ODP was an international partnership of scientists and governments who joined together to explore the structure and history of Earth beneath the ocean basins. The central purpose of ODP was to provide core samples, downhole measurements, and other scientific measurements to characterize the oceans' basins. The data generated are leading to a better understanding of the processes of plate tectonics, Earth's crustal structure and composition, conditions in ancient oceans, and changes in climate through time.
As the program Science Operator, Texas A&M University (ODP/TAMU) had the responsibility to collect cores from the ocean basins, provide adequate facilities for analyses of the cores, and assure the preservation of cores and scientific data collected by shipboard scientists. This program was very successful—ODP repositories hold >220 km of core and the databases contain millions of analytical measurements made on core sections and samples. By providing the drilling platform, consistent drilling procedures, onboard laboratories equipped with analytical equipment, and standard data collection procedures, ODP has created a suite of analyses from locations throughout the world's oceans that are directly comparable.
One of the primary tasks of the Science Operator was to collect, archive, and disseminate scientific data collected on the core during the cruises. Table T1 contains a list of the prime data types—analyses performed on the ship during a cruise with standard data collection procedures on all cores when practical.
Most of the scientific measurements are available using Web-based queries of the Janus database, an Oracle database created to serve data to the scientific community as well as maintain the prime data in a permanent archive. The Janus database is now maintained by IODP/TAMU, the U.S. Implementing Organization of IODP. The database maintains a set of queries that allows the user to extract data.
This Technical Note provides a general description of the prime scientific data types. For each data type, the following information is provided:
More detailed information about ODP data collection can be obtained from the technical notes that describe data collection for each of the different laboratories on the JOIDES Resolution. In addition, Explanatory Notes chapters at the beginning of each Initial Reports volume, Laboratory Officer's reports for each leg, laboratory technicians' reports, and log sheets provide additional information. This information can also be requested from the IODP/TAMU Data Librarian.
ODP started numbering the scientific cruises of the JOIDES Resolution at Leg 101 (Leg 100 was a trial run of the modified drilling ship). Leg duration was nominally 2 months. The Shipboard Science Party typically consisted of 25 scientists drawn from universities, governments, and industry around the world. During the 18+ yr of ODP, there were 110 cruises on the JOIDES Resolution.
A site is the location where one or more holes were drilled while the ship was positioned over a single acoustic beacon. The drillship visited 656 unique sites during the course of ODP. Some sites were visited multiple times, including some sites originally visited during DSDP, for a total of 673 site visits.
Several holes could be drilled at a single site by pulling the drill pipe above the seafloor, moving the ship some distance away, and drilling another hole. The first hole was designated "A," and additional holes proceeded alphabetically at a given site. Location information for the cruise was determined by hole latitude and longitude. During ODP, 1818 holes were drilled or deepened.
Cores are numbered serially from the top of the hole downward. Cored intervals are as long as 9.7 m, the maximum length of the core barrel. Recovered material was placed at the top of the cored interval, even when recovery was <100%. More than 220 km of core was recovered during ODP.
All cores are tagged by a letter code that identifies the coring method used. Some of the more common core types are
Cores are cut into 1.5-m sections in order to make them easier to handle. Sections are numbered serially, with Section 1 at the top of the core. Most of the scientific measurements were made on sections or discrete samples taken from the sections. Samples and measurement intervals are given in centimeters from the top of each section. After being cut into sections, several whole-core measurements were made, and then the core was split into working and archive halves. The archive halves were used for the visual descriptions, paleomagnetism, and photography. The working halves were sampled for shipboard and shore-based studies.
As soon as core was brought on deck, a paleontology sample was usually taken from the core catcher in order to obtain an initial age assessment. It was then put into a long rack where Vacutainer gas samples could be taken from voids. Sections were marked, labeled, and cut. Whole-round samples were taken. Each section was sealed with color-coded caps glued on the top and bottom: a blue cap for top of section, a clear cap for the bottom, and a red cap for where a whole-round sample was taken.
The sections were moved to the core laboratory where they were labeled with an engraver to mark the full identification of the section. The length of core was measured for each section and core catcher and the lengths were entered into the database. The cores were equilibrated to room temperature, run through the MST, which included GRA densiometer, MSL, NGR sensor, and PWL, and thermal conductivity measurements were made.
