Evolution of a Late Oxfordian: early Kimmeridgian carbonate platform, French Jura Mountains

Nicolas Olivier,Elsa Cariou,Pierre Hantzpergue

doi:10.1007/s00015-015-0189-9

Abstract

A detailed facies analysis and interpretation of the evolution of depositional environments along a north–south transect of the Late Oxfordian—Early Kimmeridgian French Jura carbonate platform highlights hierarchically stacked depositional sequences. The identified small- and medium-scale depositional sequences are matched with the precise cyclostratigraphic framework initially established for the Swiss Jura platform. The superimposition of a long-term (2nd order) sea-level rise with long (400 kyr) eccentricity cycles explains most of the French Jura platform architecture. During the Bimammatum and Planula zones, the climate became progressively warmer and more arid, allowing enhanced carbonate production. This resulted in a strong progradation of the French Jura platform that progressively evolved from a ramp to an oolitic rimmed shelf. A brief interval characterized by a more humid climate during the upper Bimammatum Zone caused an increase in siliciclastic and nutrient input, leading to a reduction in carbonate production and strong retrogradation of the platform. During the Platynota and lower Hypselocyclum zones, the shallow inner shelf carbonate production once more exceeded the accommodation, leading to a general aggradation of the platform. From the upper Hypselocyclum Zone, with a more humid climate, the carbonate production did not outweigh the accommodation creation and the platform evolved to a flat-topped shelf. Thus, sea-level changes and climatic conditions (temperature and humidity) are the key factors controlling the nature of the sedimentation and the depositional profile of the French Jura platform during the Late Oxfordian—Early Kimmeridgian.

Highlights

The Late Jurassic was a prolific Epoch for carbonate production and widespread carbonate platform construction (Kiessling et al 2003; Leinfelder et al 2002)
During the Bimammatum and Planula zones, the climate became progressively warmer and more arid, allowing enhanced carbonate production. This resulted in a strong progradation of the French Jura platform that progressively evolved from a ramp to an oolitic rimmed shelf
Several recent studies indicate Late Jurassic climate variations in shallow platform carbonates with short-term sea surface temperature changes in the northwestern Tethys (Dromart et al 2003a, b; Carpentier et al 2006; Brigaud et al 2008; Donnadieu et al 2011; Dera et al 2011)

Summary

Introduction

The Late Jurassic was a prolific Epoch for carbonate production and widespread carbonate platform construction (Kiessling et al 2003; Leinfelder et al 2002). The growth and demise of these carbonate platforms occurred in various climatic, eustatic and tectonic contexts (Pittet and Strasser 1998; Pittet et al 2000; Jank et al 2006a; Carpentier et al 2006, 2007). These ‘carbonate factories’ were controlled by numerous environmental parameters such as water depth, light, nutrient supply, temperature, salinity, hydrodynamic processes, and oxygenation (Lees 1975; Wright and Burchette 1996; Halfar et al 2006). Several recent studies indicate Late Jurassic climate variations in shallow platform carbonates with short-term sea surface temperature changes in the northwestern Tethys (Dromart et al 2003a, b; Carpentier et al 2006; Brigaud et al 2008; Donnadieu et al 2011; Dera et al 2011)

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Conclusion