Summary The research aimed to determine the influence of the flipped classroom as a tool for the achievement of autonomous learning in university students. The type of study that was used was applied and the experimental design of a quasi-experimental sub type. The sample consisted of 73 students distributed in 2 groups of which one was the control group (37) and the other the experimental group (36), students of both sexes, for which an intentional Non-Probabilistic sampling was used. In relation to the technique, this was the survey as instruments the questionnaire that was applied virtually which went through two phases before being applied to the study sample (validity and reliability), in relation to the reliability a value was obtained of 0.864 according to KR20. The pre-test results in relation to autonomous learning 38.9% and 43.2% of the students in the control group (CG) and experimental group (EG) maintain a low level, likewise, 58.3% and 43, 2% present a medium level, for their part, 2.8% of the control group and 13.6% of the experimental group were at the high level. It was concluded that the flipped classroom allows the student to learn autonomously, incorporating TIC as an innovative element in the transformation of the acquisition of new learning in a responsible manner.

Resumen La investigación tuvo como objetivo determinar la influencia del aula invertida como herramienta para el logro de aprendizaje autónomo en estudiantes universitarios. El tipo de estudio fue aplicada y el diseño experimental de sub tipo cuasi experimental. La muestra estuvo conformada por 73 estudiantes distribuidos en 2 grupos de los cuales uno fue el grupo control (37) y el otro el grupo experimental (36), estudiantes de ambos sexos, para lo cual se utilizó un muestreo No Probabilístico de tipo intencional. Con relación a la técnica, ésta fue la encuesta como instrumentos el cuestionario que fue aplicado de manera virtual el cual pasó por dos fases antes de ser aplicado a la muestra de estudio (validez y confiabilidad), con relación a la confiabilidad se obtuvo un valor de 0,864 según KR20. Los resultados del pretest en relación con el aprendizaje autónomo un 37,6% y 41,2% de los estudiantes del grupo control (GC) y grupo experimental (GE) mantienen un nivel bajo, asimismo, un 57,1% y 41,5% presentan un nivel medio, por su parte, el 5,3% del grupo control y el 17,3% del grupo experimental se situó en el nivel alto. Se llegó a la conclusión que el aula invertida, permite al estudiante aprender de manera autónoma incorporando las TIC como elemento innovador en la trasformación de la adquisición de los nuevos aprendizajes de manera responsable.

RESUMO: A margem continental uruguaia é resultado da fragmentação do supercontinente Gondwana e posterior abertura do Oceano Atlântico, iniciados no Jurássico. Três bacias sedimentares estão presentes na margem continental do Uruguai: a Bacia de Punta del Este, a porção mais austral da Bacia de Pelotas e a Bacia Oriental del Plata. As bacias da margem continental do Uruguai compartilham os clássicos estágios tectono-sedimentares evolutivos das demais bacias marginais atlânticas, incluindo as fases pré-rifte (Paleozoico), rifte (Jurássico-Cretáceo Inferior), transição (Barremiano-Aptiano) e pós-rifte (Aptiano-Presente). Quatro sistemas petrolíferos especulativos foram definidos para a Bacia Punta del Este, baseados na análise de seções sísmicas e dados de poços e no estabelecimento de analogias com as bacias marginais atlânticas productoras de hidrocarbonetos: 1) sistema petrolífero marinho da fase pré-rifte: Devoniano/Permiano-Devoniano/Permiano(?), 2) sistema petrolífero lacustre da fase rifte: Neocomiano/Neocomiano(?), 3) sistema petrolífero marinho da fase pós-rifte cretácea: Aptiano-Cretáceo Superior(?), 4) sistema petrolífero marinho da fase pós-rifte cenozoica: Paleoceno-Paleogeno/Neogeno(?).

ABSTRACT: The Uruguayan continental margin was generated as the result of the breakup of Gondwana and, later, the opening of the South Atlantic Ocean, which began in the Jurassic. Three major areas of Meso-Cenozoic sedimentation are located in the Uruguayan offshore: the Punta del Este Basin, the southernmost sector of the Pelotas Basin and the Oriental del Plata Basin. These basins share the classical stages of tectono-sedimentary evolution of the other Atlantic basins, including the prerift (Paleozoic), rift (Jurassic-Early Cretaceous), transition (Barremian-Aptian) and postrift (Aptian-present) phases. Based on the analysis of basin evolution through seismic sections and well data as well as on the establishment of analogies with productive Atlantic basins, four speculative petroleum systems are proposed for the Punta del Este Basin: 1) Marine petroleum system of the prerift stage: Devonian/Permian-Devonian/Permian(?), 2) Lacustrine petroleum system of the synrift stage: Neocomian-Neocomian(?), 3) Marine petroleum system of the Cretaceous postrift: Aptian-Late Cretaceous(?), 4) Marine petroleum system of the Cenozoic postrift: Paleocene-Paleogene/Neogene(?).

