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Figure 3.1-1. Example of a site folder with correlation data.

Special case

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: multiple files for the same data type

One of the primary objectives of stratigraphic correlation is to correlate section data from a new hole rapidly to the data from one or more previous holes to check if coring gaps in previous holes are recovered in the current hole. If coring gaps are not covered adequately due to the change in water depth (mostly due to tides, but also other environmental and operations factors), you want to provide relative coring offset (drill down interval) instructions to the drillers in near-real time.

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3.3. Import primary correlation data

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(Correlator will not allow you to import two files for the same data type). The new data type labels will stick in the data type list for future use in your session.
Now you can correlate the STMSL data rapidly acquired on critical sections from a new hole to the WRMSL data from previous holes using the TIE and SET methods.
 However, because Correlator was not designed to correlate different data types (usually makes no sense) the affine table currently only keeps track of the SHIFT core, with the assumption that the REF core tie point is from the same data type as the SHIFT tie point. An arrow can therefore not be drawn.

3.2. Import core section summary files

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3.3. Import core section images

Important:

• You must first import some primary correlation data (and the associated section summary data) before you can import images.
• The images must be JPEG format and in the order of ~200 kb each, which is sufficient for most correlation purposes. Try higher resolution at your own risk.

To import images:

• Right-click on Images in the Data Manager window.
• Navigate to your local data directory
• Select the folder containing the JPEG images you want to import and click import.

3.4. Load data for correlation

Basic procedure

To import data files:

• Right-click on the top item in the Data Manager window and select Add new data. 
  • A browser window opens that allows you to browse to the data files in your directory of choice (the path will stick for future imports and updates).
• Select a single file, or multiple files of the same type (and format). In the example in Fig. 3.2-1, magnetic susceptibility was selected for holes 361-U1476A and 361-U1476B.
  • The first 30 rows of data for each hole are displayed in the Generic Data tab (Fig. 3.2-1).
  • For commonly used data types, all column headers and column data should be automatically and correctly populated.
  • If that is not the case, you get a warning and must specify at least the Depth and the Data columns.
• Click the Import button at the bottom right and the focus returns to the Data Manager tab where a data summary line is added (Fig. 3.2-2).

Figure 3.2-1. The Import button opens in Generic Data window, where user may have to fill in the Data Type column by clicking on the header “Data Type” and selecting the appropriate item (in this case, Natural Gamma).

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Figure 3.2-2. Upon importing data, line items for each data type and each hole are added in the Data Manager tab . Note the Saved Tables folder created for affine and splice tables later created. Also note the Section Summaries folder automatically created and populated with the section summaries from the LIMS registry (more on that below).

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Special procedure

Correlator is trying to help you with file naming upon import. However, sometimes you may need to help Correlator learn the import data file, such as when you use correlation data from sources other than the JRSO Downloader app. One workflow, however, requires you to help a little even when using the Correlation Downloader. As described in section 3.1, you may have split the MS data into two files based on which core logger they were obtained from. What happens upon import depends to some degree on the file naming:

• If the files don't have 'susceptibility' in the file name, Correlator leaves the Data Type column in the Generic Data tab empty and will not allow you to import until you have specified a name.
• If both files have 'susceptibility' in the file name, Correlator with automatically use 'Susceptibility' as the data type for the first file, but it will not import the the second one because it already has a 'Susceptibility' file (Fig. 3.2-3).

Figure 3.2-3. Correlator does not allow import of multiple files it thinks are the same data type.

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To give unique data type names to you two MS files:

• Right-click on the Data Type column header.
• Use the Custom data type item from the choice list (Fig. 3.2-4).
  • For example, label the two files <SiteHole>_MS_WRMSL and <SiteHole>_MS_STMSL, respectively. 
  • The new data type labels will stick in the data type list for future use in your session.
• Proceed to selecting the appropriate items from the column menus for at least the following parameters, if they are not already auto-selected:
  • Section
  • TopOffset
  • BottomOffset
  • Depth
  • Data

Figure 3.2-4. Registering a data type not available in the Correlator choice list.

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Now you can correlate the STMSL data rapidly acquired on critical sections from a new hole to the WRMSL data from previous holes. However, because Correlator was not designed to correlate different data types (usually makes no sense) the affine table currently only keeps track of the SHIFT core (could be from either data file), with the assumption that the REF core tie point is from the same data type as the SHIFT tie point. Instead of an arrow from REF to SHIFT core, Correlator draws a line across the entire screen.

