Structural controls on Quaternary deepwater sedimentation, mud diapirism, and hydrocarbon distribution within the actively evolving Columbus foreland basin, eastern offshore Trinidad     

Emilio Garciacaro  Alejandro Escalona  Paul Mann 《Marine and Petroleum Geology》2011,28(1):149-176

Eastward migration of the Caribbean plate relative to the South American plate has caused lithospheric loading along the northern margin of South America, which is recorded by an 1100-km-long foreland basin which is oldest in the west (Maracaibo basin, 65-55 Ma) and youngest in the east (Columbus basin, eastern offshore Trinidad, 15-0 Ma). The Orinoco River has been the primary source of sediment for the basin since early Miocene. We have integrated approximately 775 km of deep-penetration 2D seismic lines acquired in the area of eastern offshore Trinidad as part of the 2004 “Broadband Ocean-Land Investigations of Venezuela and the Antilles arc Region” (BOLIVAR) project, 8000 km² of shallow industry 3D seismic data, and published industry well data from offshore eastern Trinidad. Active mud diapirism in the Columbus basin is widespread and is related to overthrusting and tectono-sedimentary loading of upper Miocene-lower Pliocene age mud. Analysis of the shallow 3D seismic data reveals the presence of extensive gravity-flow depositional elements on the Columbus basin slope and the deepwater area. These stacked gravity-flow deposits are characterized by mass-transport deposits at the base, turbidite frontal-splay deposits, leveed-channel deposits, and capped by fine-grained condensed-section deposits. Exploration targets in the deepwater area are located towards the center of the Columbus basin, where northeast-trending fault-propagation folds are important Plio-Pleistocene trap-forming elements. Deep basin wells drilled in recent years have proven that turbidites were transported into the deepwater Columbus basin during the Plio-Pleistocene. Analysis of these well results suggests that a deeper oil charge is present within the deepwater Columbus basin area. The primary uncertainty for this variable hydrocarbon system is whether fault or diapiric pathways connect or divert the petroleum charge at depth with shallower reservoir rocks.  相似文献   

Magnetic reorientation induced by pressure solution: A potential mechanism for orogenic-scale remagnetizations     

Belén Oliva-Urcia  Emilio L. Pueyo  Juan C. Larrasoaña 《Earth and Planetary Science Letters》2008,265(3-4):525-534

New paleomagnetic analyses of Triassic, Cretaceous and Eocene strata in the south-central Pyrenees show evidence for a widespread remagnetization, located along the southern border of the Axial Zone, the Internal Sierras, and the northern part of the Jaca-Pamplona basin. This remagnetization, always reversed in polarity, was acquired after an extensive period of Late Eocene–Early Oligocene folding and tilting in the area, and affects limestones, sandstones, marls and red beds. In addition, a characteristic prefolding component was identified in 30% of Upper Cretaceous and Triassic red beds. These results, together with a revaluation of previously published paleomagnetic data from the central Pyrenees, indicate that the spatial distribution of the postfolding remagnetization coincides with that of a domain of pressure solution cleavage. A relationship between the intensity of the remagnetization and the characteristic (prefolding component) with respect to the density of cleavage surfaces, leads us to propose a mechanism for the remagnetization related to the development of pressure solution cleavage that is framed within the tectonic evolution of the central Pyrenees. Partial dissolution of rock under tectonic compression leads to the liberation and subsequent accumulation of insoluble minerals in cleavage planes. Magnetic grains are part of the relatively insoluble residue, and they reorient in the presence of the ambient field after they are freed during dissolution of the rock matrix. Chemical reequilibrium (dissolution and/or neoformation of magnetic carriers) during this process cannot be excluded. The remagnetization mechanism we propose can help to explain widespread remagnetizations in low to moderately deformed rocks without the need of large-scale migration of orogenic fluids.  相似文献   

Monitoring of mercury and other metals mobility by sequential fractionation in soils nearby an abandoned chlor-alkali plant in Managua (Nicaragua)     

Rodolfo Fernández-Martínez  Belén Gómez-Mancebo  Emilio J. Peña  Pilar Galán  Akito Matsuyama  Fernando García  Isabel Rucandio 《Environmental Earth Sciences》2016,75(6):538

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Horizon Restoration by Best Fitting of Finite Elements and Rotation Constraints: Sensitivity to the Mesh Geometry and Pin-Element Location     

María José Ramón  José Luis Briz  Emilio L. Pueyo  Oscar Fernández 《Mathematical Geosciences》2016,48(4):419-437

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Erratum to: Application of extreme learning machine for estimation of wind speed distribution     

Shahaboddin Shamshirband  Kasra Mohammadi  Chong Wen Tong  Dalibor Petković  Emilio Porcu  Ali Mostafaeipour  Sudheer Ch  Ahmad Sedaghat 《Climate Dynamics》2016,46(5-6):2025-2025

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New precipitation and temperature grids for northern Patagonia: Advances in relation to global climate grids          下载免费PDF全文

Emilio Bianchi  Ricardo Villalba  Maximiliano Viale  Fleur Couvreux  Rocio Marticorena 《Acta Meteorologica Sinica》2016,30(1):38-52

