MSP offshore data storage and computer facilites
Data management performs the following functions:
- systematic capture and storage of data during expeditions, using documented procedures, formats and standards
- the generation of metadata (a description of the data and its content)
- quality control of the data
- access to the data, initially by the expedition scientists only, and later by the scientific community, via the metadata
- archival of the data for the foreseeable future
For Mission Specific Platform (MSP) expeditions, the data management process can be divided into three phases.
The Offshore Phase lasts for the duration of the offshore drilling operation. Due to the limited facilities onboard mission specific platforms, only basic scientific data are generated. Data types include core and sample metadata, core-catcher photographs, initial lithological descriptions and measurements, multi-sensor core logs, ephemeral properties, microbiological observations, downhole logs, drilling parameters and expedition documentation.
The Onshore Phase begins when the drilling operation is completed and lasts until the end of the moratorium period. On completion of the Offshore Phase all data are transferred to the Bremen Core Repository and are available to expedition scientists via a password-protected data portal. It is during this phase that the bulk of the scientific data and interpretations are generated, especially during the onshore science party in Bremen. Examples of additional data types generated during this phase are visual core descriptions of the split cores, high resolution line-scan and core overview images, XRF and XRD measurements and stratigraphic data.
The Post-expedition Phase begins at the end of the moratorium period. In this phase the data management process changes from the capture of expedition data to archiving of the data, and provision of the data to the scientific community. This is when the expedition data are transferred to WDC-MARE PANGAEA, the world data centre for marine data. The downhole log data are transferred to the LDEO IODP Log Database. Metadata are also exported to the IODP Sample Management and Curation System (SMCS) and the IODP Scientific Earth Drilling Information System (SEDIS).
The data management system implemented by ESO for MSP expeditions is described in an article in Scientific Drilling (Scientific Drilling No.4, March 2007, p. 32-34).
The primary data capture system used on MSP expeditions is the ExpeditionDIS. A user manual for the ExpeditionDIS is available here.
Data Management System
The most convenient way to manage digital information is by implementing a relational database management system. The database contains both data and metadata. Not all data types need to be stored in the database. For example, it is more convenient to store images in a file structure. In this case, metadata describing the images is stored in the database along with a link to where the image files are located in the file system. The database also stores metadata for the physical cores and samples.
The input, query, retrieval and reporting functions are provided by one or more applications (computer programs).
ESO uses the Drilling Information System (DIS), a relational database management system developed for the International Continental Drilling Program (ICDP). This is designed as a portable and flexible data management system capable of being deployed in a variety of drilling scenarios. Among the many different types of drilling projects run by ICDP, it is used for ICDP lake-drilling projects, which are similar in many ways to IODP MSP expeditions.
A special version of the DIS has been developed jointly by ESO and ICDP – the ExpeditionDIS. This is an integrated data management system based on the SQLServer relational database. The architecture is client/server. Typically, SQLServer and the central file system are located on a server PC, while users access the database and file system from one or more client PCs (although the entire system can be run on a single PC if necessary). Almost all of the data management and user functions are packaged in a single application, which can be installed on any PC which has Microsoft Access installed.
It is also possible to access the ExpeditionDIS database and many of the DIS functions via a web interface called the XDIS. This allows users to access the database remotely via the internet. It also allows client PCs running operating systems other than Microsoft (for example, Apple PCs) to access the database and applications.
In addition to the ExpeditionDIS, expeditions also require a shared file area for storing data types that are not loaded to the relational database, and for general purposes (for example writing reports and sharing documents). This area is also used as a preparation area for data that are subsequently uploaded to the ExpeditionDIS (for example, MSCL measurements). The structure and naming conventions of this file system make it easy to drill down to a specific set of measurements for a site, hole, core and section. This, and standard filename conventions makes it possible to automate, or at least semi-automate uploading of data to the ExpeditionDIS.
Each expedition has its own individual ExpeditionDIS system configured specifically for that expedition (for example, ACEX DIS and Tahiti DIS). The ExpeditionDIS is used during both Offshore and Onshore phases, and the configuration may differ for each phase. During the onshore science party the same general IT setup is available.
At the beginning and during the offshore and onshore phases scientists will be advised and assisted in using the data system by data managers.
The data management system implemented by ESO for mission specific platform expeditions is described in an article in Scientific Drilling.