Synopses & Reviews
Synopsis
This book presents the first overview of the Toarcian Oceanic Anoxic Event in the southern Iberian paleomargin, in the western Tethys. The study of catastrophic events that affected the ecosystems in the past is of great interest, because it offers the possibility of establishing models that can be applied to current and future environmental changes. The book provides comprehensive information on the changes in marine ecosystems in connection with a global massive extinction, the Early Toarcian, and with the deposition of black shales, global warming and a disruption of the carbon cycle.
In addition, the book describes the incidence of this event in this part of the Tethys close to the connection with the Protoatlantic, the Hispanic Corridor. Special attention is paid to sedimentological and ichnological aspects, fossil content (macroscopic and microscopic), and geochemistry. It also presents the facies changes related to fragmentation of the shelf and the evolution to hemipel
agic troughs and swells in this paleomargin. Lastly, it characterizes this anoxic event in under-researched outcrops from southern Spain and compares the findings with those in well-known sections from northern and central Europe.
This book offers a unique resource for all researchers interested in the Toarcian Oceanic Anoxic Event, but also in oceanic anoxic events that occurred during the Mesozoic in general, because of their similarity to recent climatic changes.
Synopsis
- Introduction
1.1. The Toarcian Oceanic Anoxic Event
1.2. The Betic Cordillera
1.3. The lower Jurassic from the epeiric platforms
1.4. Geological setting of the reference sections
- External Subbetic outcrops
3.1. Fuente Vidriera section
3.1.1. Mineralogy
3.1.2. Trace fossils
3.1.3. Foraminiferal and ostracod assemblages
3.1.4. Stable isotopes
3.1.5. Geochemical proxies
3.1.6. Interpretation
3.1.6.1. The T-OAE record from Fuente Vidriera section
3.1.6.2. The negative carbon isotopic excursion
3.1.6.3. Role of water stagnation vs. productivity
3.2. Cueva del Agua section
3.2.1. Facies and microfacies
3.2.2. Microfossil assemblages
3.2.3. Geochemistry
3.2.4. Interpretation
3.2.4.1. Dignification of facies and microfacies
3.2.4.2. Organic matter and sea-bottom oxygenation
3.2.4.3.
Isotopic fluctuations and environmental changes
3.3. La Cerradura section
3.3.1. Macroinvertebrates
3.3.2. Trace fossils
3.3.3. Calcareous nannofossils
3.3.4. Geochemistry
3.3.5. Interpretation
3.3.5.1. Pre-biotic crisis phase
3.3.5.2. T-OAE biotic crisis phase
3.3.5.3. Recovery phase
4. Middle Subbetic outcrops
4.1. Iznalloz section
4.1.1. Ammonite biostratigraphy
4.1.2. Lithofacies and microfacies
4.1.3. Microfossil assemblage
4.1.4. Trace fossils
4.1.5. Interpretation
4.1.5.1. Origin of sediment and lithofacies
4.1.5.2. Oxygenation
4.1.5.3. Nutrient content
4.1.5.4. Palaeoenvironmental reconstruction
4.2. Arroyo Mingarr n section
4.2.1. Lithofacies and microfacies
4.2.2. Calcareous nannofossils
4.2.3. Interpretation
4.2.3.1. The Toarcian Ammonitico Rosso context
4.3. Poloria se
ction
4.3.1. Facies and microfacies
4.3.2. Stable isotopes
4.3.3. Interpretation
5. The incidence of the T-OAE in the South Iberian Palaeomargin
6. References
Synopsis
Enriches understanding of the T-OAE giving relevant information from an area poorly studied, the south Iberian palaeomargin
Includes six reference sections where the T-OAE is recorded with very different features and we show different approaches (and methodologies) for understanding the incidence of this event
Presents the integrated analysis of geochemistry, ichnofossils and microfossil assemblages for understanding the environmental conditions before the anoxic event, during the biotic crisis and the subsequent recovery
Includes numerous figures that enrich the text by illustrating the results as well as the discussion/interpretation