Appendix : Terms and Definitions


A.1. Archive and Working Halves

Cores are split into halves for shipboard analysis to uniquely identify split-core halves for measurements and sampling. The halves are referred to as the “working half (WH)” and “archive half (AH).” The entire working half is available for sampling. The concept and definition of an archive half is designed to enhance scientific flexibility and to enable greater access to important material. In certain circumstances the archive half is also available for sampling (see section A.5).

A.2. Composite Splice

Drill-ships typically recover cores from multiple holes cored side by side at a given site using various coring systems. A composite stratigraphic depth section is constructed by establishing correlations between adjacent drill holes, using the variations in properties measured on cores by nondestructive methods. A composite depth table describes the resulting (delta) depth offsets between holes. These offsets represent the difference between the meters below seafloor (mbsf; i.e., cored depth) and the meters composite depth (mcd) values that are derived from these correlations. Another data table describes the unique intervals in specific holes at a given site that have been used to construct the “ideal” section, also known as the “composite splice.” The purpose of a composite splice is to describe the most complete sedimentary section at a given site, without gaps in core recovery (i.e., missing sediment), which then can be used for developing high-resolution sampling strategies and analyzing time series. Scientists often prefer to sample using the composite splice as a guide, rather than to sample down a single hole at a given site, because of gaps in recovery between cores in a single hole.

A.3. Critical Intervals

Critical intervals are lithologic spans of such scientific interest that there is extremely high sampling demand for them. These intervals may vary from thin, discrete horizons to thick units extending over an entire core or more. Examples include, but are not limited to, décollements, sediment-basement contacts, igneous contacts, impact/tektite horizons, gas hydrates, marker ash horizons, scaly fabric, magnetic reversals, and particular biostratigraphic levels. The Sample Allocation Committee (SAC) is responsible for anticipating the recovery of critical intervals and for developing a strategy for sampling and/or conserving them. For post-moratorium sampling, the Curator will work with investigators to ensure that previously defined critical intervals are sampled only when necessary.

A.4. Permanent Archive

A “minimum permanent archive” is established for each IODP drill site. Archive core earmarked “permanent” is material that is initially preserved unsampled and is conserved in the core repositories for subsequent nondestructive examination and analysis. In “unique intervals,” this minimum permanent archive consists of at least one half of each core, excluding whole-round samples that require more than the working half (e.g., for interstitial pore water analysis). If so desired, the SAC may choose to designate more, but not less, than this amount as the permanent archive. In “non-unique intervals,” the permanent archive will consist of at least one half of one set of cores that span the entire drilled sequence, again, excluding whole-round samples. The permanent archive is intended for science needs that may arise five years or more after drilling is completed.

In practice, if holes are cored continuously, the minimum permanent archive may consist of one half of each core taken from the deepest hole drilled at a site. As such, the archive halves of cores from additional holes drilled to equal or shallower depths that contain replicate copies of stratigraphic intervals constituting the minimum permanent archive need not be designated as permanent archive, but can be, if so desired by the SAC. If not deemed permanent archive, these cores are “temporary archive.” If a composite splice section is constructed and the sampling demand exceeds the working half, an alternative curatorial strategy may be required to ensure that all samples can be taken from the spliced section. In this case, the permanent archive can be defined from cores that are not part of the splice (e.g., from cores from different holes). Sampling of the permanent archive is feasible five years post cruise if the working and temporary archive halves of the core have been depleted.

A.5. Temporary Archive

Cores taken from non-unique intervals that are not part of the “minimum permanent archive” will be considered “temporary archives” unless stipulated otherwise by the SAC in the Sample Strategy. If required for special shore-based analysis, some cores may be left unsplit on the platform and shipped to the designated IODP core repository or laboratory as whole-core sections. If split (the common scenario), the temporary archive may be sampled just as the working halves are when (a) either the working halves have been depleted by sampling or (b) when pristine, undisturbed material is needed for special sampling needs, such as taking U-channels or slab samples.

