Comparative Taphonomy and Sedimentology of Small-Scale Mixed Carbonate/Siliciclastic Cycles: Synopsis of Phanerozoic Examples

Brett, Carlton E.; Allison, Peter A.; Hendy, Austin J.W.

doi:10.1007/978-90-481-8643-3_4

Cited by 7 publications

(9 citation statements)

References 145 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…14b). Nevertheless, the regular concentrations of shells, the thickness of shell beds, and evidence of sea-level rise upward through the stratigraphy of these shell beds are more likely the result of reduced sedimentation rate and condensation associated with high-frequency marine transgressions (e.g., Kidwell 1989;Brett 1995;Hendy et al 2006;Brett et al 2011).…”

Section: Sea-level Oscillationsmentioning

confidence: 98%

Neogene molluscs, shallow marine paleoenvironments, and chronostratigraphy of the Guajira Peninsula, Colombia

et al. 2015

Self Cite

View full text Add to dashboard Cite

The Neogene sedimentary fill of the Cocinetas Basin in northern Colombia preserves a rich record of marine invertebrates and can be analyzed in the context of a high-resolution stratigraphy and excellent chronostratigraphy. Molluscan fossils are highly diverse and often well preserved, offering a window into the rapidly changing paleoenvironments and biogeography of northern South America during parts of the Early to Middle Miocene and latest Pliocene to Pleistocene. Before the evolutionary and biogeographic implications of these fossils can be understood, however, their associated depositional environments and geologic ages must be determined. Here, we present preliminary results from paleoenvironmental, biostratigraphic, and strontium isotope chronostratigraphic analyses of sediments and fossils from the Uitpa, Jimol, Castilletes, and Ware formations found in Cocinetas Basin. The basal unit in the Neogene succession, the Uitpa Formation, comprises mudstones redeposited sandstones and molluscs typical of bathyal to outer shelf environments at its base. It is a shallowing-up sequence and is conformable with the overlying Jimol Formation, which comprises coarsegrained lithic calcarenite, coquina, and mudstone that represent a regressive-transgressive-regressive sequence. This sequence includes foreshore and transition zone through lower inner shelf environments, but generally poorly preserved invertebrate assemblages. The conformably overlying Castilletes Formation contains a varied suite of depositional environments with better-developed shell beds and thicker successions of intervening siltstone. A significant unconformity exists between the Castilletes Formation and the overlying Ware Formation, which represents a deltaic to coastal shoreface deposition environment, rich in shallow marine molluscs from a variety of ecotopes. Biostratigraphic assessment and strontium isotopic results from the Jimol and Castilletes formations indicate that these units contain fossils of latest Early Miocene through Middle Miocene age, while those of the Ware are approximately Late Pliocene in age. These results help to place the shallow marine assemblages of Cocinetas Basin into a wider geologic context that aids our understanding of how these faunas relate to the broader evolutionary and biogeographic history of the southern Caribbean during the Neogene. Additionally, the isotope dating and paleoecology of this fauna help to place cooccurring terrestrial and aquatic vertebrate assemblages into a local paleoenvironmental and chronostratigraphic framework.

show abstract

Section: Sea-level Oscillationsmentioning

confidence: 98%

Neogene molluscs, shallow marine paleoenvironments, and chronostratigraphy of the Guajira Peninsula, Colombia

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…7; Brett et al, 2011). This observation reflects a bias; although obtaining fossils from the limestone requires cracking of relatively indurated beds, the trilobites within these beds are remarkable for their random orientations and complete lack of compaction.…”

Section: Devonian Trilobite Bedsmentioning

confidence: 85%

“…These beds are well known in two areas: the region of Jebel Issimour where the primary beds are quarried so deeply that they form prominent notches that can be traced for kilometers in the cliff face and near Foum Zguid (see Chatterton et al, 2006;Chatterton and Gibb, 2010), and much less well known from the region near Assa in southwestern Morocco (Becker et al, 2004a(Becker et al, , 2004bJansen et al, 2004;Brett et al, 2011Brett et al, , 2012.…”

