Tectonic control in the boundaries of the genetic units: an example in the Dogger of the External Zones of the Betic Cordillera (province of Murcia and Almeria, Spain)
1995; Elsevier BV; Volume: 95; Issue: 1-2 Linguagem: Inglês
10.1016/0037-0738(94)00097-e
ISSN1879-0968
Autores Tópico(s)Paleontology and Stratigraphy of Fossils
ResumoAbstract I have studied the evolution of a genetic unit of the Dogger to the north of Velez-Rubio (External Zones of the Betic Cordilleras, southeast Spain). This unit, at its lower and upper boundaries, is limited by sedimentary breaks of the uppermost Toarcian and intra-upper Bathonian, respectively. Starting from the analysis and distribution of facies (rich in ostracods, oncolites, oolites, crinoids, peloids, pelagic pelecypods or deposited particles) on diverse drawn columns, the lateral and vertical evolution in this section of the basin for this period of time can be deduced. This permits the differentiation between systems tracts (lowstand systems tract, LST; transgressive systems tract, TST; and highstand systems tract, HST) with a slightly homogeneous distribution, which can be related to an uneven morphology of the substratum. Different factors that controlled the evolution of the basin during this period of time have been analysed; from this we can deduce that the role of tectonics could be dominant as contrasted with that of eustasy. An anomalous evolution toward the top of the highstand systems tract is indicated. In this unusually thick succession some evidence of retrogradation can be deduced. This could not be explained eustatically but it could certainly be explained tectonically.
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