A.6. Unique and Non-unique Intervals

A cored interval is designated “unique” if it has been recovered only once at a drill site. The most common occurrence of a unique interval is one that results when only one hole is drilled at a site. If the cored interval is recovered from two or more holes, then the interval is considered “non-unique.” A critical exception to this definition occurs when drilling into igneous basement rocks, metamorphic rocks, or metalliferous deposits. Every hole drilled into these lithologies is considered unique because of their inherent lateral heterogeneity. Lithostratigraphic analysis of advanced piston cores from multiple holes drilled at one site may reveal that short sedimentary intervals (generally less than 2 m) are commonly missing between successive cores from any one drill hole, even where nominal recovery approaches 100%. These missing intervals can be ignored when considering whether or not an interval is unique.

A.7. Whole Round

Whole rounds are collected for special analysis (e.g. interstitial water analysis) and pre-defined purposes (e.g. "community" whole round and DeepBIOS). Intervals of whole rounds depend on the pre-defined purposes of sampling and type of special analyses applied. The SAC is responsible for developing a strategy for whole round sampling in the early stage of expedition planning and for including a clear description of the whole round sampling strategy in the IODP Scientific Prospectus.

A.7.1. “Community” Whole Round

“Community” whole rounds are collected in order to preserve an “archive” of unsplit material for future tests for a variety of purposes. Science party members with common research interests decide some intervals of cores to be treated as "Community" whole rounds under agreement with SAC. “Community” Whole Rounds are treated as “special” archives and are made available to science party members after approval of their sample requests by the SAC. In the Post-moratorium period, these whole rounds are available to any requester after approval of his/her sample request by the Curatorial Advisory Board (CAB). If necessary, the CAB can seek advice from other experts on specific sample requests.

A.7.2. “DeepBIOS” Whole Round

Deep BIOsphere Samples (DeepBIOS) are the 10 cm long core material stored at very low temperatures (-80℃ and/or -160℃) right from the time of their collection onboard a scientific drill ship. This is considered to be a method of preventing the degradation of fragile bio-molecules such as DNA, RNA, enzymes, sugar chains, and intact polar lipids. Quality of the DeepBIOS is evaluated based on fluorescent bead contamination test and/or cell-count experiment. Aliquots of these samples are shipped on dry ice or in dry shipper, and sample requesters may be asked to bear the shipping costs. DeepBIOS collected from the Exclusive Economic Zone of some countries may require compliance with the laws of that country governing such samples.

A.8. IODP Community Thin Sections

Thin sections made during DSDP, ODP, and now IODP drilling cruises (on the D/V JOIDES Resolution, on the D/V Chikyu, or during an Onshore Science Party of MSP Expeditions) arethe property of IODP, for long term use by the science community, because they are thereference thin sections for lithologic/petrologic data gathered by expedition scientists, storedin IODP science databases, and published in the Expedition Reports (IODP Proceedings, Initial Reports). They are termed hereafter as 'community thin sections (CTSs)', to establishtheir crucial difference from personal thin sections made by scientists using personallyrequested samples. The responsibility of safekeeping, safe transport, inventory control, long-term preservation, and lending of the CTSs rests with the IODP Curator and Repository Staff.Since DSDP, CTSs made during cruises have incurred many losses, resulting in very largegaps in the overall collection1. To minimize future loss of this highly valuable referencematerial and so that the wider scientific community may have greater access to it, we have the following procedures:

A.8.1. Primary Conditions for Use of CTSs

CTSs, being the property of IODP, may only be loaned to requesters, with a signed loan agreement containing a pre-determined loan duration of no longer than 1 year, after which they must be returned to the IODP core repository. If a requester possesses CTSs from previous requests beyond their approved loan duration, he/she cannot receive additional CTSs or other IODP samples until they return the overdue CTSs to the appropriate IODP core repository. Exceptions may be considered for cases with valid scientific justification from the requester. Once CTSs have been returned to their repository, they may be requested for use by anyone, including the previous requester, for a new approved loan duration.