Section: Devonian Trilobite Bedsmentioning

confidence: 95%

“…Upper Ordovician Collingwood Shale.-The Collingwood Member of the Lindsay Formation is a 7-10-m-thick interval in southern Ontario that displays distinctly rhythmic bedding of decimeter-scale, micritic concretionary limestone and medium to dark-gray and black organic-rich shale and calcareous mudstone (marl) (Brett et al, , 2011. Individual rhythms have been traced in closely spaced outcrops and, more tentatively, in drill cores .…”

Section: Upper Ordovician Trilobite Bedsmentioning

confidence: 99%

“…A majority of the surveyed trilobite beds are developed in moderately calcareous facies and display alternations of medium-to dark-gray, fissile shale and decimeter-scale bands of argillaceous limestone ( Fig. 7; see Brett et al, 2011Brett et al, , 2012, for further discussion). These beds, especially in weathered outcrops, display a strikingly rhythmic aspect of alternating dark-and light-gray bands (Fig.…”

Section: Early Postburial and Diagenetic Overprint In Trilobite Bedsmentioning

confidence: 99%

See 2 more Smart Citations

Mid-Paleozoic Trilobite Lagerstatten: Models of Diagenetically Enhanced Obrution Deposits

Brett

Zambito

Hunda

et al. 2012

PALAIOS

View full text Add to dashboard Cite

Spectacular trilobite Lagerstätten occur in distinctive offshore calcareous mudstone facies through the Late Ordovician to Devonian, and reflect a combination of mass mortality or molting and burial, coupled with early diagenetic enhancement. Evidence indicates two distinct modes of burial, Type I and II assemblages, which show evidence for burial without or with seafloor disturbance, respectively. Type I assemblages suggest rapid (hours to days), but not instantaneous burial, without bottom disruption, enabling preservation of in situ behavior, including mass aggregations and molt ensembles. Most occurrences contain bedding planes in which trilobites exhibit incipient disarticulation. These assemblages were buried by cascades of flocculated sediment from hypopycnal, detached flows. Type II assemblages show well-articulated, enrolled, semi-enrolled, and outstretched trilobites in varied orientations relative to bedding. In such cases, bottom flows and seafloor disruption by storm or seismic disturbances in shallow waters suspended large amounts of flocculated muds as viscous slurries, which developed into hyperpycnal flows that entrained carcasses of trilobites and other organisms. In many cases, both Type I and II obrution was followed by additional sedimentation, geochemical zones moved upward through the sediment column, and there was little tendency to form diagenetic overprints. Alternatively, if burial was followed by an interval of sediment starvation, the sediments were bioturbated and very early diagenetic mineralization was superimposed, first, in rare cases, as mineralized soft parts in entombed carcasses, and later as pyritization of burrow linings. Development of the concretionary layers required more prolonged periods of stability of the sulfate reduction zone. Cementation of sediment shielded organism bodies from most or all effects of compaction. Thus, ironically, the best preservation of delicate remains required rapid burial, associated with mass mortality, and very low rates of background sedimentation following the event.

show abstract

Detecting detrital carbonate in shale successions - Relevance for evaluation of depositional setting and sequence stratigraphic interpretation

Schieber

Shao

2021

Marine and Petroleum Geology

View full text Add to dashboard Cite

Comparative Taphonomy and Sedimentology of Small-Scale Mixed Carbonate/Siliciclastic Cycles: Synopsis of Phanerozoic Examples

Cited by 7 publications

References 145 publications

Neogene molluscs, shallow marine paleoenvironments, and chronostratigraphy of the Guajira Peninsula, Colombia

Neogene molluscs, shallow marine paleoenvironments, and chronostratigraphy of the Guajira Peninsula, Colombia

Mid-Paleozoic Trilobite Lagerstatten: Models of Diagenetically Enhanced Obrution Deposits

Detecting detrital carbonate in shale successions - Relevance for evaluation of depositional setting and sequence stratigraphic interpretation

Contact Info

Product

Resources

About