La evolución tectonosedimentaria de las Baleares: Análisis crítico

El análisis crítico de la bibliografía existente sobre la Geología de las Baleares, a la luz de nuestros datos recientes, fundamentalmente sedimentológicos, del Terciario y del Mesozoico de Mallorca, permite modificar el modelo hasta ahora establecido para explicar la evolución tectonosedimentaria de las Baleares. La hipótesis que se plantea modifica las "series de escamas" cabalgantes postburdigalienses y replantea antiguas ideas estructurales -compartimentación por fracturas verticales- combinadas con corrimientos gravitacionales curante el Mesozoico, el Paleógeno y el Neógeno. Esta hipótesis concuerda con la establecida a partir de las investigaciones de Geología marina para explicar las cuencas del Mediterráneo occidental

Características de las secuencias deposicionales de alta frecuencia en el sistema arrecifal del Mioceno superior de Mallorca

Application of sequence stratigraphy concepts in well-exposed prograding carbonate complexes, such as the example of Mallorca, shows marked peculiarities differing from the commonly used as standard model of the Exxon group. These peculiarities are seen in high-frequency sequences bounded by well-definederosion surfaces. The standard model is incomplete in the sense that it shows no sedimentary record of the fall of the sea-level cycle, except for erosion or karstification. In contrast, the Mallorcan example shows more complete and continuous sedimentary record during the entire sea-level cycle: an offlapping package, commonly ignored or misinterpreted, is deposited during the internal of sea-level fall, and considered as a new systems tract. As a result, the most obvious and marked erosion surface separating these high-frequency packages is the sequence boundary. Furthermore, in the standard model the downlap surface is correlative with the maximum flooding surface and a condensed section. In contrast, the Mallorcan model shows that a condensed section and downlap surface are produced during the offlapping systems tract, whereas the maximum flooding surface are indistinct. There are two surfaces easily recognized in the Mallorcan example: an erosion surface and a downlap surface. On this basis there are two major systems packages or tracts: a lower package with aggradation in all the systems formed during sea-level rise and high-stillstand and an upper package with offlapping progradation formed during sea-level fall and low-stillstand. Al1 the above peculiarities of the Mallorcan prograding reef complex show the need for careful application of the dynamic concepts of sequence stratigraphy, rather than the strict reference to the standard scheme. The relationships between carbonate production and each segment of the sea-level cycle explain these departures from the standard 3rd-order sequencemodel developed from siliciclastic deposits on passive margins

Características de las secuencias deposicionales de alta frecuencia en el sistema arrecifal del Mioceno superior de Mallorca

Application of sequence stratigraphy concepts in well-exposed prograding carbonate complexes, such as the example of Mallorca, shows marked peculiarities differing from the commonly used as standard model of the Exxon group. These peculiarities are seen in high-frequency sequences bounded by well-definederosion surfaces. The standard model is incomplete in the sense that it shows no sedimentary record of the fall of the sea-level cycle, except for erosion or karstification. In contrast, the Mallorcan example shows more complete and continuous sedimentary record during the entire sea-level cycle: an offlapping package, commonly ignored or misinterpreted, is deposited during the internal of sea-level fall, and considered as a new systems tract. As a result, the most obvious and marked erosion surface separating these high-frequency packages is the sequence boundary. Furthermore, in the standard model the downlap surface is correlative with the maximum flooding surface and a condensed section. In contrast, the Mallorcan model shows that a condensed section and downlap surface are produced during the offlapping systems tract, whereas the maximum flooding surface are indistinct. There are two surfaces easily recognized in the Mallorcan example: an erosion surface and a downlap surface. On this basis there are two major systems packages or tracts: a lower package with aggradation in all the systems formed during sea-level rise and high-stillstand and an upper package with offlapping progradation formed during sea-level fall and low-stillstand. Al1 the above peculiarities of the Mallorcan prograding reef complex show the need for careful application of the dynamic concepts of sequence stratigraphy, rather than the strict reference to the standard scheme. The relationships between carbonate production and each segment of the sea-level cycle explain these departures from the standard 3rd-order sequencemodel developed from siliciclastic deposits on passive margins

El Mioceno de la Sierra Norte de Mallorca (Sector centro-occidental)

Se estudian los depósitos burdigaliense-langhiense del sector centro-occidental de la Sierra Norte de Mallorca. Se reconocen en elios dos secuencias deposicionales de carácter transgresivo. En la primera se despositan, sobre un basamento mesozoico alterado, sedimentos litorales y de plataforma. En la segunda y como consecuencia de un brusco aumento de la inestabilidad tectónica, se depositan secuencias turbidíticas que llegan a organizarse como abanicos submarinos de pequeñas dimensiones

El Mioceno de la Sierra Norte de Mallorca (Sector centro-occidental)

Se estudian los depósitos burdigaliense-langhiense del sector centro-occidental de la Sierra Norte de Mallorca. Se reconocen en elios dos secuencias deposicionales de carácter transgresivo. En la primera se despositan, sobre un basamento mesozoico alterado, sedimentos litorales y de plataforma. En la segunda y como consecuencia de un brusco aumento de la inestabilidad tectónica, se depositan secuencias turbidíticas que llegan a organizarse como abanicos submarinos de pequeñas dimensiones

Presencia de Caliche Fósil en el Buntsandstein del vall del Congost (Provincia de Barcelona)

The prosence of fossil caliche of Lower Triassic age is pointed out and it is interpretad as eariy mature caliche resulting from shart subaerial exposures in semiarid conditions. Two lcinds of cnvironments are deduced in accordance to those two models of lithdogicd scequences where the caliche is founded: dista1 piedmont alluvial plains and "playas", and levees and ponds in a meandering plain

Procesos telodiagenéticos en rocas carbonatadas del litoral catalán y baleares: su relación con microorganismos

Esta tesis estudia la relación existentre entre los proceosos de alteración de las rocas carbonatadas y los microorganismos, a los distintos niveles existentes entre la superficie de la roca y la superficie piezométrica: superficial, fisural, edáfico, de cavidades cársticas vadosas y al nivel freático

Presencia de Caliche Fósil en el Buntsandstein del valle del Congost (Provincia de Barcelona)

Se señala la presencia de caliche fósil en el Triásico inferior y el cual es interpretado como caliche inicialmente maduro producido en cortas exposiciones subáreas en condiciones semiáridas. Se deducen das tipos de ambientes de acuerdo con los dos modelos $e secuencias litolgicas en las que se encuentra el caliche: partes distale de glacis de acumulación y 'playas', y diques y charcas en una llanura aluvial meandriforme