DOI: 10.5061/dryad.z8w9ghxr2
title: Data from: 283,821 concretions, how do you measure the Mazon Creek? Assessing the paleoenvironmental and taphonomic nature of the Braidwood and Essex assemblages

description: The Mazon Creek Lagerstätte (late Carboniferous Period, Moscovian Stage;
 Illinois, USA) captures a diverse view of ecosystems in delta-influenced
 coastal settings through exceptional preservation of soft tissues in
 siderite concretions. The generally accepted paradigm of the Mazon Creek
 biota has been that of an inferred paleoenvironmental divide between what
 have been termed the Braidwood and Essex assemblages, wherein the former
 represents a freshwater ecosystem with terrestrial input and the latter a
 marine-influenced prodelta setting with abundant cnidarians, bivalves,
 worm phyla, and diverse arthropods. Here, we revisit the paleoecology of
 the Mazon Creek biota by analyzing data from nearly 300,000 concretions
 from 270 locations with complementary multivariate ordinations. Rather
 than a homogenization of ecological communities, our results show the
 Braidwood assemblage as a legitimate shoreward community and provide
 evidence for further subdivision of the Essex assemblage into two distinct
 subassemblages, termed here the Will-Essex and Kankakee-Essex. The
 Will-Essex represents a benthos dominated by clams and trace fossils along
 the transition between nearshore and offshore deposits. The Kankakee-Essex
 is dominated by cnidarians, presenting an ecosystem approaching the
 geographic margin of this taphonomic window. These new insights also allow
 a refined taphonomic model, wherein recalcitrant tissues of Braidwood
 organisms were subject to rapid burial rates while organisms of the Essex
 assemblage typically had more labile tissues and were subject to slower
 burial rates. Consequently, we hypothesize that the Braidwood fossils
 should record more complete preservation than the Essex, which was exposed
 for longer periods of aerobic decomposition. This is supported by a higher
 proportion of non-fossiliferous concretions in the Essex than in the
 Braidwood.
description: # 283,821 concretions, how do you measure the Mazon Creek? Assessing the
 paleoenvironmental and taphonomic nature of the Braidwood and Essex
 assemblages Dataset DOI:
 [10.5061/dryad.z8w9ghxr2](10.5061/dryad.z8w9ghxr2) ## Description of the
 data and file structure The raw dataset from Baird et al. (1985) comprises
 286,953 concretions from 342 separate collections from the Mazon Creek
 Lagerstätte. These and other non-included samples and all available
 metadata are detailed in the Supplementary Online Materials (SOM),
 Appendix 1. Samples were collected from exposed mine dump surfaces in over
 270 locations, including 25 strip mines and more than 80 shaft mines
 (Baird et al. 1985). The complete data set comprises 229 original
 identification groups (IDs), whether taxonomic or otherwise, including
 some subgroupings, taphomorphs, or other distinct characterizations (e.g.,
 crushed bivalves vs. intact shells). IDs were originally coded by Baird as
 4-character abbreviations, which have been included and defined in the
 SOM, Appendix 2. The original concretion tally includes both fossiliferous
 (specimens hereafter) and non-fossiliferous concretions. The original
 ledgers from each included sample have been digitized and are appended in
 the SOM, Appendix 3. We revised the ID groupings by combining IDs that
 were confidently considered junior synonyms and/or taphomorphs. Further
 details are included in the supplementary tables of SOM, Appendix 2. We
 culled the raw dataset for multivariate ordination and diversity analyses
 by removing duds, poorly preserved specimens that could not be identified
 below the phylum level, problematica, samples with fewer than 50
 specimens, and taxa represented in only one sample. All pertinent
 datasheets, including both the raw data tally and the culled dataset used
 for statistical analyses, are included as supplementary online files in
 Microsoft Excel format. In addition, for each sample not removed, we
 analyzed the proportion of duds to explore emergent trends in fossil
 preservation. The accompanying Excel file includes the raw dataset from
 Baird et al. (1985), which comprises 283,821 concretions from 342 separate
 collections from the Mazon Creek Lagerstätte. These and other non-included
 samples and all available metadata are detailed in the associated PDF
 file. These files constitute the Supplementary Materials for Schiffbauer,
 Baird, and colleagues in Paleobiology. ### Files and variables #### File:
