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Ciesielski, P. R, Kristoffersen, Y., et al., 1988Proceedings of the Ocean Drilling Program, Initial Reports, Vol. 1141. EXPLANATORY NOTES1Shipboard Scientific Party2Standard procedures for both drilling operations and prelim-inary shipboard analysis of the material recovered during DeepSea Drilling Project (DSDP) and Ocean Drilling Program (ODP)drilling have been regularly amended and upgraded since drill-ing began in 1968. In this chapter, we have assembled informa-tion that will help the reader understand the basis for our pre-liminary conclusions and also help the interested investigator se-lect samples for further analysis. This information concernsonly shipboard operations and analyses described in the site re-ports in the Initial Reports, of the Leg 114 Proceedings of theOcean Drilling Program. Methods used by various investigatorsfor further shore-based analysis of Leg 114 data will be detailedin the individual scientific contributions published in the FinalReports, of this volume.AUTHORSHIP OF SITE REPORTSAuthorship of the site reports is shared among the entireshipboard scientific party, although the two co-chief scientistsand the staff scientist edited and rewrote part of the materialprepared by other individuals. The site chapters are organizedas follows (authors are listed in alphabetical order in parenthe-ses; no seniority is implied):Site Data and Principal Results (Ciesielski, Kristoffersen)Background and Objectives (Ciesielski, Kristoffersen)Operations (Clement, Storms)Sedimentology (Bourrouilh, Hodell, Muller, Warnke, Wes-tall)Basement Rocks (Bourrouilh, Hodell, Hughes, Muller, Per-fit, Warnke, Westall)Biostratigraphy (Crux, Fenner, Katz, Ling, Nocchi, Ciesiel-ski)Paleomagnetics (Clement, Hailwood)Inorganic Geochemistry (Froelich)Physical Properties (Mienert, Nobes)Downhole Logging (Blangy, Mwenifumbo)Seismic Stratigraphy (Kristoffersen, Ciesielski)Summary and Conclusions (Ciesielski, Kristoffersen)Following the text of each site chapter are summary graphiclithologic and biostratigraphic logs, core descriptions ("barrelsheets"), and photographs of each core.SURVEY AND DRILLING DATAThe survey data used for specific site selections are discussedin each site chapter. Short surveys using a precision echo-sounderand seismic profiles were made aboard JOIDES Resolution onapproaching each site. Geophysical data collected during Leg114 are presented in the "Underway Geophysics" chapter (thisvolume).1 Ciesielski, P. R, Kristoffersen, Y., et al., 1988. Proc. ODP, Init. Repts., 114:College Station, TX (Ocean Drilling Program).2 Shipboard Scientific Party is as given in the list of Participants preceding thecontents.DRILLING CHARACTERISTICSBecause water circulation down the drill hole is open, cut-tings are lost onto the seafloor and cannot be examined. Theonly available information about stratification in uncored orunrecovered intervals, other than from seismic data or wireline-logging results, is from an examination of the behavior of thedrill string as observed and recorded on the drilling platform.Typically, the harder the layer, the slower and more difficult it isto penetrate. A number of other factors, however, determine therate of penetration, so it is not always possible to relate drillingtime directly to the hardness of the layers. Bit weight and revolu-tions per minute, recorded on the drilling recorder, also influ-ence the penetration rate.DRILLING DEFORMATIONWhen cores are split, many show signs of significant sedi-ment disturbance, including the downward-concave appearanceof originally horizontal bands, haphazard mixing of lumps ofdifferent lithologies (mainly at the tops of cores), and the near-fluid state of some sediments recovered from tens to hundredsof meters below the seafloor. Core deformation probably occursduring one of three different steps at which the core can sufferstresses sufficient to alter its physical characteristics: cutting, re-trieval (with accompanying changes in pressure and tempera-ture), and core handling on deck.SHIPBOARD SCIENTIFIC PROCEDURESNumbering of Sites, Holes, Cores, and SamplesODP drill sites are numbered consecutively from the first sitedrilled by Glomar Challenger in 1968. Site numbers are slightlydifferent from hole numbers. A site number refers to one ormore holes drilled while the ship is positioned over a singleacoustic beacon. Several holes may be drilled at a single site bypulling the drill pipe above the seafloor (out of one hole), mov-ing the ship some distance from the previous hole, usually a fewtens of meters, and then drilling another hole.For all ODP drill sites, a letter suffix distinguishes each holedrilled at the same site. For example, the first hole takes the sitenumber with suffix A, the second hole takes the site numberwith suffix B, and so forth. This procedure is different fromthat used by DSDP (Sites 1 through 624) but prevents ambiguitybetween site- and hole-number designations.The cored interval is measured in meters below the seafloor.The depth interval of an individual core is the depth below theseafloor that the coring operation began to the depth that thecoring operation ended. Coring intervals are determined by themaximum length of a core barrel, 9.7 m. The cored intervals,however, may be shorter and may not necessarily be adjacent toeach other but may be separated by drilled intervals. In soft sed-iment, the drill string can be "washed ahead" with the core bar-rel in place but not recovering sediment by pumping water downthe pipe at high pressure to wash the sediment out of the way ofthe bit and up the space between the drill pipe and wall of thehole. The presence of thin, hard rock layers can result in "spotty"sampling of these resistant layers within the washed interval.SHIPBOARD SCIENTIFIC PARTYCores taken from a hole are numbered sequentially from thetop of the hole downward. Maximum full recovery for a singlecore is 9.7 m of sediment or rock in a plastic liner (6.6-cm inter-nal diameter), plus about a 0.2-m-long sample (without a plasticliner) in a core catcher. The core catcher is a device at the bot-tom of the core barrel that prevents the core from sliding outwhen the barrel is being retrieved from the hole. The sedimentcore, which is in the plastic liner, is then cut into 1.5-m-long sec-tions that are numbered serially from the top of the sedimentcore (Fig. 1); the routine for handling hard rocks is described inthe "Basement Rocks" section (this chapter). When full recov-ery is


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