The Santa Lucia Basin is located in southern Uruguay, and covers about 8.000 km2. It has an elongated shape with an east-northeast trend (Fig. 1). The basin was classified as a failed rift formed during the Gondwanaland breakup (Sprechmann et al., 1981). The Santa Rosa structural high, which is located in the central region of the basin, divides it in two sub-basins. This high is parallel to the basin borders. The Cretaceous volcanic and sedimentary filling is 2400 m thick; whereas, the Cenozoic sediments are only a few tens of meters thick (de Santa Ana et al., 1994). This paper deals with the description and genetic interpretation of the carbonate deposits present in the Santa Lucia basin. These deposits were considered as part of the Upper Cretaceous Mercedes Formation (Bossi et al., 1975). The coarse-grained sandstones and conglomerates, with trough and planar cross-bedding that composed this unit were interpreted as being deposited in a low sinuosity fluvial system. The unit is underlain by the Cretaceous Migues Formation and overlain by Oligocene Fray Bentos Formation (Fig. 2). The carbonate deposits were formerly correlated to the “Calizas del Queguay” deposits that crop out in western Uruguay. Different authors (Lambert, 1940; Jones, 1956; Goso, 1965; Goso & Bossi, 1966; Gómez et al., 1981; Preciozzi et al., 1985; Bossi & Navarro, 1991; de Santa Ana et al., 1994) assigned to these deposits lacustrine origin. The present investigation involves the construction of detailed sedimentological profiles, facies and petrographic analysis. Based on the lateral and vertical relationships between the siliciclastic and carbonate facies and on the microscopic characteristics, this study considers the carbonate deposits, almost entirely, as non-pedogenic groundwater calcretes. The main evidences of calcretization are: replacement and/or transformation of the siliciclastic material by calcite (Fig. 7), infilling of the intergranular spaces by calcite (Fig. 9), reprecipitation of silica (Fig. 8), gradual increase of the calcite content and the preservation of the primary sedimentary bodies (Fig. 6). The detailed stratigraphic analysis shows that, even though, the Santa Lucia calcretes are generally micritic, they are sandy and sometimes gravelly calcretes. The relationship with the siliciclastic facies is gradational, although sometimes abrupt changes occur. It is characterized by an increase in the carbonate cement which finally completely replaces the primary lithofacies. The calcretes form isolated tabular bodies with a maximum thickness of 5 meters. These bodies are usually aligned with the Santa Rosa high, and in the southern border of the basin they are overlaying the basement (Fig. 1). Under arid and warm climatic conditions, calcretization is controlled by the texture of the sedimentary rocks, the structural elements of the basin including its boundaries, and by the surface drainage flow patterns. In Santa Lucia basin the latter is controlled by a regional relict slope, showing a southward-southeastward flow and similar to that one of the Cretaceous fluvial systems. The subsurface waters that flowed through the Mercedes sandstones may have been enriched in carbonates supplied by Cretaceous basalts and part of the Precambrian carbonate platforms that were exposed in the central-eastern region of Uruguay during the calcrete formation (Fig. 10) The calcretization process occurred after the deposition of the Upper Cretaceous Mercedes Formation and before the accumulation of the fine sediments that constitute the Oligocene-Early Miocene? Fray Bentos Formation (Fig. 2). In fact, in the study area the carbonate rocks containing the fossils that were described by Frenguelli (1930) are directly overlaying the non-pedogenic calcretes. This rocks are interpreted as paleosoils, on the basis of geometric, petrographic and paleontologic evidences. The fossil record from the paleosoils suggest a Paleogene age.

Los depósitos carbonáticos existentes en la Cuenca de Santa Lucía, sur del Uruguay, han sido considerados pertenecientes a la Formación Mercedes (Cretácico Superior) e interpretados como depósitos de origen lacustre. Estos depósitos se correlacionan con las calizas silíceas y arenosas que se desarrollan en el litoral-oeste del Uruguay, pudiendo ser genéricamente denominados como “Calizas del Queguay”. Observaciones detalladas de campo y microscópicas permiten descartar el origen lacustre de las calizas de la Cuenca de Santa Lucía y postular que las mismas constituyen un evento post-depositacional. Las calizas son interpretadas como calcretas de aguas subterráneas, asociándose localmente un nivel de calcretas pedogénicas. Las principales evidencias del proceso de calcretización son: el reemplazo y/o la transformación de elementos clásticos silíceos pre-existentes por carbonato, el relleno de los espacios intergranulares por carbonato, la presencia de figuras de corrosión y disolución en los componentes cuarzosos, la reprecipitación de sílice, la gradación de los términos silicoclásticos hasta calcáreos por aumento creciente de carbonato y la preservación de geometrías relictuales del depósito original. El origen pedogénico del nivel calcáreo se apoya también en la existencia de una característica asociación fosilífera. La distribución espacial de las calcretas sugiere la actuación del Alto de Santa Rosa en el control de los principales frentes de carbonatación. El proceso de calcretización afectó, particularmente, a las sedimentitas clásticas de la Formación Mercedes. Esta unidad se comportaba como un acuífero por el que circulaban aguas ricas en carbonatos. Dos posibles fuentes de aporte carbonático son consideradas: las secuencias plataformales carbonáticas precámbricas y los basaltos cretácicos. El clima debió ser árido y cálido. La edad del proceso, si bien no es posible definirla con precisión, está acotada entre el Cretácico Superior y el Oligoceno, considerándose Paleógena la edad más probable teniendo en cuenta el contenido fosilífero de las calcretas pedogénicas.