dune deposits and form the basal boundary of flood deposits and sand sheet units. A long‐term wetting‐upward trend is recorded throughout the entire unit, with an increase in fluvial activity towards the top and the development of a more permanent fluvial system overlying a major erosion surface interpreted as a sequence boundary. The upward increase in water‐table influence might be related to relative sea‐level rise, which controlled the position of the water table and allowed the accumulation of tabular aeolian units bounded by horizontal deflation surfaces. This high‐frequency, eustatically driven process acted together with a long‐term climatic change towards wetter conditions.  相似文献   

Analysis and Classification of Natural Rock Textures based on New Transform-based Features     

Rodrigo Lobos  Jorge F. Silva  Julián M. Ortiz  Gonzalo Díaz  Alvaro Egaña 《Mathematical Geosciences》2016,48(7):835-870

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Coastal inundation under concurrent mean and extreme sea-level rise in Coral Gables,Florida, USA     

Alarcon  Vladimir J.  Linhoss  Anna C.  Kelble  Christopher R.  Mickle  Paul F.  Sanchez-Banda  Gonzalo F.  Mardonez-Meza  Fernando E.  Bishop  Joseph  Ashby  Steven L. 《Natural Hazards》2022,111(3):2933-2962

Natural Hazards - Southeast Florida (SF) is among the most vulnerable regions to sea-level rise in the United States of America. The consequences associated with sea-level rise (SLR) are already...  相似文献   

Combining point and regular lattice data in geostatistical interpolation     

Jorge Jódar  Gonzalo Sapriza  Christian Herrera  Luis Javier Lambán  Agustín Medina 《Journal of Geographical Systems》2015,17(3):275-296

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Parameters of Higuchi’s method to characterize primary waves in some seismograms from the Mexican subduction zone     

Gonzalo Gálvez-Coyt  Alejandro Mu?oz-Diosdado  José A. Peralta  José A. Balderas-López  Fernando Angulo-Brown 《Acta Geophysica》2012,60(3):910-927

Higuchi’s method is a procedure that, if applied appropriately, can determine in a reliable way the fractal dimension D of time series; this fractal dimension permits to characterize the degree of correlation of the series. However, when analyzing some time series with Higuchi’s method, there are oscillations at the right-hand side of the graph, which can cause a mistaken determination of the fractal dimension. In this work, an appropriate explanation is given to this type of behaviour. Using the seismogram as a time series and the properties of the P and S waves, it is possible to use the properties of Higuchi’s method to previously detect the arrival of the earthquake shacking stage, some seconds in advance, approximately 30–35 s in the case of Mexico City. Thus, we propose the Higuchi’s method to characterize and detect the P waves in order to estimate the strength of the forthcoming S waves.  相似文献   

Variogram-Based Descriptors for Comparison and Classification of Rock Texture Images     

Díaz  Gonzalo F.  Ortiz  Julián M.  Silva  Jorge F.  Lobos  Rodrigo A.  Egaña  Álvaro F. 《Mathematical Geosciences》2020,52(4):451-476

Mathematical Geosciences - Rock characterization is typically performed by geologists in mining companies and involves the analysis of several meters of drill-hole samples to describe distinctive...  相似文献