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The Core-Log Integration Platform (CLIP) software provides the ODP community with a set of graphic, interactive data analysis products for depth-merging and integrating core and downhole log data. These graphically oriented and intuitive products are for use on the ship or on shore-based Unix workstations. Splicer (current version: 2.2) and Sagan (current version: 1.2) have expanded data handling flexibility considerably, allowing for access to a variety of non standard data types and formats in addition to current Janus database output files.
Splicer is installed on Sun workstations on the JOIDES Resolution and allows interactive depth-shifting of multiple holes of core data to build composite sections using an optimized cross-correlation approach. Multiple data types can be compared simultaneously in order to quickly determine the best correlation for all variables. On legs where it is important to recover complete "spliced" sediment sections, a "Stratigraphic Correlator" will be staffed in order to provide real time feedback on the completeness of the recovered sediment record to help determine operational and drilling plans. Splicer has been used routinely on the JOIDES Resolution to build continuous sediment records since Leg 151 (1993). Metadata files generated by this program are now formally included in the JANUS database. Splicer also allows the composite section to be compared or tied to reference records such as insolation and isotope curves.
Some example applications are:
- Simultaneous comparison of multiple data types from multiple holes.
- Tying holes together to build a common "composite" depth scale.
- Build a continuous sediment section by "splicing" overlapping cores.
- Enter and compare stratigraphic data from various holes down the splice.
- Output data on the new composite depth scale (mcd) as well as mbsf.
- Output a continuous "spliced" records for further analysis.
- Tie the downhole spliced record to reference data such as insolation or isotope curves
The addition of the Sagan program now allows the composite sections output by Splicer to be mapped to their true stratigraphic depths, unifying core and log records and providing a crosscheck on the completeness of the composite section. Sagan generates a single metafile that defines a set of precise depth correlations between core and log datasets at any given site. This metafile provides the foundation for core-log data integration, as it establishes the unique mapping function linking the two independent depth scales. The program performs the core-log depth merging using physical parameters which are measured on both cores by logs (e.g. natural gamma, bulk density, porosity, magnetic susceptibility, sonic velocity). The core-log depth correlations are conducted either manually (e.g., core-by-core from single or multiple holes) or automatically. Sagan can also perform smoothing, decimation, and culling procedures to modify the data. The program can manage up to 10 holes of core data, 5 data types, nearly an infinite number of cores and data points and up to 3 reference log curves. The resulting core-log timelines can be applied across equivalent mcd depths in different holes or just for individual cores.
Some specific example applications are:
- Compare multiple core data types (in mbsf or mcd space) to downhole log records (log mbsf).
- Automatically or manually map core data back to log data to determine original stratigraphic depths.
- Accurately estimate the size and position of coring gaps, as well as the accuracy of the composite section.
- After mapping core data into the logs, the core data can be saved versus Estimated Log Depth (eld) as well as mcd and mbsf.
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