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Imágen SPOT del Volcán de Colima en donde se observa la red de drenajes que concentran los escurrimentos pluviales hacia la zona metropolitana de Colima-Villa de Álvarez, Estado de Colima, México (Fuente imagen ERMEX-SPOT IMAGE S.A.); véase el artículo relacionado de Pérez-González et al. en este número.

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Thin section under petrographic microscope of fossil remains of the rebbachisaurid sauropod Katepensaurus goicoecheai of Bajo Barreal Formation (Upper Cretaceous, Argentina). Part of a permineralized vascular canal is observed, including a first layer of hematite, a second layer of silica as chalcedony and quartz, and a third layer in the center that fills completely the canal with zeolites (crossed nicols). See Casal et al. (2017) in this issue.

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Labial view of Neochoerus occidentalis from late Blancan of Tecolotlán basin, Jalisco, Mexico. The masseteric ridge ends in p4, the entire simphysis and the complete incisor ends in the second prism of the first molar in the lingual side; The genus Neochoerus is among the first neotropical migrants in the central region of Mexico; see article by Carranza-Castañeda in this issue. Photo by: J. Jesús Silva Corona.

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In northern Sierra Plomosa, south of Placer de Guadalupe –a classical locality of paleozoic exposures 100 km northeast of Chihuahua City– a siliciclastic Lower to Middle Jurassic marine-marginal succession, rest unconformable on carboniferous limestones of the Pastor Formation. The siliciclastic unit, considered previously as Early Permian in age was recently dated as Early to Middle Jurassic according to U-Pb (zr) ages from ignimbrite and rhyolitic flows that occur concordant in the succession. Photo by: José Rafael Barboza Gudiño, 2012.

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Rincón de Parangueo, located in the Santiago Valley, in the State of Guanajuato is a maar that has dried due to the large groundwater ex­traction required for irrigating crops in the region. The active deformation of the maar’s bottom (which includes both uplift and subsidence) has created a series of structures on its surface. Photo: Jaime J. Carrera-Hernández.

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Chevron folds in quartz schists of the Neoproterzoic Difunta Correa Metasedimentary Sequence, Sierra de Pie de Palo, Argentina. Photo by : Agustín Kriscautzky (geology student, Universidad Nacional de Córdoba, Argentina).

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View to the NW of Sierra de la Giganta, from the road to Agua Verde, Baja California Sur. The sierra is made up of rocks of the early to late Miocene Comondú Group, mainly massive andesitic breccias, conglomerate and sandstone, with subordinate volumes of domes, lava flows and dikes. Photo: Teresa Orozco.