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Line 66: − − [[file:core-description_fig2.png|thumb|{{figure number|2}}(a) Comparison chart for sorting and sorting classes. (Modified from <ref name=pt05r125>Pettijohn, F. J., Porter, P. E., Siever, R., 1987, Sand and Sandstone, 2nd. ed.: New York, Springer-Verlag, 553 p.</ref>.) (b) Comparison chart for roundness and sphericity. (Modified from <ref name=pt05r130>Powers, M. C., 1953, A new roundness scale for sedimentary particles: Journal Sedimentary Petrology, v. 23, p. 117–119.</ref>.)]]
→Format for core logging
===Accessories===
===Accessories===
[[file:core-description_fig2.png|thumb|{{figure number|2}}(a) Comparison chart for sorting and sorting classes. (Modified from <ref name=pt05r125>Pettijohn, F. J., Porter, P. E., Siever, R., 1987, Sand and Sandstone, 2nd. ed.: New York, Springer-Verlag, 553 p.</ref>.) (b) Comparison chart for roundness and sphericity. (Modified from <ref name=pt05r130>Powers, M. C., 1953, A new roundness scale for sedimentary particles: Journal Sedimentary Petrology, v. 23, p. 117–119.</ref>.)]]
Fossils, trace fossils, diagenetic and structural features, and other accessories are shown on the far right side of the left column of a graphic log. Standard symbols for these features are found in Swanson<ref name=pt05r150 /> and Bebout and Loucks.<ref name=pt05r24 />
Fossils, trace fossils, diagenetic and structural features, and other accessories are shown on the far right side of the left column of a graphic log. Standard symbols for these features are found in Swanson<ref name=pt05r150 /> and Bebout and Loucks.<ref name=pt05r24 />
Dominant lithologies and the nature of the contact between lithologic units are recorded in the “Rock Type and Contacts” column near the middle of a graphic log ([[:file:core-description_fig1.png|Figure 1]]). Standardized symbols for illustrating lithologies are available and are presented by Tucker<ref name=pt05r157>Tucker, M. E., 1982, The Field Description of Sedimentary Rocks: United Kingdom, The Open University Press, 112 p.</ref> and Lindholm.<ref name=pt05r103 /> If more than one lithology or interbedded lithologies exist within an interval, lithologies should be logged by estimating the percent volume of each lithology and noting the terrigenous clastic lithologies to the left of the chemical rocks. Contacts between lithologies are recognized in core as gradational, interbedded, or sharp. Some sharp contacts are probably erosional and may represent unconformity surfaces. Additional information such as the presence of root structures and early diagenetic cements may aid in determining the true nature of sharp contacts.
Dominant lithologies and the nature of the contact between lithologic units are recorded in the “Rock Type and Contacts” column near the middle of a graphic log ([[:file:core-description_fig1.png|Figure 1]]). Standardized symbols for illustrating lithologies are available and are presented by Tucker<ref name=pt05r157>Tucker, M. E., 1982, The Field Description of Sedimentary Rocks: United Kingdom, The Open University Press, 112 p.</ref> and Lindholm.<ref name=pt05r103 /> If more than one lithology or interbedded lithologies exist within an interval, lithologies should be logged by estimating the percent volume of each lithology and noting the terrigenous clastic lithologies to the left of the chemical rocks. Contacts between lithologies are recognized in core as gradational, interbedded, or sharp. Some sharp contacts are probably erosional and may represent unconformity surfaces. Additional information such as the presence of root structures and early diagenetic cements may aid in determining the true nature of sharp contacts.
===Maturity===
===Maturity===