The little-known small volcanoes of Mars

Huge volcanoes with diameters of >>100 km are well known from \nMars. However, the planet‘s two largest volcanic provinces, Tharsis \nand Elysium, are also strewn with hundreds of small shield volcanoes, \nwith diameters of several kilometers to tens of kilometers and heights \nof only a few hundred meters. These low shields are hard to detect \nin low-resolution images, and they only became accessible for analysis \nafter the acquisition of high-resolution images and topographic data \nin the last few years. They are characterized by radial patterns of lava \nflows and extremely shallow flank slopes of typically <0.5°, indicating \nlow-viscosity lavas. Many other volcanic features are associated \nwith the low shields, such as craters, fissure vents, cinder and spatter \ncones, lava flows, which are commonly associated with lava channels \nand tubes, lava inflation features, and volcanic rift zones, all of which \nhave terrestrial analogs in basaltic volcanic provinces. The distribution \nof low shields does not show any obvious association with large-scale \ntectonic features. The low shields might represent a recent type of volcanism, \nwhich is not related to mantle plumes, but to a zone of partial \nmelting in an anomalously warm mantle underneath a thickened crust. \n \n \n