Talk:Stratum

Untitled
That was fast :-) _Vsmith 15:53, 15 Nov 2004 (UTC) short but sweet 217.178.78.85 (talk) 00:12, 6 October 2021 (UTC)

Merger proposal
I am proposing to merge Bed (geology) and Lamination (geology) into Stratum. From what I can tell, "bed" and "lamination" are generally used to describe the thickness of strata. Each of these three articles repeat much of what the others say, and merging them into one would create a much more comprehensive overview of the subject. CrunchyRocks (talk) 01:59, 2 February 2022 (UTC)

Preliminary discussion took place at the WP Geology talk page. CrunchyRocks (talk) 02:11, 2 February 2022 (UTC)


 * Support -- combined article will be much stronger than the current individual articles. Right now, we're not doing our readers a service by having these multiple articles. — hike395 (talk) 15:45, 3 February 2022 (UTC)


 * Support Oppose -- As defined in the American Geosciences Institute's "Glossary of Geology," a "stratum" is the primary unit of classification for a layer of rock / sediment of which a "bed" is a subdivision. Thus, a bed and a stratum are not the same geologic entity with a stratum being composed of / divisible into multiple beds. The combined article would be an appropriate place to discuss a "bed" as being a subdivision of a "stratum." Paul H. (talk) 19:01, 5 February 2022 (UTC)
 * This is a "thorny issue," with multiple definitions for both terms that I need to look into more. It might be too much to address the multple meanings of both terms in a single article. I am changing my vote to "oppose." Paul H. (talk) 21:37, 5 February 2022 (UTC)


 * Comment - I have access to digital versions of books on sedimentology and and geology. I did a search and word count in each of them for “bed,” “beds,” “bedding,” “stratum,” and “strata.” Some results:


 * 1 Allen, P. A., and Allen, J. R., 2013. Basin Analysis: Principles and Application to Petroleum Play Assessment, Wiley-Blackwell, Inc.
 * bed (133), beds (67), bedding (2), stratum (0), and strata (31)


 * 2. Galloway, W. E., and Hobday, D.K., 1996. Terrigenous Clastic Depositional Systems Applications to Fossil Fuel and Groundwater Resources, Springer-Verlag.
 * bed (274), beds (218), bedding (135), stratum (3), and strata (111)


 * 3. Einsele, G., and Seilacher A, 1982. Cyclic and Event Stratification. Springer-Verlag
 * bed (298), beds (621), bedding (244), stratum (2), and strata (31)


 * 4. Middleton, G. V., 2003. Encyclopedia of Sediments and Sedimentary Rocks. Springer-Verlag
 * bed (941), beds (621), bedding (317), stratum (7), and strata (184)


 * 5. Boggs Jr., S., 2009. Petrology of Sedimentary Rocks. Cambridge University Press
 * bed (65), beds (159), bedding (175), stratum (0), and strata (31)


 * 6. Jain, S., 2014. Fundamentals of Physical Geology. Springer
 * bed (64), beds (29), bedding (28), stratum (4), and strata (37)


 * 7. Woods, K. M., 2009, Physical Geology Laboratory Manual. Kendall/Hunt Publishing.
 * bed (8), beds (13), bedding (6), stratum (7), and strata (44)


 * 8 Stow, D. A. V., 2010. Sedimentary Rocks in the Field: A Colour Guide. Manson Publishing
 * bed (162), beds (126), bedding (204), stratum (0), and strata (16)


 * 9. Davis, G. H., Reynolds, S. J., and Kluth, C., 2012, Structural Geology of Rocks and Region. John Wiley & Sons, Inc
 * bed (293), beds (198), bedding (396), stratum (1), and strata (207)


 * The number of times that “bed” is used in some of these texts is inflated because it also refers to a surface, “river bed” or “sea bed” on which sediments accumulated. Even if that is allowed for it looks like “bed,” “beds,” and “bedding” are overwhelmingly prefered to “stratum” in usage. Paul H. (talk) 16:06, 6 February 2022 (UTC)


 * Comment - Ok, looking at this again I can see that a merge is not really the obvious solution. I'll instead work on improving the individual articles and see where it goes from there. This is a topic with some ambiguous definitions and boundaries, which will hopefully become more clear with improved articles. CrunchyRocks (talk) 20:32, 10 February 2022 (UTC)

and another thing
Within North American Stratigraphy (potentially a limited context within the global context of WP), ranking and naming of geologic units is regulated by the North American Stratigraphic Code and bed has specific meaning, whether as formal or informal classifications. The specific meaning is no less than the fundamental principle of stratigraphy in that all geological classications are compositions of beds:

Although WP says that Stratum "is the fundamental unit in a stratigraphic column", the Code makes little use of the term other than


 * 1. A lithostratigraphic unit is a stratum or body of strata, generally but not invariably layered, generally but not invariably tabular, that conforms to the Law of Superposition and is distinguished and delimited on the basis of lithic characteristics and stratigraphic position.

But holds much use of bed throughout the Code:
 * (d) Division of members.—A formally or informally recognized division of a member is called a bed or beds, except for volcanic flow rocks, for which the smallest formal unit is a flow. Members may contain beds or flows, but may never contain other members.
 * Article 26.—Bed(s). A bed, or beds, is the smallest formal lithostratigraphic unit of sedimentary rocks.
 * (a) Limitations.—The designation of a bed or a unit of beds as a formally named lithostratigraphic unit generally should be limited to certain distinctive beds whose recognition is particularly useful. Coal beds, oil sands, and other beds of economic importance commonly are named, but such units and their names usually are not a part of formal stratigraphic nomenclature (Articles 22g and 30g).
 * (b) Key or marker beds.—A key or marker bed is a thin bed of distinctive rock that is widely distributed. Such beds may be named, but usually are considered informal units. Individual key beds may be traced beyond the lateral limits of a particular formal unit.
 * (b) Key or marker beds.—A key or marker bed is a thin bed of distinctive rock that is widely distributed. Such beds may be named, but usually are considered informal units. Individual key beds may be traced beyond the lateral limits of a particular formal unit.

Some beds are formally named within the North American Stratigraphic lexicon (Back Bed), but many are not (Ostrea beloiti bed of the Graneros Shale).

Lamination is distinct from beds. Lamination is a type of facies that a bed may or may not have. To be classified, a bed must be described. Some shale and sandstone beds are described by their characteristic lamination, while other shale and sandstone beds are described by their characteristic absence of lamination.

River and ocean beds are a completely different things from stratigraphic beds. Many of the sandstone lenses of the Dakota Formation were formed by laminated deposition of sand in a river bed, but they are not stratigraphic beds because, being restricted to river beds, they have no useful wide distribution.

IveGoneAway (talk) 02:16, 12 February 2022 (UTC) 17:17, 12 February 2022 (UTC)

"Substratum" listed at Redirects for discussion
The redirect [//en.wikipedia.org/w/index.php?title=Substratum&redirect=no Substratum] has been listed at redirects for discussion to determine whether its use and function meets the redirect guidelines. Readers of this page are welcome to comment on this redirect at  until a consensus is reached. fgnievinski (talk) 19:43, 11 August 2023 (UTC)