Consulta: subjectFacets:"Gravity"
Registros recuperados: 15
Data/hora: 10/06/2024 06:30:20

FUJI Dome: A large detachment fault near 64 degrees E on the very slow-spreading southwest Indian Ridge
Provedor de dados: 5
Autores: Searle, Rc; Cannat, M; Fujioka, K; Mevel, C; Fujimoto, H; Bralee, A; Parson, L.
A continuous, domed detachment surface ( FUJI Dome) has been imaged on the very slow-spreading southwest Indian Ridge using deep-towed side-scan sonar, and has been investigated by manned submersible and sea-surface geophysics. The Dome is morphologically similar to other oceanic detachments, core complexes or mega-mullions. In addition to bathymetric mullions observed in ship-borne bathymetry, finer scale spreading-parallel striations were imaged with the side scan. On the detachment surface, metabasalt crops out near the termination, probably as part of a thin fault sliver. Gabbro and troctolite probably crop out near the summit of the dome. The rest of the detachment surface is covered with sediment and rubble which is basaltic except for a single...
Tipo: Text
Palavras-chave: Southwest Indian Ridge; Detachment; Submersible; Magnetic; Gravity; Marine geology and geophysics : midocean ridge processes; Marine geology and geophysics :; Seafloor morphology and bottom photography.
Ano: 2003
URL: https://archimer.ifremer.fr/doc/00226/33706/32124.pdf

Active faulting and deep crustal structure of the Eastern Sicily Margin
Provedor de dados: 5
Autores: Dellong, David.
In the Ionian Sea (central Mediterranean) the slow convergence between Africa and Eurasia results in the formation of a narrow subduction zone. The nature of the crust of the subducting plate remains debated and could represent the last remnants of the Neo-Tethys ocean. The origin of the Ionian basin is also under discussion, especially concerning the rifting mechanisms as the Malta Escarpment could represent a remnant of this opening. This subduction retreats toward the south-east (motion occurring since the last 35 Ma) but is confined to the narrow Ionian basin. A major lateral slab tear fault is required to accommodate the slab rollback.This fault is thought to propagate along the eastern Sicily margin but its precise location remains controversial.This...
Tipo: Text
Palavras-chave: Méditerranée; Ionien; Calabre; Géodynamique; Marge; Faille de déchirure lithosphérique; Sismicité; Sismique; Grand-angle; Bathymétrie; Gravimétrie; Modélisation; Mediterranean; Ionian; Calabria; Geodynamic; Subduction; Margin; STEP fault; Wide-angle seismic; Seismicity; Bathymetry; Gravity; Modelling.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00499/61026/64430.pdf

New structural and geochemical observations from the Pacific-Antarctic Ridge between 52°45'S and 41°15'S
Provedor de dados: 5
Autores: Klingelhoefer, Frauke; Ondreas, Helene; Briais, A; Hamelin, C; Dosso, Laure.
We investigated the morphology and structure of the Pacific-Antarctic Ridge between 52 degrees 45'S and 41 degrees 15'S during the Pacantarctic2 cruise using multibeam echosounder together with gravity measurements and dredges. Analysis of the bathymetric, gravity and geochemical data reveal three ridge segments separated by overlapping spreading centers south of the Menard transform fault (MTF) and five segments north of it. Calculation of the cross-sectional area allows quantification of the variation in size of the axial bathymetric high. Together with the calculation of the mantle Bouguer anomaly, these data provide information about variations in the temperature of the underlying mantle or in crustal thickness. Areas with hotter mantle are found north...
Tipo: Text
Palavras-chave: Mantle Bouguer anomaly; Temperature variations; Geochemistry; Gravity; Bathymetry; Ridge segment.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-2108.pdf