A.8.2. Moratorium Follow-up Requests for CTSs

Requests during an expedition for further Moratorium-period onshore analyses of the expedition's CTSs must contain a specified list of the CTSs to be sent to each scientist, with a predetermined loan duration for each scientist to complete their analyses. This list and loan duration, constituting a loan agreement, must be submitted to the SAC for approval. If the CTSs are made onboard ship, the CTSs along with the distribution list/loan agreement will be shipped to the IODP core repository first, and then shipped from there to the requesters. Under no circumstances may expedition scientists be given CTSs to hand-carry to their laboratory, to avoid the risk of loss or damage during travel, including delays or problems with customs and import controls, lost or mishandled baggage by air carriers, or having them stolen along with other luggage, etc.

Shipments made by the onboard staff will ensure the CTSs arrive safely at the IODP core repository. If a core shipment will only take 1-2 weeks to arrive at the repository, then the CTS collections will be sent with the core shipment. If the core shipment will take several weeks or more to arrive at the repository, then the thin sections will be sent separately by air freight, using the experienced staff onboard ship to ensure they arrive quickly and safely at the repository.

A first post-expedition action item for the repository will be to distribute the CTSs using typical 1-2 day air freight to the designated scientists, along with copies of the distribution list/loan agreement, containing the approved loan duration for each scientist. The repository staff will also contact each scientist before shipping to ensure they or their representative will be at their work address to receive the CTSs. Under no circumstance may scientists forward CTSs directly to another scientist. Instead, they must return CTSs to the repository at the end of their approved loan duration, for inventory and for checking on the state of the CTSs (e.g., broken, complete, etc.). The repository will be responsible for quickly forwarding CTSs to other scientists. As with regular sample requests for core samples, formal requests for borrowing expedition CTSs may be either added to a pre-existing sample request, or, if more appropriate, a new request should be submitted if it involves several people wanting to continue moratorium analyses on the same set of CTSs in a coordinated sharing schedule.

A.8.3. Post-Moratorium Requests for CTSs

Requests for CTSs submitted after the moratorium will be reviewed for approval by the appropriate IODP Curator or repository staff. Depending on the number of CTSs requested (> 15 nos.) by one person at any time, the number of approved CTSs first sent to the requester may only be a portion (e.g., from 25-50%) of the total approved. Return of the first portion of approved CTSs to the repository will result in the shipment of the subsequent portion or portions of the CTSs to the requester. This procedure for requests of large numbers of CTSs will help ensure that they will get returned to the repository at the end of the research project. Requests for small numbers of CTSs (e.g., <10-15) may be filled with one shipment of all CTSs. The disposition of CTSs for each request will be up to the responsible Curator and repository staff to decide on a case-by-case basis.

1The reasons for this are manifold: the primary misconception of many scientists who receive these is that they are considered to be their own personal samples, similar to their other personal core samples. From this standpoint, many scientists have forgotten agreements and promises to return them after a year or longer. Some may have shared the thin sections with graduate students and other colleagues, and the collections got dispersed without traceable records. Repeated attempts by curatorial staff, in DSDP, ODP, and now IODP to track down and collect outstanding community thin sections have resulted in very little success. Scientists either do not know where the thin sections are, claim to be unable to send them back, or even do not reply. A very few scientists have decided to not return community thin sections that they acknowledge they have, because they say they may have future need of them for research or teaching.

A.9. Sampling Strategy

To ensure the best possible use of the core and distribution of samples, a sampling strategy is developed by the SAC for each drilling project during pre-expedition planning. The strategy will integrate and coordinate the programs for drilling, sampling, and downhole measurement to best meet the drilling project’s objectives and the scientific needs of the Science Party. The strategy may evolve during the expedition and the moratorium period.

Once a proposal has been scheduled for drilling and the Co-Chief Scientists have been selected, the SAC will write a formal expedition-specific sampling strategy that meets the specific objectives of the expedition and define the minimum permanent archive and any supplements that the SAC deems necessary. The strategy will be published in the IODP Scientific Prospectus series. The Sampling Strategy becomes the basis of the sampling plan used during the drilling project and the moratorium period.

