Physical Sciences and Mathematics Commons^™

Integrating Bio-, Chemo-, Chrono-, Gamma-Ray, Litho-, And Sequence Stratigraphy In The Upper Cambrian And Lower Ordovician: Progress Toward A Comprehensive Stratigraphic Framework, James Miller, Benjamin Dattilo, Raymond Ethington, Kevin Evans, Rebecca Freeman, James Loch, John Repetski, Robert Ripperdan, Anthony Runkel, John Taylor

Benjamin F. Dattilo

Chronostratigraphic classification of the Laurentian Upper Cambrian and Lower Ordovician is based on strata in Utah, Nevada, Missouri, Minnesota, Wisconsin, and Alberta. Biozonations are based on strata there as well as in Texas and Oklahoma. Regional trilobite zonations vary somewhat because of facies influence and periods of regional endemism; the zonation is quite different in slope deposits. Conodont zonation begins in the middle Upper Cambrian; many taxa occur in a variety of facies and are cosmopolitan, so zones can be correlated across Laurentia and globally. Calcitic brachiopod zones established in Oklahoma have been identified in other areas where faunas have …

Revising Rafinesquina: New Insights On A Familiar Fossil., Benjamin Dattilo

Benjamin F. Dattilo

No abstract provided.

The Lower Ordovician Fillmore Formation Of Western Utah: Storm-Dominated Sedimentation On A Passive Margin., Benjamin Dattilo

Benjamin F. Dattilo

No abstract provided.

Fine-Scale Lithologic Variations In Late Ordovician (Katian) Pertidal Depositions Of The Kentucky Bluegrass Suggest Sea-Level Fluctuations As The Primary Mechanism For Type Cincinnatian Meter-Scale Cycles., Sasha Mosser, Thomas Schramm, Benjamin Dattilo, Carlton Brett, Rebecca Freeman, Michael Blair

Benjamin F. Dattilo

Late Ordovician peritidal facies of central Kentucky are laterally equivalent to cyclic subtidal facies of the Cincinnati region but correlation details, and causes of cyclicity are poorly understood. If type Cincinnatian shale-limestone (meter scale) cycles were driven by sea-level fluctuations then equivalent peritidal facies should be cyclic. Likewise, the same magnitude of base level change should result in greater environmental variability in these shallow facies. If cycles are of Milankovitch origin, it should be reflected in cycle duration. We attempt to test these predictions by examining litho, sequence, and macro-biostratigraphic evidence at Point Leavell, KY and other localities. Exposures at …

Layer-Cake Stratigraphy Versus Facies Mosaics In The Cincinnati Ordovician: What Is The Bedding Scale Structure Of The Stratigraphic Record?, Benjamin Dattilo

Benjamin F. Dattilo

No abstract provided.

The Great American Carbonate Bank In The Miogeocline Of Western Central Utah: Tectonic Influences On Sedimentation., James Miller, Kevin Evans, Benjamin Dattilo

Benjamin F. Dattilo

No abstract provided.

Gape, Feeding Currents And Valve Snapping In Thecidellina Meyeri From Curaçao, Netherlands Antilles: Biomechanical Analogue For Trace-Making Paleozoic Strophomenates?, Benjamin Dattilo, Tanya Del Valle, David Meyer, Aaron Morse

Benjamin F. Dattilo

The ability of Ordovician strophomenates Sowerbyella and Rafinesquina to move sediment and create moat-like depressions has led to questions about mechanisms. Anatomical studies suggest a gape of more than 45°, likely critical to trace-making abilities. Strophomenates are extinct, but thecidellinids are reasonably good analogues; they also gape widely and have a similar lophophore structure. They differ in their small size, 3 - 5 mm, lack of concavo-convex form, and by pedicle valve cementation. Nevertheless, their physiology could illuminate biomechanical constraints on strophomenate-sediment interactions. For this study, we analyzed 1 hour of video showing 30+ specimens collected with the fragment of …

The Brachiopod Trap: What Their Oldest (Upper Ordovician, Ohio) Failed Escape Burrows Tell Us About The Evolution Of Burrowing In Lingulids, Rebecca Freeman, Benjamin Dattilo, Aaron Morse, Michael Blair, Bryan Utesch, Steve Felton, John Pojeta

Benjamin F. Dattilo

Infaunal organisms living in shallow marine settings are vulnerable to exhumation during storms or entombment by storm-deposited sediments. Cambrian­–Early Ordovician lingulids included epifaunal as well as possible infaunal forms. However, many epifaunal forms became extinct during the Middle Ordovician, and Late Ordovician lingulids were similar in their infaunal habits and marginal habitats. Modern infaunal lingulids are able to reorient themselves after burial in sediments, but it is unclear when this ability evolved. Initial burrowing of juvenile lingulids, as well as re-burrowing of exhumed modern lingulids involves digging downwards and then back up in a u-shape, but successful escape burrowing involves …

Tempestites In A Teapot? Condensation-Generated Shell Beds In The Upper Ordovician, Cincinnati Arch, Usa, Benjamin F. Dattilo

Benjamin F. Dattilo

Skeletal concentrations in mudstones may represent local facies produced by storm winnowing in shallow water, or time-specific deposits related to intervals of diminished sediment supply. Upper Ordovician (Katian) of the Cincinnati region is a mixed siliciclastic-carbonate succession including meter-scale cycles containing a shelly limestone-dominated phase and a mudstone-dominated phase.

The “tempestite proximality model” asserts that shell-rich intervals originated by winnowing of mud from undifferentiated fair-weather deposits. Thus shell beds are construed as tempestites, while interbedded mudstones represent either fair-weather or bypassed mud. Meter-scale cycles are attributed to sea-level fluctuation or varying storm intensity.

Alternatively, the “episodic starvation model” argues, on …