Mining the IODP Database for Relationships Between Lithology and
Physical, Chemical, and Magnetic Properties
Abstract
During each International Ocean Discovery Program (IODP) expedition a
vast array of data, typically amounting to hundreds of gigabytes to
several terabytes of information, are collected from drill cores. These
data include physical, chemical, and magnetic properties and digital
images collected continuously or every few centimeters along the cores
using automated track systems, as well as a variety of analyses
conducted on discrete subsamples taken from the cores. Coring just since
the start of Expedition 349 in January 2014 has recovered over 50 km of
core, resulting in a very large amount of data, most of which are
accessible from the IODP LIMS database. Some of the properties typically
measured include P-wave velocity, density, magnetic susceptibility,
natural remanent magnetization, natural gamma radiation, and visible
spectral reflectance. In addition, the lithology of all cores is
described based mainly on visual characteristics of the surface of the
split cores, visual examination of smear slides and thin sections, and
compositional or mineralogical information derived from geochemical
analyses. Our goal in this study is to mine these data for
interrelationships that would otherwise be difficult to assess given the
way the data are partitioned by specific property within the database.
In particular, we extract basic lithologic information from the complex
array of descriptive information and then tie that information to all
other observations in order to characterize the physical, chemical, and
magnetic properties of a myriad of lithologies.