DOI: 10.5061/dryad.2rbnzs7jn
title: Data from: Ontogenetic variability in crystallography and mosaicity of conodont apatite: Implications for microstructure, paleothermometry and geochemistry

description: X-ray diffraction data from Silurian conodonts belonging to various
 developmental stages of the species Dapsilodus obliquicostatus demonstrate
 changes in crystallography and degree of nanocrystallite ordering
 (mosaicity) in both hyaline and albid crown tissue. The exclusive use of a
 single species in this study, combined with systematic testing of each
 element type at multiple locations, provided insight into microstructural
 and crystallographic differentiation between element position (Sa, Sb-c,
 M) as well as between juveniles and adults. A relative increase in the
 unit cell dimensions of the a-axis/c-axis ratio of nanocrystallites during
 growth was apparent in areas demonstrating single-crystal behavior but no
 such relationship was seen in dominantly polycrystalline areas. Systematic
 variations in mosaicity were identified, with mosaicity (as a proxy for
 disorder) increasing during growth, as well as along elements from tip to
 base. These results provide potential insight into the integrity of
 conodont apatite as a recorder of paleoseawater chemistry, as well as
 demonstrate the need to consider the influence of ontogeny and element
 position on the use of conodonts in paleothermometry and geochemical
 investigations.    
description: X-ray diffraction
 experiments were carried out in a Bruker D8 Quest single crystal X-ray
 diffractometer equipped with a CMOS area detector that allows diffraction
 pattern analysis of both single-crystalline and polycrystalline material.
 Irradiation of samples occurred through a microfocus Mo Kα (λ = 0.7107 Å)
 X-ray source with a beam diameter of 120 μm, which is suitable to analyze
 multiple positions along each specimen. Depending on the size of the
 sample, three to six zones were analyzed along the length of each element.
 In a typical experiment, conodont elements were coated with mineral oil,
 then attached on top of MiTeGen Dual-Thickness MicroLoop in a vertical
 position.  The sample was placed on the three-circle goniometer and the
 position of the X-ray beam was chosen using the microscope camera. X-ray
 diffraction data associated with each position were collected in
 reflection mode by varying the Φ angle while keeping the other angles
 fixed (2θ=0<sup>o</sup>, ω=0<sup>o</sup> and
 χ=54.74<sup>ᵒ</sup>). An eight- to eleven-second exposure time
 was needed for analyzing albid and hyaline material and a 20-30 second
 exposure time was needed for the basal cavity. Alignment of the
 diffractrometer was calibrated using the standard YLID crystal provided by
 Bruker AXS.
description: This DATSETNAMEreadme.txt file was generated on 2020-06-30 by
 Mohammad Shohel GENERAL INFORMATION
 1. Title of Dataset: Ontogenetic variability in crystallography
 and mosaicity of conodont apatite: Implications for microstructure,
 paleothermometry and geochemistry 2. Author
 Information<br>     A. Principal Investigator Contact
 Information<br>         Name: Tori Z. Forbes<br>       
  Institution: University of Iowa<br>         Address: Department of
 Chemistry, University of Iowa, Iowa City, IA 52242, USA<br>       
  Email: tori-forbes@uiowa.edu     B. Associate or
 Co-investigator Contact Information<br>         Name: Bradley D.
 Cramer<br>         Institution: University of Iowa<br>       
  Address: Department of Earth and Environmental Sciences, University of
 Iowa, Iowa City, IA 52242, USA<br>         Email:
 bradley-cramer@uiowa.edu     C. Alternate Contact
 Information<br>         Name: <br>       
  Institution: <br>         Address: <br>       
  Email:  3. Date of data collection (single date,
 range, approximate date) : 2016-2018 4. Geographic
 location of data collection : Department of Chemistry, University of Iowa,
 Iowa City, IA 52242, USA 5. Information about funding
 sources that supported the collection of the data: American Chemical
 Society- Petroleum Research Fund (ACS-PRF) Grant # ND-18485100
 <br> SHARING/ACCESS INFORMATION 1.
 Licenses/restrictions placed on the data:  2. Links to
 publications that cite or use the data:  Shohel M,
 McAdams NEB,<br> Cramer BD, Forbes TZ. 2020 Ontogenetic
 variability<br> in crystallography and mosaicity of
 conodont<br> apatite: implications for microstructure,<br>
 palaeothermometry and geochemistry. R. Soc. Open<br> Sci. 7:
 200322.<br> http://dx.doi.org/10.1098/rsos.200322
 3. Links to other publicly accessible locations of the
 data:  4. Links/relationships to ancillary data
 sets:  5. Was data derived from another source?
 yes/no<br>     A. If yes, list source(s):  6.
