Facies analysis and correlation of high-order sequences in middle-outer ramp successions: variations in exported carbonate on basin-wide δ13Ccarb (Kimmeridgian, NE Spain)

Bádenas, B.; Aurell, M.; Gröcke, D.R.

Abstract

Carbonate mud that accumulated in the deep parts of a late Kimmeridgian carbonate ramp (Iberian Basin, NE Spain) was partly derived by resedimentation from shallow water production areas. High-frequency sea-level changes, probably driven by climatic changes in tune with precession and short-eccentricity cycles, affected carbonate production and the amount of exported sediment. Facies analysis and correlation of three outcrops located in middle and outer ramp settings allows a comparison of high-order sequences (bundles of beds and sets of bundles) across a ramp transect and an assessment of the carbonate factory. Analysis of the storm deposits found in middle ramp settings identifies deepening to shallowing high-frequency cycles based on the level of exported carbonate. In outer ramp areas, many of the bundles exhibit a thinning trend, indicating a progressive decrease of carbonate production and hence, carbonate export during periods of high-frequency sea-level rise. δ13Ccarb values show a gradual increase through the studied long-term transgressive interval ranging from 1·5‰ to 2·8‰. Within this long-term evolutionary trend, short-term δ13Ccarb fluctuations occur that correspond with some of the high-order cycles defined from sedimentary facies analysis. These short-term δ13Ccarb shifts are interpreted as shifts in carbonate export from shallow reef regions to the outer ramp. A consequence of this study is that variation in δ13Ccarb can be used for correlation in outer ramp successions, at least on a basin-wide scale.

Citation

Bádenas, B., Aurell, M., & Gröcke, D. (2005). Facies analysis and correlation of high-order sequences in middle-outer ramp successions: variations in exported carbonate on basin-wide δ13Ccarb (Kimmeridgian, NE Spain). Sedimentology, 52(6), 1253-1275. https://doi.org/10.1111/j.1365-3091.2005.00740.x

• Journal Article Type: Article
• Publication Date: Dec 1, 2005
• Deposit Date: Jun 4, 2010
• Journal: Sedimentology
• Electronic ISSN: 1365-3091
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 52
• Issue: 6
• Pages: 1253-1275
• DOI: https://doi.org/10.1111/j.1365-3091.2005.00740.x
• Keywords: Carbon isotopes, Carbonate ramp, Cyclicity, Sea-level, Kimmeridgian, Jurassic.
• Public URL: https://durham-repository.worktribe.com/output/1543818