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Peter Blum, October 2022 (another update)

Purpose of stratigraphic correlation on the JOIDES Resolution

Shipboard (during expedition)

  1. Minimize coring gaps
    1. Provide rapid correlations when drilling multiple holes to ensure core gaps in one hole are covered by core in another hole.
    2. Use of the secondary core logger (Special task multisensor logger, STMSL) in addition to the primary logger (whole-round multi-sensor logger, WRMSL) is highly recommended.
    3. Requires effective real-time communication with the "core tech" from the drilling crew to achieve drilling depth corrections in time to mitigate coring gaps.
  2. Construct core composite depth scale below seafloor (CCSF)
    1. Provide a first order correlation of all cores from multiple holes by depth shifting (affine translation without scaling)
  3. Construct sampling splice
    1. Provide a primary spliced section, consisting of core intervals from multiple holes.
    2. The primary splice shall represents as much as possible of the stratigraphic section at a drill site.
    3. Sample locations in the curated core (core depth below seafloor, method A, CSF-A) can be mapped easily to the splice using the core offsets that define the CCSF depth scale.

Typically on shore (post-expedition - optional)

  • Map non-splice intervals into the the primary splice (includes stretching and squeezing).
  • Scale the CCSF depth scale, and/or a modified/mapped variant of it, to other depth scale(s) to match the drillers depth below seafloor (DSF) scale or a wireline logging depth scale.
  • Astronomical tuning of the final depth scale.

Workflow and tools

  • The workflow for the correlation of stratigraphic records obtained from scientific ocean drilling cores requires multiple applications.
  • The workflow summarized here is primarily for the shipboard tasks. However, most of it can be done on shore before and/or after an expedition.


Table 1. Tasks and tools for stratigraphic correlation on and off the JOIDES Resolution.

TaskWorkflowData typesTool on JRApplicable on shore?User guide
Prepare data for correlationNon-image data

Correlation Downloader

Not a this time. Use already prepared data or ask JRSO staff for help.
Image dataLORE (LIMS Online Reports)Yes
ImageRedux: cull and resample images ImageResample (R script)Yes
Correlate: shift cores and splice core segmentsAll non-image and image data Correlator appYes
Load shift offsets and splice interval data to the LIMS database

Affine tables

Splice interval tables

SCORS Uploader and ManagerYes but requires credentials to write to the LIMS database (and approval by project manager)
Download data with CCSF (core composite depth below seafloor) depthsAll data accessible from the LIMS databaseLORE (LIMS Online Reports)Yes

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Figure 1-1. Stratigraphic correlation support (SCORS) workflow and tools.

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Correlation Downloader

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