The Correlator-Corelyzer Link
During this cruise, a fantastic tool called “Correlator-Corelyzer Link” enables us to look at fine linescan images of recovered cores with wiggle-matching of core-logging data sets. It is the first time to use as a test-drive mode. Until the middle of the cruise, we could not use this tool because a downloaded data from the shipboard database (LIMS) using a program called LIMS2CorrelatorDownloader had the wrong format to be used in the “Correlator-Corelyzer Link”. The shipboard Application developer, Stephanie Zeliadt, fixed the format of the data and now the link is working for correlators!
The stratigraphic correlators always use the core logging data sets of the whole-round multi-sensors, the logging team, etc. that are digital non-destructive (no core material is damaged) core measurement data sets. But with all of these data sets to correlate, it becomes very difficult to identify what kind of sediment each represents or what the various peaks and troughs in the data mean. Because the correlation has to be done not only at the levels of 10 meter long cores but also at scales of 200, 300 and 400 meters long. This means that hundreds of sections have to be checked comparing individual images. In this, the fantastic links we can make between “Correlator” (the graphical data) and “Corelyzer” (the core imaging) become a great tool to accomplish shipboard correlator’s task.
We can make a tie (or connection) point between different holes at the site (See the example picture that is a captured image of “Corrleator-Corelyzer link”). The small iPhone-like window in the lower left shows the active phase of the “Corrleator-Corelyzer link” (Cool! I like it). The red point is a reference point and the green dots are target points. If we make the connection, a red line appears on the Corelyzer. Then if I shift the tie point up and down in the Correlator, the image of the target on the core is moved with the cursor!
Actually, I was on board as sedimentologist during the ODP phase (legs 160 and 186) and I’ve done the same kind of work by hand-editing. Since the corelyzer has great flexibility, and we can zoom-up and zoom-down into the images, we can do correlation with a very fine-scale (on the centimeter scale). The picture above shows I am going to be correlating the bottom base of laminated diatom ooze intervals. This is a fantastic tool for us although we need much more development in the details such as depth matching between the two software packages.
[Top photo credit; Tats Sakamoto and 323 shipboard scientists]