The Down-dip Preferential Sequence Record of Orbital Cycles in Greenhouse Carbonate Ramps

Astronomical Pacing of Middle Eocene Sea‐Level Fluctuations: Inferences From Shallow‐Water Carbonate Ramp Deposits

“…The age model with a resolution of long eccentricity (0.405 Myr) is in accord with the concept that cyclic sequences of shallow marine carbonate platforms from the Hothouse worlds document accretionary dynamics paced by insolation driven cycles of sea level in the Milankovitch frequency band (Laskar et al, 2011;Read et al, 1995). Specifically, we observe correspondence between third order depositional sequences with the very long eccentricity cycle (2.4 Myr), factors which had been predicted earlier to be characteristically expressed in the shallow portions of carbonate platforms and ramps from the Hothouse geological periods (Bádenas & Aurell, 2018) and that we show now for the middle Eocene of PB.…”

“…A uniform duration of the elementary sequences associated with the long eccentricity cycle of 0.405 Myr is a likely scenario, in particular, as this cycle is present in many sedimentary records and the least influenced on the long-run by chaotic diffusion present in the Solar System than shorter periods around 0.1 Myr (Laskar et al, 2011). Eccentricity-dominated cyclicity has been described to occur preferentially in the shallowest segments of carbonate ramps systems of some Mesozoic Hothouse climates (Bádenas & Aurell, 2018), that we now identify as the primary pacemaker in our data of the shallow PB ramp (Figure 3 and Figure S3 in Supporting Information S1). Remarkably, most prominent of the long-term modulation of the 0.405 Myr component is the very long eccentricity related ∼2.4 Myr cycle that is a characteristic of the deep-sea record of the entire Cenozoic (Franceschi et al, 2015;Kocken et al, 2019;Laskar et al, 2011).…”

Orbital cycles, differential subsidence and internal factors controlling the high-frequency sequence architecture in a Sinemurian shallow carbonate platform (Mallorca island, Spain)

“…9). This case conforms the proposed model by Bádenas and Aurell (2018) of low preservation potential of short eccentricity-related medium-scale sequences in shallow settings with low accumulation rates, due to the combination of low accommodation and effectiveness of the erosional processes in these settings. Also the definition of medium-scale sequences may be obscured (amalgamated) in areas without facies variability and frequent presence of erosional surfaces, like in the case of the inter-supratidal dominated S´Heretat section (Fig.…”

“…The concept of high-frequency sequences of different scales is used here from a descriptive point of view, which implies a hierarchy of sequences in which smaller J o u r n a l P r e -p r o o f 9 sequences stack in longer sequences (e.g., Bádenas and Aurell, 2018). The identification of the different scale depositional sequences is based on two main criteria (e.g., Bosence et al, 2009;Bádenas et al, 2010): (1) the recognition of sequence boundaries, represented by discontinuity surfaces reflecting breaks in sedimentation, and (2) the vertical facies trends within sequences.…”

A mud-dominated coastal plain to lagoon with emerged carbonate mudbanks: The imprint of low-amplitude sea level cycles (mid-Upper Cretaceous, South Iberian Ramp)

“…In the case studied here, log correlation points out to a possible merging or amalgamation of 100 ky-parasequences in less subsident areas. Presence of 2 o 3 parasequences in sequence 5 dominated by shallowest facies (ponds and mudbanks belt facies association B and vegetated coastal plain facies association C) also conforms to the model of Bádenas and Aurell (2018) of lower preservation potential of 100 ky-related sequences in shallow settings with low accumulation rates, due to the combination of low accommodation and internal factors of sediment production and erosion/accumulation.…”