Syrtis Major Planum: Diferenzas entre revisións

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==Xeografía e xeoloxía==
Syrtis Major está centrada sobre as coordenadas 9,2° N 67,1° E<ref name="nomenclatura Syrtis"/>, estendese por unha area dun diámetro aproximado de 1.200 km<ref name="nomenclatura Syrtis"/> na parte máis oriental de [[Terra Sabaea]] e lindando con [[Isidis Planitia]] e [[Terra Thyrrena]],<ref name="fronteiras Mola">{{cita web | url= http://planetarynames.wr.usgs.gov/images/mola_regional_boundaries.pdf | título=Appoximate Boundaries for Mars Regional Feature Names | dataacceso=12-03-2012}}</ref> o cuadrante MC-13 de Marte leva o seu nome.<ref name="cuadrantes Mola">{{cita web | url= http://planetarynames.wr.usgs.gov/Page/mars1to5mMOLA | título= Planetary Names: Mars 1:5 million-scale MOLA Images | dataacceso=12-03-2012}}</ref> Polo oeste e pegada a [[Arabia Terra]] comeza a elevarse moi suavemente ata caer case en picado cando chega ó borde de [[Isidis Planitia]]. A chaira inclúe un avultamento que case acada os 6 km de altitude. A meirande parte de Syrtys Major ten unha inclinación menor dun grao, unha inclinación incluso moito menor cá dos volcáns de escudo de [[Tharsis (Marte)|Tharsis]]. Practicamente no centro da rexión pódese atopa-la depresión alongada que contén as caldeiras de [[Nili Patera]] e [[Meroe Patera]], as cales acadan os 2 km de profundidade. Os chas destas paterae non son elevados se os comparamos cos terreos que rodean a Syrtis Major. O chan de Nili Patera está menos craterizado, e polo tanto é o máis novo dos dous. Nili Patera é de especial interese para os científicos, xa que a diferencia da meirande parte de Marte, neste patera atopouse [[dacita]], a parte de [[basalto]].<ref name="THEMIS">{{cita web
Syrtis Major está centrada sobre as coordenadas 9,2° N 67,1° E <ref name="nomenclatura Syrtis"/>, extends some {{convert|1,500|km|mi|abbr=on}} north from the planet's equator, and spans {{convert|1,000|km|mi|abbr=on}} from west to east. It is in the [[Syrtis Major quadrangle]]. It encompasses a large slope from its western edge at [[Aeria]]{{Disambiguation needed|date=June 2011}} dropping {{convert|4|km|mi|abbr=on}} to its eastern edge at [[Isidis Planitia]]. It includes a high-altitude bulge that rises {{convert|6|km|mi|abbr=on}} at 310° W. Most of Syrtis Major has slopes of less than 1°, a much lower inclination than the slopes of the [[Tharsis]] shield volcanoes. It has a 350x150 km north-south elongated central depression containing the [[caldera]]s [[Nili Patera]] and [[Meroe Patera]], which are about 2&nbsp;km deep. The floors of the calderas are not elevated relative to the terrain surrounding Syrtis Major. The floor of Nili Patera is the less cratered, and therefore the younger, of the two. While most of the rock is basaltic, [[dacite]] has also been detected in Nili Patera.<ref name="THEMIS">{{cite web
| titletítulo = [[2001 Mars Odyssey|Mars Odyssey Mission]] [[Thermal Emission Imaging System|THEMIS]] web site
| datedata = 23 October -10-2006
| url = http://themis.asu.edu/features/nilipatera
| accessdatedataacceso = 200712-0903-082012
}}</ref> Satellite gravity field measurements show a positive gravity anomaly centered on the caldera complex, suggesting the presence of a 600x300 km north-south elongated extinct [[magma chamber]] below, containing dense minerals (probably mainly [[pyroxene]], with [[olivine]] also possible) that precipitated out of [[magma]] before eruptions.<ref>{{cite journal
| last = Kiefer