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Table T1. Definition of lithostratigraphic and lithologic units, descriptive intervals, and domains, Expedition 350.

JOIDES Resolution Typical thickness
range (m)
JOIDES Resolution data logging
spreadsheet context
Traditional sediment drilling Traditional igneous
rock drilling
Comparable nondrilling
Lithostratigraphic unit 101~103 One row per unit in “lithostrat” summary tab; numbered I, II, IIa, IIb, III, etc. Used as specified; however, often referred to as lithologic unit in the past. Typically not used when only igneous rocks are drilled. Not specified during field campaign. Formal names need to be approved by stratigraphic commission.
Lithologic unit 101~101 One row per unit in “lith_unit” summary tab; numbered 1, 2, 3, 4, etc. Typically not used because descriptive intervals correspond to beds, which are directly summarized in lithostratigraphic units. Similar concept: facies type; however, those are not contiguous. Often defined previously as lava flows, etc., and used in the sense of a descriptive interval. Enumerated contiguously as Unit 1, 2, 3, etc. As defined here, units may correspond to one or more description intervals. Sedimentology: group of beds.
Descriptive interval 101~101 Primary descriptive entity that can be readily differentiated during time available. One row per interval in principal logging tab (lithology specific) Typically corresponds to beds. If beds are too thin, a thicker interval of “intercalated…” is created, and 2−3 domains describe the characteristics of the different types of thin beds. Typically corresponds to the lithologic unit. As defined here, a lithologic unit may correspond to one or more description intervals. Sedimentology: thinnest bed to be measured individually within a preset interval (e.g., 0.2 m, 1 m, 5 m, etc.), which is determined based on time available.
Domain Same as parent descriptive interval Additional rows per interval in principal logging tab, below the primary description interval row; numbered 1, 2, etc. (with description interval numbered 0) Describes types of beds in an intercalated sequence can be specified in detail as a group. Describes multiple lithologies in a thin section or textural domains in a macroscopic description. Feature description within descriptive interval, as needed.

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