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Daniel Jimenez de Cisneros
Next September the village of Crevillente will be organised a summer course inside the offer of the Miguel Hernández University summer course entitled “Jimenez de Cisneros, pioneer in the geological and paleontological investigation in the Southern Alicante”.
Presentation
This year marks the centenary of Daniel Jiménez de Cisneros, Professor of Natural History, publication in the “Iberia” journal, of the first geological and paleontological synthesis of the Crevillente Sierra.
Daniel Jiménez de Cisneros made what could be the first and oldest photographs of the Crevillente Sierra, an exceptional graphic testimony that allows us to see what the landscape of this mountain was like 100 years ago. We also owe him not only the identification of the main paleontological sites of the mountains, but also the approach of the first geological itineraries on it, published in the “Iberia” journal in 1919.
This course makes this figure known to us and brings us closer to the geology and paleontology of our environment by the help of great specialists.
Ana Satorres course coordinador.
More information about the Crevillente course here.
One of the events of this course will be a field trip to the Crevillente Sierra to see the some of the historical sites mentioned in the 100-year-old paper of Jimenez de Cisneros conducted by Jose Enrique Tent- Manclus.
All the news about the event will be comment in this blog.
The Agost Basin (Betic Cordillera, Alicante province, Spain): a pull-apart basin involving salt tectonics
A new work to illustrate a strike-slip basin in the Betics. Here the link to the publisher.
The Agost Basin is characterized by a Miocene-Quaternary shallow marine and continental infilling controlled by the evolution of several curvilinear faults involving salt tectonics derived from Triassic rocks. From the Serravallian on, the area experienced a horizontal maximum compression with a rotation of the maximum stress axis from E-W to N-S.
Geological setting
The resulting deformation gave rise to a strike-slip fault whose evolution is characterized progressively by three stages (see Figure 4): (i) stepover/releasing bend with a dextral motion of blocks; (ii) very close to pure horizontal compression; and (iii) restraining bend with a sinistral movement of blocks.
In particular, after an incipient fracturing stage, faults generated a pull-apart basin with terraced sidewall fault and graben subzones developed in the context of a dextral stepover during the lower part of late Miocene p.p. The occurrence of Triassic shales and evaporites played a fundamental role in the tectonic evolution of the study area. The salty material flowed along faults during this stage generating salt walls in root zones and salt push-up structures at the surface. During the purely compressive stage (middle part of late Miocene p.p.) the salt walls were squeezed to form extrusive mushroom-like structures. The large amount of clayish and salty material that surfaced was rapidly eroded and deposited into the basin, generating prograding fan clinoforms. The occurrence of shales and evaporites (both in the margins of the basin and in the proper infilling) favored folding of basin deposits, faulting, and the formation of rising blocks. Later, in the last stage (upper part of late Miocene p.p.), the area was affected by sinistralrestraining conditions and faults must have bent to their current shape. The progressive folding of the basin and deformation of margins changed the supply points and finally caused the end of deposition and the beginning of the current erosive systems. On the basis of the interdisciplinary results, the Agost Basin can be considered a key case of the interference between salt tectonics and the evolution of strike-slip fault zones. The reconstructed model has been compared with several scaled sandbox analogical models and with some natural pull-apart basins.
Research supported by: Research Project CGL2016-75679-P, Spanish Ministry of Education and Science; Research Groups and Projects of the Generalitat Valenciana, Alicante University (CTMA-IGA); Research Group RNM 146, Junta de Andalucía; Grants from University of Urbino “Carlo Bo”, responsible M. Tramontana.
About this blog
This is a geological blog of a team of worker in the Westernmost Tethys which rocks are today found surrounding the Western Mediterranean basin (from the Gibraltar Strait to the Messina Strait-Sicily passage).
We are focus on the interaction of the two main continents of Africa and Europe and the microplates in between.
In this blog will comment our works, highlight the key point, illustrate our fieldwork and add new figures.
Figure of the Central Betics showing the metamorphic complexes and the neogene basins.
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