Evolution Géodynamique du domaine Ouest-offshore de la Nouvelle-Calédonie et de ses extensions vers la Nouvelle-Zélande
Provedor de dados: 5
Autores: Collot, Julien.
The southwest Pacific results from the fragmentation of Gondwanaland since the Cretaceous time.  The purpose of the current PhD work is to deepen our understanding of the history of the New Caledonia and Fairway basins, located west of New Caledonia, in order to better constrain the geodynamical evolution of the SW Pacific from Cretaceous to Oligocene. The analysis of new geophysical data has led to distinguish 3 main phases of this fragmentation:  1 Mid Cretaceous formation of the Fairway-Aotea Basin in a continental intra-arc position. The formation of this basin reflects the initial stage of continental fragmentation of the Eastern Gondwana margin. The causes of this fragmentation are to be searched for in a major change of the dynamics of the...
Tipo: Text
Palavras-chave: Subduction; Obduction; Norfolk; Lord Howe; Gondwana; Taranaki; New Caledonia; Fairway; Aotea; Magnetic; Gravity; Seismic; Subduction; Obduction; Norfolk; Lord Howe; Gondwana; Taranaki; Nouvelle Calédonie; Fairway; Aotea; Magnétisme; Gravimétrie; Sismique.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/these-6520.pdf

Crustal structure of the NW Moroccan margin from deep seismic data (SISMAR Cruise)
Provedor de dados: 5
Autores: Jaffal, Mohammed; Klingelhoefer, Frauke; Matias, Luis; Teixeira, Fernando; Amrhar, Mostafa.
During the SISMAR cruise (spring 2001), new deep seismic data were acquired on the Atlantic Moroccan margin. The purpose of the present work is to analyse and to interpret a part of the data consisting of four wide-angle seismic profiles (4, 5, 8 and 10) recorded offshore El Jadida. Lines 4 and 5, perpendicular to the margin, show a crustal thickness of 35 km under the western Moroccan Meseta which thins progressively seaward where it reaches a minimum thickness of 10 km. The calculated velocity models show that this crust consists of two crustal layers overlain by a sedimentary cover corresponding to the post-Paleozoic sediments, characterised by a low velocity. The detailed shallow structure is obtained primarily from multichannel seismic data. Half...
Tipo: Text
Palavras-chave: Morocco; Passive margin; Gravity; OBS; Velocity model; Deep seismic.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6588.pdf

Crustal structure and continent-ocean boundary along the Galicia continental margin (NW Iberia): insights from combined gravity and seismic interpretation
Provedor de dados: 5
Autores: Druet, M.; Munoz-martin, A.; Granja-bruna, J. L.; Carbo-gorosabel, A.; Acosta, J.; Llanes, P.; Ercilla, G.
The magma‐poor rifted continental margin of Galicia has an extremely complex structure. Its formation involved several rifting episodes that occurred ultimately during the early Cretaceous near a ridge triple junction, which produced a change in the orientation of the main structures in its transition to the north Iberia margin. In addition, there is a superimposed partial tectonic inversion along its northwest and northern border which developed from the Late Cretaceous to at least Oligocene times. The present study integrates a large volume of new geophysical information (mainly marine gravity data and 2D seismic reflection profiles) to provide insights on the formation of this rift system and on the development of its later inversion. The combined...
Tipo: Text
Palavras-chave: Rifted margin; Hyperextension; Tectonic inversion; Crustal domains; Structural domains; Gravity.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00438/54975/56420.pdf

Reply to Comment by A. Argnani on "Geometry of the Deep Calabrian Subduction from Wide‐Angle Seismic Data and 3‐D Gravity Modeling"
Provedor de dados: 5
Autores: Dellong, David; Klingelhoefer, Frauke; Dannowski, Anke; Kopp, Heidrun; Murphy, Shane; Graindorge, David; Margheriti, Lucia; Moretti, Milena; Barreca, Giovanni; Scarfì, Luciano; Polonia, Alina; Gutscher, Marc-andre.
Andrea Argnani in his comment on Dellong et al., 2020 (Geometry of the deep Calabrian subduction (Central Mediterranean Sea) from wide‐angle seismic data and 3D gravity modeling), proposes an alternate interpretation of the wide‐angle seismic velocity models presented by Dellong et al., 2018 and Dellong et al., 2020 and proposes a correction of the literature citations in these paper. In this reply, we discuss in detail all points raised by Andrea Argnani.
Tipo: Text
Palavras-chave: Wide-angle seismic; Ionian basin; Gravity.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00640/75196/75326.pdf