A successful sampling strategy will
• Define the amount of core material available to the Science Party for sampling by deciding if and when more than a minimum permanent archive is needed;
• Anticipate and possibly define limits on the volume and frequency of shipboard sampling for routine analyses, pilot studies, and low-resolution studies;
• Estimate the sampling volume and frequency that is needed to meet the objectives of the expedition, as per scientific sub-discipline and request type;
• Anticipate the recovery of critical intervals and develop a protocol for sampling and/or preserving them;
• Propose where and when sampling will occur;
• Determine special sampling methods and needs (e.g., Pressure Core Sampler, microbiology, whole rounds);
• Consider any special core storage or shipping needs (e.g., plastic wrap, freezing sections); and
• Identify disciplines/personnel needed for shore-based sampling.

The Sampling Strategy should be formatted using the following categories.
• Needs
• Critical intervals
• Sampling timetable
• Permanent archive
• Temporary archive
• General sampling procedures

Scientists may obtain samples by submitting a sample request in a database.

A.10. Moratorium Period Sampling

During the moratorium period, which is usually 1 year long and begins soon after completion of major sampling of the cores either onboard ship or in IODP core repository, only members of the drilling project Science Party receive samples.

A.11. Post-moratorium Period Sampling

After the moratorium period has expired, samples may be provided to any researcher, educator, museum, or outreach institution with the resources to complete a scientific investigation or prepare materials for educational or curatorial purposes.

A.12. Sample Request Approval

A.12.1. Moratorium Period

The SAC will supervise moratorium period sampling. After reviewing the sample requests, approval will be based on compatibility with the Sampling Strategy. Sample requests will be approved if a majority of the SAC endorses the requests. In cases where a sample request is considered incompatible, the SAC may (1) recommend modifications to the request, (2) modify the Sampling Strategy, or (3) reject the request if the other options are inappropriate. In the event of an evenly divided vote, the Platform Curator will make a decision. The sample requester may choose to appeal any decision to the CAB. If a conflict arises over the allocation of samples during the moratorium period, expedition participants have priority over other scientists in the Science Party.

A.12.2. Post-moratorium Period

The Repository Curator and the CAB supervise post-moratorium sampling. The Repository Curator will evaluate post-moratorium sample requests for completeness and adherence to the provisions in this policy. When considering a sample request, the Repository Curator will ascertain whether the requested material is available in the working half or the temporary archive half of the core. If the material is unavailable, the Repository Curator will consult with the requester to determine if the range of the requested interval(s) or the sample spacing within the interval(s) can be modified. If the request cannot be modified because of scientific requirements, a request to sample the permanent archive will be considered.

Approval of sample requests will be based on the availability of material and the length of time it will take the investigator to complete the proposed project. Typical studies will take two to three years, but a study of longer duration will be considered under certain circumstances. If a sample requester disagrees with the Repository Curator’s final decision, the sample requester may choose to appeal any decision to the CAB. All requests to sample permanent archive material will be reviewed by the CAB after preliminary review by the Curator. The CAB will evaluate the request based on its scientific merit and on the extent to which the working half is depleted. If necessary, the CAB may also consult with members of the original SAC who established the permanent archive being considered for sampling. The CAB will strive to maintain a representative continuous section of core material for archival purposes whenever possible.

A.13. Typical Sample Volumes

The following volumes are guidelines, not limits:

A.14. Sample Distribution

Sample requests are processed differently depending upon whether they are shipboard, moratorium, or post-moratorium. Post-moratorium Sample Requests are processed in order of approval. This approximates the order of submission and receipt of requests, however the review and approval process may cause certain requests to be delayed for various reasons, e.g., lack of available material causing a discussion and revision of which cores to be sampled. In addition, after approval, other factors may cause requests to be processed out of order, e.g., a request for thousands of samples may take several weeks of labor to complete, whereas requests for small numbers of samples may take only hours. When different sized requests are pending at the same time at a repository, small requests may be completed before or during the work on a large request, so that they are not all held up by the large request. Requests that are tied to visits to the repository by the requester are dependent upon the schedule of that visit. Requests for material from more than one repository are processed separately at each repository following the procedures and exceptions above. Most requests of small to moderate size and complexity may be expected to be processed within a month.




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