 Schiffbauer\_et\_al\_Paleobiology\_SOM\_Mazon\_Creek\_Data.xlsx
 **Description:** The tabulated and digitized raw dataset from Baird et al.
 (1985), comprising 283,821 concretions from 342 separate collections from
 the Mazon Creek Lagerstätte.  **Variables/abbreviations included in the
 raw dataset are as follows:** Sample = locality number as defined during
 Baird's original collections Grouping = assigned
 environmental/ecological characterization based on abundance of key taxa
 (Braidwood = freshwater-dominated taxa; Will = marine assemblage dominated
 by clams and traces; Kankakee = cnidarian-dominated marine assemblage)
 Lat & Long = Latitude and longitude, in decimal format NMDS1, NMDS2,
 NMDS3: These columns represent the coordinates of each sample along the
 first three axes of the Non-metric Multidimensional Scaling (NMDS)
 analysis. Clade: The taxonomic classification of the organism, such as
 "Fish," "Amphibian," or "Plants." Habitat:
 The environmental setting where the organism is typically found (e.g.,
 "Marine," "Freshwater," or "Terrestrial").
 Tissue: The biological material or anatomical part of the organism being
 studied All four-letter identifications = call IDs for taxa preserved.
 This extensive list includes:  87 animal
 taxa: ACAN, AICH, AMPH, ANMD, ARAC, ARTH, BELO, BLOB, CAEN, CBAR, CCYC, CCYZ, CESS, CFLE, CHOP, CKAL, CKEL, CMES, CMRS, COST, CPAL, CPEA, CPYG, CSYN, CTYR, CUND, EDMO, EGGS, ESSX, ETAC, EUCH, EUPR, FCRT, FCTN, FESC, FGIL, FISH, FMEG, FPAL, FRHB, FWCL, FXNT, HDEV, HFTR, HOLT, INSC, KOTT, LIMU, LING, MBCR, MCEP, MCHT, MDUN, MEUP, MHTW, MLIM, MSCZ, MSOL, MSTR,  MUND, MYAL, NCYC, OCTO, PECT, PLXS, REGC, SHRP, TFTR, TMON, WBLN, WCAP, WDRY, WESC, WFAN, WFSH, WHYS, WILY, WNEM, WOLH,WPJM, WPLN, WPRI, WSJW, WSPR, WTTH, WUND, and YWHY 45 plant taxa: ALTH, ANNL, ASTR, LEPD,  LSTP,  LSTR, LYCO, NEUR, ODON, PAPH, PASO, PBRK, PCAL, PCON, PCRC, PCRD, PCRS, PCYC, PDRN, PECO, PFUN, PLEP, PLIN, PMAC, PMAR, PPIN, PSAR, PSEL, PSPR, PSTM,  PSUL, PTAE, PUND, SCBR, SEED, SPFR, SPHN, SPMG, SPRS, STIG, TCAR, TFBR, THAL, THRN, and TWSC 6 traces and other taxa: INCG, LETT, FCOP, TDPL, TPEL, and TRAL and 33 distinct descriptors for dud concretions: DBLB, DBLG, DBRN, DCOM, DDBL, DDGB, DDGF, DDGR, DFGR, DGBR, DGGR, DGRB, DGRF, DGRY, DLBG, DLBR, DLGH, DLGR, DMOT, DODD, DPYC, DREJ, DSBR, DSEP, DSGB, DSGR, DSLG, DSND, DSPH, DWTH, DYLB, DUDS, and DTOT We have provided extensive descriptions of each of the included taxa in Appendix 2 of the associated pdf, which includes Phylum, Class, and Genus designations for all animal taxa, as well as clade and habitat descriptors and any other relevant information. #### File: Schiffbauer\_et\_al\_Paleobiology\_SOM\_Mazon\_Creek.pdf **Description:** All metadata for the accompanying Excel data sheet as well as R markdown file for analyses used in Schiffbauer, Baird, and colleagues, Paleobiology.