Adding more data

If you are correlating cores in real time, you will frequently add new data. 

To add more data:

• Go to the Data Manager window.
• If you  are returning from the Display window, you will get a message alerting you that the Display window will be cleared (Fig. 3.2-5).
• After you have imported the new data, you need to Load the data again anyway to get a current display. 

Figure 3.2-5. When a user adds new data to an existing, plotted data set, a warning is displayed to make the user ware that the display will be cleared with this action.

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Note: if you want to update the existing data, e.g., because you added another core to the hole file, use Update from the context menu.

3.3. Import section summary files

What is the section summary for?

Correlator needs top and bottom depths of sections to compute splice intervals correctly. The application maintains an internal table for that purpose. Three options exist due to the evolution of the program and its use in different environments.

Method 1 (not recommended on the JR)

In Correlator version 1, the tops and bottoms of sections were computed by Correlator based on the imported data, which often resulted in small and sometimes larger errors in splice tables. This functionality still exists in version 4 for backward compatibility, however, it is disabled by default in the Correlator > Preferences menu (Fig. 3.3-1). In situations where users do not have a section summary file for upload, they can enable the Infer Section Summary if none is provided feature and for each data file loaded (those with "Enable" on in the Data List), Correlator gathers the minimum and maximum depths of data points for each section. If multiple data types are loaded for a hole, all data types are considered and the minimum of minima offsets is used as the top of section and the maximum of maxima offsets is used for the bottom of section.

Figure 3.3-1. The Preferences menu.
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If this method is enabled, Correlator will give a message at the time of data import that the section summary was inferred from the data (Fig. 3.3-2).

Figure 3.3-2. Message if Correlator infers section boundaries from the data.

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Method 2 (standard method on the JR)

Starting with Correlator version 2, a section summary file is uploaded automatically when the user imports data to Correlator, if that section file exists in the same directory as the data file(s). This is the standard process on the JR because the Correlation Downloader application automatically downloads a section summary file from LIMS along with the data files, and also updates the section file along with the data file when a new core is appended in the real-time correlation workflow. The user will see the section summary file in the data folder but must not upload it separately (Correlator would try to load it like a regular data file). If the section summary does not exist or cannot be uploaded because of an incompatible format, an error dialog appears.

Method 3 (not needed on the JR)

Alternatively, section summary files can also be imported “manually” by right-clicking on the Section Summaries item in the Correlator Data Manager and selecting the Import Section Summary Files(s) option. Once the user browses to the appropriate file and selects it, an import dialog window opens showing (part of) the file content (Fig. 3.3-3). You can Import or Cancel.

Fig. 3.3-3. Manual section summary import.

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Note: the section summary can also be uploaded the same way as any data file, but that is usually meaningless because we don’t need to plot the sections that way. If you need to upload section summaries manually, make sure you do so from the Section Summaries item so Correlator uses them as intended.

3.4. Import core section images

Starting with Correlator version 4.0, you can use images for correlation. You need to prepare the images as described in section 3.1.

Important:

• You must first import some primary correlation data (and the associated section summary data) before you can import images.
  • If you don't, you get a warning (Fig. 3.4-1)
• The images must be JPEG format.
• The images should be ~230 pixels across since that is the maximum Correlator will display. That corresponds to maximum image sizes of ~200 kb.
  • If you try to import images >1 Mb you get a warning (Fig. 3.4-2).

To import images:

• Right-click on Images in the Data Manager window.
• Navigate to your local data directory
• Select the folder containing the JPEG images you want to import and click import.

3.4. Load data for correlation

Once correlation data have been imported to Correlator and are listed in the hierarchy of the Data Manager window, they reside in Correlator’s own local database. You still need to load the data for display and correlation.

To load data:

• Select, then right-click on a line item in the Data Manager window
  • You can load an individual file, a set of files for a data type, or all files for a site.
  • Typically, you just load the entire site because it is lightning fast.
  • Make sure that the files you want to load are enabled. If saved, affine and splice tables are enabled and will be applied to the loaded data. 
• Select Load.
  • The Data Manager view turns into the Display view, where the data is plotted and correlation and splicing functions are available.
• If you import data and switch to the Display view without loading, a message will appear in the plot window reminding you that you need to load the data for them to be plotted (Fig. 3.4-1).

Figure 3.4-1. Message when switching to the Display window after a data import without using the Load function.

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3.5. Update Correlator data

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