Geometry of the deep Calabrian subduction (Central Mediterranean Sea) from wide‐angle seismic data and 3‐D gravity modeling
Provedor de dados: 5
Autores: Dellong, David; Klingelhoefer, Frauke; Dannowski, Anke; Kopp, Heidrun; Murphy, Shane; Graindorge, David; Margheriti, Lucia; Moretti, Milena; Barreca, Giovanni; Scarfì, Luciano; Polonia, Alina; Gutscher, Marc-andre.
The Calabrian subduction zone is one of the narrowest arcs on Earth and a key area to understand the geodynamic evolution of the Mediterranean and other marginal seas. Here in the Ionian Sea, the African plate subducts beneath Eurasia. Imaging the boundary between the downgoing slab and the upper plate along the Calabrian subduction zone is important for assessing the potential of the subduction zone to generate mega‐thrust earthquakes and was the main objective of this study. Here we present and analyze the results from a 380 km long, wide‐angle seismic profile spanning the complete subduction zone, from the deep Ionian Basin and the accretionary wedge to NE Sicily, with additional constraints offered by 3‐D Gravity modeling and the analysis of earthquake...
Tipo: Text
Palavras-chave: Ionian Basin; Wide-angle seismic; Gravity; Crustal structure; Seismicity; Tomography.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00592/70442/68544.pdf

Geodynamics of the South China Sea
Provedor de dados: 5
Autores: Sibuet, Jean-claude; Yeh, Yi-ching; Lee, Chao-shing.
The beginning of seafloor spreading in the South China Sea (SCS) is now established from IODP drilling Leg 349 at 33 Ma. Chron 12 (32 Ma) is the oldest chron identified in the SCS. The nature of the crust of the northeastern part of the SCS located north of chron C12, where chrons 15 to 17 were previously identified, is not oceanic but thinned continental crust intruded by volcanic elongated features emplaced 17-22 Ma ago. Based on magnetic anomalies identifications, the end of the SCS spreading could be either 15.5, 20.5 Ma (Briais et al., 1993; Barckhausen et al., 2014) or something else. However, as post-spreading magmatic activity (~ 13-3.5 Ma) largely masks the spreading fabric in particular near the axis of the east sub-basin, published locations of...
Tipo: Text
Palavras-chave: South China Sea; Gravity; Magnetics; Structural and tectonic analyses; Kinematics.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00316/42686/42059.pdf

Market Access Asymmetry in Food Trade among Quad Countries
Provedor de dados: 31
Autores: Olper,   Alessandro; Raimondi,   Valentina.
This paper uses a gravity-like structure derived from a monopolistic competition model to measure market access among Canada, USA, Japan and EU – Quad countries – over the 1996-2001 period. We explore the overall asymmetry and 18 food industrial-level asymmetries of bilateral trade openness. Using actual bilateral estimates of tariffs and nontariff barriers, we investigate their role in explaining the trade reduction effect of national borders. A representative estimate of market access shows that higher asymmetries exist in USA, Canada and EU trade with Japan. Quite surprisingly, the last country is always more open than the reverse. Finally, we found that tariffs and NTBs explain a significant part of the border effects and that the NTB role is often...
Tipo: Conference Paper or Presentation
Palavras-chave: Market access; Food trade; Asymmetry; Gravity; QUAD countries; International Relations/Trade; F13; F14; Q17.
Ano: 2005
URL: http://purl.umn.edu/24596

