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  1. The tristate area of Iowa, Illinois, and Missouri contains some of the best-exposed Mississippian strata in the world, including the type area for the Mississippian subsystem, across a broad carbonate platform known as the Burlington shelf. Strata have been mapped as thinnest along the central middle shelf and thickening both up-ramp and down-ramp, forming a complex dumbbell-like stratigraphic pattern rather than a simple clinoform geometry thinning into the basin. Additionally, two significant hiatuses at the Devonian-Carboniferous boundary and Kinderhookian-Osagean boundary greatly complicate stratigraphic correlations across the region. As a result, the precise temporal relationships between strata deposited across the region remain uncertain.

    Two large biogeochemical events occurred during this interval that provide facies-independent chronostratigraphic tools: the Hangenberg event, which marks the Devonian-Carboniferous boundary, and the Kinderhookian-Osagean boundary event. To target these events, we collected 66 conodont samples and 1005 carbonate carbon isotope samples from three cores and three outcrops and integrated the results with existing data from key facies/depth transitions across the Burlington shelf. Our new data demonstrate a complex relationship among complementary stratigraphic thicknesses, where the Devonian-Carboniferous boundary interval is thin or absent in the up-ramp inner-shelf setting and preserved in a significantly expanded interval in the central to distal middle-shelf deposits of southeast Iowa and northeast Missouri. However, the overlying Kinderhookian-Osagean boundary interval is not preserved in this down-ramp setting but is preserved in significantly expanded strata in the up-ramp inner-shelf setting of central Iowa.

     
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    Free, publicly-accessible full text available September 20, 2024
  2. Collections digitization relies increasingly upon computational and data management resources that occasionally exceed the capacity of natural history collections and their managers and curators. Digitization of many tens of thousands of micropaleontological specimen slides, as evidenced by the effort presented here by the Indiana University Paleontology Collection, has been a concerted effort in adherence to the recommended practices of multifaceted aspects of collections management for both physical and digital collections resources. This presentation highlights the contributions of distributed cyberinfrastructure from the National Science Foundation-supported Extreme Science and Engineering Discovery Environment (XSEDE) for web-hosting of collections management system resources and distributed processing of millions of digital images and metadata records of specimens from our collections. The Indiana University Center for Biological Research Collections is currently hosting its instance of the Specify collections management system (CMS) on a virtual server hosted on Jetstream, the cloud service for on-demand computational resources as provisioned by XSEDE. This web-service allows the CMS to be flexibly hosted on the cloud with additional services that can be provisioned on an as-needed basis for generating and integrating digitized collections objects in both web-friendly and digital preservation contexts. On-demand computing resources can be used for the manipulation of digital images for automated file I/O, scripted renaming of files for adherence to file naming conventions, derivative generation, and backup to our local tape archive for digital disaster preparedness and long-term storage. Here, we will present our strategies for facilitating reproducible workflows for general collections digitization of the IUPC nomenclatorial types and figured specimens in addition to the gigapixel resolution photographs of our large collection of microfossils using our GIGAmacro system (e.g., this slide of conodonts). We aim to demonstrate the flexibility and nimbleness of cloud computing resources for replicating this, and other, workflows to enhance the findability, accessibility, interoperability, and reproducibility of the data and metadata contained within our collections. 
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