 Recommended citation for this dataset:  Shohel M,
 McAdams NEB,<br> Cramer BD, Forbes TZ. 2020 Ontogenetic
 variability<br> in crystallography and mosaicity of
 conodont<br> apatite: implications for microstructure,<br>
 palaeothermometry and geochemistry. R. Soc. Open<br> Sci. 7:
 200322.<br> http://dx.doi.org/10.1098/rsos.200322
 <br> DATA & FILE OVERVIEW 1.
 File List: <br> Sa-1, Sa-2, Sa-3, Sa-4, Sa-5: Folders that conatain
 diffrcation frames of 5 Sa elements of conodont microfossils. Inside those
 folder there are subfolder with end "T" and a "number"
 (e.g. T1). The number indicates specific zone that was anlysed. and the
 subfolder contain diffraction frames of that zone.<br> Sbc-1, Sbc-2,
 Sbc-3, Sbc-4, Sbc-5: Folders that conatain X-ray diffrcation frames of 5
 Sbc elements of conodont microfossils. Inside those folder there are
 subfolder with end "T" and a "number" (e.g. T1). The
 number indicates specific zone that was anlysed. and the subfolder contain
 diffraction frames of that zone.<br> M-1, M-2, M-3, M-4: Folders
 that conatain X-ray diffrcation frames of 5 Sa elements of conodont
 microfossils. Inside those folder there are subfolder with end
 "T" and a "number" (e.g. T1). The number indicates
 specific zone that was anlysed. and the subfolder contain diffraction
 frames of that zone.<br> Basal split: Folder contains X-ray
 diffraction frames of split basal body.  2.
 Relationship between files, if important:  3.
 Additional related data collected that was not included in the current
 data package:  4. Are there multiple versions of the
 dataset? yes/no<br>     A. If yes, name of file(s) that was
 updated: <br>         i. Why was the file updated? <br>       
  ii. When was the file updated?  <br>
 METHODOLOGICAL INFORMATION 1. Description of methods
 used for collection/generation of data: <br> X-ray diffraction
 experiments were carried out in a Bruker D8 Quest single crystal X-ray
 diffractometer equipped with a CMOS area detector that allows diffraction
 pattern analysis of both single-crystalline and polycrystalline material.
 Irradiation of samples occurred through a microfocus Mo Kα (λ = 0.7107 Å)
 X-ray source with a beam diameter of 120 μm, which is suitable to analyze
 multiple positions along each specimen. Depending on the size of the
 sample, three to six zones were analyzed along the length of each element.
 In a typical experiment, conodont elements were coated with mineral oil,
 then attached on top of MiTeGen Dual-Thickness MicroLoop in a vertical
 position.  The sample was placed on the three-circle goniometer and the
 position of the X-ray beam was chosen using the microscope camera. X-ray
 diffraction data associated with each position were collected in
 reflection mode by varying the Φ angle while keeping the other angles
 fixed (2θ=0o, ω=0o and χ=54.74ᵒ). An eight- to eleven-second exposure time
 was needed for analyzing albid and hyaline material and a 20-30 second
 exposure time was needed for the basal cavity. Alignment of the
 diffractrometer was calibrated using the standard YLID crystal provided by
 Bruker AXS. 2. Methods for processing the
 data: <br> The submitted data is in sfrm format which in standard
 for single crystal diffraction frames.  3. Instrument-
 or software-specific information needed to interpret the data: <br>
 Any single crystal X-ray diffraction data processing software that are
 capable of reading sfrm file can be used to interpret the data. We used
 APEX-3 software provided by Bruker AXS, USA. 
 <br> 4. Standards and calibration information, if
 appropriate: When analyzing Debye ring, the detector distance, swing
 angle, and beam center were calibrated by comparing the 2θ angles and
 detector position of a polycrystalline biomimetic<br> fluorapatite
 standard produced in the University of Iowa Department of
 Chemistry 5. Environmental/experimental conditions: The
 diffraction experiment was carried out at 100K.  6.
 Describe any quality-assurance procedures performed on the data: Alignment
 of the diffractrometer was calibrated using the standard YLID crystal
 provided by Bruker AXS.<br>