Explaining National Border Effects in the Quad Food Trade
Provedor de dados: 31
Autores: Olper,   Alessandro; Raimondi,   Valentina.
Starting from a theoretically consistent gravity model, this paper first provides estimates of bilateral 'border effects' in food trade among Quad countries (Canada, USA, Japan and EU) at the ISIC 4-digit level. Then, it investigates the underlying reasons of border effect, assessing the role played by policy barriers (tariffs and non-tariff barriers) with respect to barriers unrelated to trade policy, such as information related costs and cultural proximity. In contrast with several previous findings, we show that policy barriers are part of the story in explaining the strong trade reduction effect induced by national borders, and this is especially true when we control for the endogeneity of trade policy to imports, as suggested by political economy...
Tipo: Conference Paper or Presentation
Palavras-chave: Border effect; Food trade; Market access; Gravity; QUAD countries; International Relations/Trade; F13; F14; Q17.
Ano: 2006
URL: http://purl.umn.edu/25467

China's Growth, World Food Prices, and Developing Countries Exports
Provedor de dados: 31
Autores: Villoria,   Nelson.
This paper explores the impacts of China's growth in the international markets of agricultural products. These impacts are important because they are related to two different ongoing discussions about the role of China in the world economy. One of these discussions have to do with China as a source of price inflation while the other has to do with China as an engine of growth for developing countries, in this case, through increased export opportunities. Our results suggest that China has been a source of aggregated mild price inflation in the largest developed economies that occupy the first ranks as food importers. This is probably related to a more intense pressure on world food supplies. When we look at the counterfactual exports of selected exporters,...
Tipo: Conference Paper or Presentation
Palavras-chave: Gravity; China; Food prices; International Development; International Relations/Trade.
Ano: 2009
URL: http://purl.umn.edu/49398

Preferences Erosion and Trade Costs in the Sugar Market: The Impact of the Everything but Arms Initiative and the Reform of the EU Policy
Provedor de dados: 31
Autores: Conforti,   Piero; Rapsomanikis,   George.
The changes recently introduced in the EU Common Market Organization for sugar will interact with preferential imports from developing countries and least developed countries that enjoy preferential treatment for exports to the EU, as well as by trade and adjustment costs. This paper focuses on the impact of the EU Commission’s sugar policy reform and the Everything But Arms initiative on the African, Caribbean and Pacific countries and the Least Developed Countries. Simulations are run with an empirical model structure comprising a partial equilibrium model for the world sugar market and a gravity model to replicate least developed countries bilateral trade with Europe. Particularly, the gravity approach is employed to model the abolition of import...
Tipo: Conference Paper or Presentation
Palavras-chave: EBA; Sugar; Gravity; Trade; C53; International Relations/Trade; Q18; C23.
Ano: 2006
URL: http://purl.umn.edu/25641

PATTERNS AND DETERMINANTS OF INTERNATIONAL TRADE COSTS IN THE FOOD INDUSTRY
Provedor de dados: 31
Autores: Olper,   Alessandro; Raimondi,   Valentina.
Replaced with revised version of paper 07/16/07.
Tipo: Conference Paper or Presentation
Palavras-chave: Trade costs; Gravity; Processed Foods; Geography; Infrastructure; Trade Policy; Inequality; Agribusiness; International Relations/Trade; F1; F13; F14.
Ano: 2007
URL: http://purl.umn.edu/9799

Production aspects of broiler breeders submitted to different drinker types
Provedor de dados: 89
Autores: Colvero,LP; Carrijo,AS; Garófallo,RG; Bernardi,R; Steffen,RPB; Stefanello,C.
The objective of this study was of evaluate the influence of different drinker types on the egg production, water intake, mortality, poultry litter relative humidity, egg weight, eggshell percentage, and egg specific gravity of broiler breeders. The experiment was carried out in a commercial farm with 37- to 44-wk-old broiler breeders. A randomized block experimental design, consisting of two treatments (bell or nipple drinkers) with four replicates of 4.000 females each, was applied. Data were submitted to analysis of variance, and means were compared by the test of Student-Newman-Keuls at 5% significance level. Birds submitted to nipple drinkers presented lower water intake (p&lt;0.05). There was no influence (p&amp;gt;0.05) of drinker type on egg...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Intake; Gravity; Nipple drinkers; Bell drinker; Egg production.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2014000100009