ODP Technical Note 10


B. Advance Planning Requirements for Routine ODP Tools

It is important to understand that just because a measurement is called "routine" does not mean that it can be made under all circumstances or without significant preparation by ODP technical support staff. Successful use of all downhole tools generally requires some warning prior to sailing, to make sure that proper supplies are available, and to undertake training of scientific and technical personnel. To ensure successful use of specific ODP downhole tools on a particular leg, it is advisable to start planning at least 1 year pre-cruise, and it is essential to keep two organizations fully informed: ODP itself, and the JOIDES panel structure via the Downhole Measurements Panel (DMP).

ODP is charged with implementing the scientific planning approved by the JOIDES Planning Committee (PCOM), which acts with the advice of the JOIDES panels, including DMP. About one year pre-cruise, DMP considers the proposed programs for logging and downhole measurements for each site of each leg, and passes its advice to PCOM, to ODP, and to LDEO. In its deliberations, DMP reviews measurements included within normal drilling proposals and separate proposals for special experiments. During the first 9 operating years of ODP, DMP has generally endorsed full programs of logging and downhole measurements at most sites, and PCOM has often accepted this advice unless ship time is very limited.

Thus, "normal" programs for use of ODP tools are usually approved for all sites by DMP and PCOM. However, details of implementing these programs are often not considered by these committees, but instead are left to the co-chief scientists to specify at the cruise planning meeting that normally occurs about 4-8 months pre-cruise at ODP. Co-chiefs for individual legs generally value the advice of DMP and consider it carefully when planning cruise operations. To ensure that ODP is fully equipped and staffed to support a program of routine downhole measurements on a given leg, it is essential that the co-chief scientists develop a comprehensive plan for these measurements well before this pre-cruise meeting.

For extraordinary programs of downhole measurements with ODP tools - e.g., special holes devoted to pore-water sampling and temperature measurements, long-term observatories, or extensive programs of packer measurements - JOIDES approval is required well before the pre cruise meeting to guarantee the necessary ship time and extra effort by ODP. Such approval can be obtained by including the plans for special downhole measurements in the original drilling proposals considered by the JOIDES panels, or by submitting special proposals to JOIDES for consideration by DMP and PCOM. The most important point to glean from this manual is that use of these tools almost always requires some advance warning and preparation.

ODP technical staff (marine specialists) are now asked to perform more and more complicated tasks than they were when the program started. Due to berthing restrictions, there are never enough marine specialists to cover all shipboard labs 24 hours per day. ODP will generally staff each leg with at least one marine specialist trained in the use of one or more downhole tools, although this person will probably have catwalk, core lab, and other duties. The downhole tools marine specialist is generally responsible for preparing and deploying tools, initial transfer of raw data to the shipboard computer, and standard processing for archival at ODP. The shipboard scientists are then responsible for further processing and data interpretation. Some of the computer programs available shipboard for this processing are discussed in later chapters. The boundary between science and technical support for downhole tools is necessarily vague and depends strongly on the experience of the persons involved, the shipboard workload, and the scientific needs of each cruise.

Extra attention should be paid to laying groundwork for the use of nonstandard, third-party downhole tools during ODP cruises. The official guidelines for development, testing, and deployment of third-party tools during ODP cruises have been published in the JOIDES Journal (February 1991) and are now being prepared for general distribution as a pamphlet; these guidelines are listed and discussed in Chapter VIII of this Technical Note. Note that these are conceptual and planning guidelines; they do not include technical specifications (tool size and weight restrictions, data formats, etc.). It is the responsibility of the tool developer to contact and work with representatives of ODP and LDEO to make sure that third-party tools are compatible with shipboard operations.

To Introduction, Section C.
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