Climate data of mean monthly temperature and total monthly precipitation compiled from different sources in northern Patagonia were interpolated to 20-km resolution grids over the period 1997–2010. This northern Patagonian climate grid (NPCG) improves upon previous gridded products in terms of its spatial resolution and number of contributing stations, since it incorporates 218 and 114 precipitation and temperature records, respectively. A geostatistical method using surface elevation from a Digital Elevation Model (DEM) as the ancillary variable was used to interpolate station data into even spaced points. The maps provided by NPCG are consistent with the broad spatial and temporal patterns of the northern Patagonian climate, showing a comprehensive representation of the latitudinal and altitudinal gradients in temperature and precipitation, as well as their related patterns of seasonality and continentality. We compared the performance of NPCG and various other datasets available to the climate community for northern Patagonia. The grids used for the comparison included those of the Global Precipitation Climatology Project, ERAInterim, Climate Research Unit (University of East Anglia), and University of Delaware. Based on three statistics that quantitatively assess the spatial coherence of gridded data against available observations (bias, MAE, and RMSE), NPCG outperforms other global grids. NPCG represents a useful tool for understanding climate variability in northern Patagonia and a valuable input for regional models of hydrological and ecological processes. Its resolution is optimal for validating data from the general circulation models and working with raster data derived from remote sensing, such as vegetation indices.  相似文献   

Nuovo accelerometro a massima per la componente orizzontale     

Perri  Emilio 《Pure and Applied Geophysics》1940,2(1):229-229

Pure and Applied Geophysics -  相似文献   

Discontinuita', densita' e compressibilita' cubica nell'interno della Terra     

Prof. Emilio Oddone 《Pure and Applied Geophysics》1939,1(1):157-174

Riassunto Il tracciamento delle odografe sismiche ha fatto cambiare le nostre conoscenze intorno alla distribuzione della densità nell'interno della terra. Prima erano valide le formole di Légendre, di Roche e di Helmert dall'andamento continuo, adesso la più accreditata relazione tra densità e profondità è quella discontinua del professor K. E. Bullen. Questa nota si inizia coll'esposizione di queste discontinuità, poi vuol cercarne la causa. Ammette che l'andamento continuo si riferisca agli albori della formazione della terra e man mano il forte aumento di densità nel nucleo centrale sia stato dovuto ad una sedimentazione del mezzo disperso pesante in seno al primordiale continuo.Un secondo aumento più modesto si è verificato nei primi mille km. dalla superficie, specie intorno ai 481 km. di profondità, dovuto ad azioni plutoniche. I due aumenti essendosi prodotti a spese del guscio intermedio, un paragone tra le tre prime distribuzioni e l'attuale permette di impostare un bilancio tra le masse guadagnate dal nucleo —rispettivamente dagli strati superficiali — e la massa perduta da detto guscio intermedio (mantello). Queste quantità si bilanciano nel sistema di E. Roche che pertanto rischia la ventura di essere chiamato ilmilliarum aureum nella storia della terra.Sono anche dati i coefficienti di compressibilità cubica, alle diverse pressioni, delle incognite sostanze costituenti l'interno del Globo.La ricerca in parallelo a quella delle densità, è una specie di presagio sulla natura di quelle sostanze espresso in base alle dette costanti fisiche.In complesso la terra sarebbe prevalentemente formata da due classi di meteoriti: la sideritica nel nucleo e la ferrosporica nel mantello. In ciascun riparto la sostanza sarebbe pressoché omogenea, il relativo aumento di densità e la relativa diminuzione di compressibilità essendo dovuti al peso degli strati sopraincombenti.  相似文献   

Un modello inteso a mostrare la propagazione entro il Globo delle onde sismiche longitudinali     

Emilio Oddone 《Pure and Applied Geophysics》1939,1(1):73-79

Riassunto Il modello che proponiamo consta di un bacino circolare le cui dimensioni stanno in dato rapporto con quelle della sezione diametrale terrestre. Nell'acqua che contiene, uno scotimento presso al suo bordo produce determinate onde idrodinamiche. Opportuni rialzi del fondo del bacino fanno variare da sito a sito la profondità dell'acqua e quindi la velocità dell'onda. La nota delinea quale sagoma debba assumere il fondo del bacino perchè le velocità dell'onda liquida risultino proporzionali a quelle delle onde sismiche longitudinali nell'interno della terra. Il modello altera il fenomeno fisico, ma raggiunge lo scopo di dare un'immagine del fronte d'onda che ha le identiche caratteristiche del fronte sismico. Si può infatti seguire ad occhio il transito della lente onde gravitazionali liquide nel bacino, mentre in qualsiasi modello non sarebbe possibile seguire la propagazione delle rapidissime onde elastiche.  相似文献   

Analysis of the ferromagnetic contribution to the susceptibility by low field and high field methods in sedimentary rocks of the Southern Pyrenees and Northern Ebro foreland basin (Spain)     

Óscar Pueyo Anchuela  Antonio M. Casas‐Sainz  Emilio L. Pueyo  Andrés Pocoví Juan  Andrés Gil Imaz 《地学学报》2013,25(4):307-314

Magnetic susceptibility in rocks is the sum of the contributions of different magnetic particles (paramagnetic, diamagnetic and ferromagnetic s.l.). These contributions can be measured at variable temperatures or at variable fields (hysteresis loops). Both are time‐consuming techniques that cannot be routinely used in magnetic fabrics analysis. In this study, we propose a simplified method to determine the ferro‐ and paramagnetic contributions to the susceptibility, based on the discrete measurement of susceptibility at two different fields (near 0 and 2.5 T). The results obtained in samples from the Southern Pyrenees and Ebro Basin indicate that the ferromagnetic contribution vary considerably within homogeneous susceptibility values and within the expected range of paramagnetic values. Standard bulk susceptibilities higher than 200 10^?6 SI contribute significantly to the ferromagnetic fraction (>50% on average).  相似文献