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The Lower Paleogene Chicontepec Foreland Basin at the southern region of the Tertiary Tampico-Misantla Basin at East-Central Mexico, resulting from the loading pressure of the uplifted and thrust-folded front of the Sierra Madre Oriental, on the passive, unfolded and thermally in subsidence Cretaceous basement, during the northeastward tectonic stresses from the Laramide Orogeny, against the Tuxpan Island eastern. The foreland basin consists stratigraphically of complex low density turbidite systems, being their detached and non-channelized outer-fan lobe facies the most conspicuous, composite by disperse and discontinue sandy lenses with tight and highly cemented calcareous lithofacies, micro-fractured and with micro-vugs by dissolution. The hydrocarbons flowed vertically from the underlay Cretaceous and Upper Jurassic rocks through the NW-SE dextral transpressive strike-slip fault planes and fractures, then spread laterally toward the micro-fractured sandy lenses and within the unconformable erosive surfaces, bounding the depositional systems (systems tracts), at different levels of the Chicontepec stratigraphic column, in a hybrid petroleum system with low permeability unconventional reservoirs.

A track-bearing locality in one of the shores of the Ñumí River, near the City of Tlaxiaco, northwestern Oaxaca, southern Mexico, preserves the footprints of sauropod and theropod dinosaurs; it is located within the stratigraphic sequence of the Zorrillo-Taberna Indiferenciadas Formation, of Middle Jurassic (Bajocian) age. A well-preserved manus-pes set of ankylosaurian affinity (Tetrapodosaurus) is preserved on a rock block from this formation. These tracks are preserved as convex hyporeliefs. The pes impression is tetradactyl, with ventrally curved toe tips, suggesting that these were deeply impressed in the sediment. Manus impression is pentadactyl, with short and blunt digits. A curved structure preserved together with these footprints is herein interpreted to be a tail drag. The stratigraphic unit from whence this block came was identified and two additional ankylosaurian tracks, were found preserved in situ as natural sandstone casts. An isolated handprint, has the same features that fit the ankylosaurian hand morphology; however, some features such as a medio-lateral concavity are indicative of the presence of a well-developed palmar pad, and could suggest the functional mechanics of the ankylosaurian manus. The Zorrillo-Taberna Indiferenciadas Formation is a coal-bearing formation; after the global record, ankylosaur footprints are concentrated in coal-bearing and floodplain facies, thus suggesting, that at least the North American Ankylosauria were adapted to similar paleoecological conditions from Middle Jurassic to Early Cretaceous times. It represents the second report of ankylosaurian tracks from Mexico and the southernmost record of the ichnogenus Tetrapodosaurus in North America. In this way, it suggests a geographic continuum in the record of the Ankylosauria to southern North America during Middle Jurassic times. With their Middle Jurassic age, these footprints represent the oldest ankylosaurian ichnofossils known to date.

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251 ResumenPara prevenir eventuales inundaciones de gran extensión producidas por precipitaciones pluviales intensas que saturen el drenaje actual en la Ciudad de México y municipios conurbados del Estado de México, se propone una nueva salida artificial de agua de la Cuenca de México por su extremo sureste. Ello, mediante un canal y un túnel excavados en la secuencia lacustre, en rocas volcánicas de la Faja Volcánica Mexicana y en la secuencia clástica de la Cuenca del Balsas. Se propone que la obra se realice siguiendo la vía de ferrocarril abandonada (zona federal), desde la localidad de Xico en el Estado de México hasta el Río Cuautla, al norte de Cuautla, Morelos.Palabras clave: Cuenca de México, inundación, drenaje. Abstract In order to avoid possible floods of great extension produced by intense pluvial precipitations that overflow the current drainage in Mexico City and suburban municipalities of the State of Mexico, a new artificial water exit in the Mexico basin at its southeastern end is proposed. This would consist in a channel and a tunnel excavated in the lacustrine sequence, in volcanic rocks of the Trans-Mexican