The sections were then split into working and archive halves. The softer sections could be split with a wire, more indurated sections were cut with a saw, and harder rock cores were split with a band saw or diamond saw. The archive halves were wrapped and taken to the core description area where scientists completed VCDs. The archive halves were analyzed using the pass-through cryogenic magnetometer. The working halves were available for sampling. Routine samples for shipboard laboratory analyses were taken. In addition, scientists who requested personal samples could take samples for their own research. These could be analyzed in the shipboard laboratories or taken back to the scientists' laboratories. All samples were entered into the database and included location information (leg, site, hole, core, core type, section, and top and bottom intervals) and volume of sample.
Most of the analytical laboratories on the ship were equipped with analytical equipment that interfaced to computers. Early in the program, these programs were fairly basic, but as technology advanced, the data acquisition programs became more advanced. Sections and samples were identified by barcode after Leg 171, but the implementation of barcode readers on each of the analytical systems had not yet been accomplished.
Most data collection in the shipboard laboratories involved at least one manual data entry event (e.g., sample entry into database, section or sample information entry to data acquisition program, data entry into databases, or reformatting of data tables for the Initial Reports volume). Core and section information were checked very closely, but verification of every sample, analysis, and run was an enormous task during the operational time of a cruise. Operator entry or typographical errors probably account for the largest number of errors.
Several of the prime data types have been captured digitally since the beginning of the program. Files were created on computers in the laboratories and transferred to the central computer for compilation and transfer back to shore at the end of the leg. ODP/TAMU retained many of the original raw files on an active server, with each new leg added after data returned from the ship. These files were maintained as an archive and are made available to the scientific community on request to the IODP/TAMU Data Librarian.
During the early part of ODP, the Science Operator recognized the need for a data management system to help storage and retrieval of the scientific data and consequently chose System 1032 by Computer Corporation of America, or S1032. Most of the scientific data collected on samples (e.g., MAD properties, carbonate analyses, etc.) were loaded into S1032 and the original files were not saved online. The media used to transfer data between ship and shore are obsolete, so retrieval of the original raw files for some data sets is no longer possible.
Database technologies evolved throughout the program, and ODP scientists and staff were continually looking for more efficient and effective ways to capture the information collected on the ship. S1032 was used for a variable length of time depending on the data set. Some effort was made to move some data sets (e.g., MAD properties and paleontology) into 4D, a relational database running on the Macintosh computer system. For some data types, it was decided to archive the original files. There were problems with these database engines, including software upgrades that could not read databases created with earlier versions, and some versions of these databases were easily corrupted.
The continuing improvement in database technology and the explosion of scientific databases accessible over the Internet convinced ODP/TAMU to create a database that would provide a permanent archive for the scientific data and could be accessed by the public through an Internet interface. Janus, an Oracle-based relational database, was created and has become the repository for all core and sample information and most of the shipboard scientific data. Janus became operational during Leg 171, January 1997. From that point, the scientific data generated on board ship were uploaded to Janus, but the original data files were still brought back to shore and archived. Janus Web was created to provide standard data queries that allowed the public to look at or download data from Janus.
Before Janus became operational, verification of the scientific data collected during a cruise was the responsibility of the leg Scientific Party. Minimal checking or verification was done after the data were brought back to shore. However, when Janus became operational during Leg 171, more complete verification of leg-associated scientific data became necessary. The relational characteristics of the Janus database require more active oversight by database managers to ensure that integrity of the data is maintained. ODP data verification procedures include
• Data acquisition: Confirming that the data acquisition software is recording all the data necessary to document each analysis and ensuring that Janus has a place to put every piece of information that should be saved,Data checking was by far the most difficult and sensitive task for database personnel. Procedures were instituted to verify that the data from a leg was properly entered into the Janus database and, at the same time, reassure the scientific community that database personnel were not changing data without the knowledge and permission of the Scientific Party. These procedures are as follows:
Unfortunately, the verification of the pre-Janus migrated data was a more difficult problem. Log sheets and laboratory notebooks were not available for most of the legs' data sets. The important link of interacting with the scientists and technicians who collected the data was mostly missing. The main resource was the Initial Reports volumes. When there was a discrepancy, all available information was studied in order to determine the nature of the discrepancy. Data in the database were only changed when there was compelling evidence that data in the Initial Reports table were wrong. Some of the data-specific verification techniques and common sources of errors are discussed in the following data sections.
A comprehensive list of all the reports, log sheets, notebooks, conversations, hand-written notes, and so on, used to compile the information for the data summary reports is impossible. For additional information about any aspect of the ODP data collection procedures, please contact the IODP/TAMU Data Librarian: