Talk:Bed (geology)

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"Laminae" are actually the smallest on the scale of depositional layering Awickert (talk) 05:26, 15 July 2008 (UTC)

In geotechnical terms laminae are just fine scale beds. I've logged core in which the laminae were only visible with a good hand lens and we used the term micro-laminated. The full scale was; very thickly bedded (>2m), thickly bedded(600mm to 2m), medium bedded(200mm to 600mm), thinly bedded(60mm to 200mm), very thinly bedded(20mm to 60mm), thickly laminated(6mm to 20mm), thinly laminated(2mm to 6mm), very thinly laminated(0.6mm to 2mm) and microlaminated(<0.6mm). This extended the standard BS 5930 (1999) scheme at the thinner end by two divisions. I should probably add something about this. Mikenorton (talk) 09:37, 15 July 2008 (UTC)

Wow - sorry for not getting back for so long. In geological terminology, a "bed" is colloquially used for everything, but there is an official distinction between bed and lamina at around 2 cm, I believe. But if this doesn't cross into other fields, maybe it's a semantic issue that's not worth pursuing. Awickert (talk) 00:40, 2 October 2008 (UTC)

References

• Boggs, S. Jr., "Principles of sedimentology and stratigraphy 3rd. ed". Prentice-Hall, Upper Saddle River, New Jersey: 726 p.

— The study of beds sequenced as layers on top of other beds.

• Campbell C. V., Lamiae, laminaset, bed and bedset: Sedimentology v8, p7-26

— Difference in the sizes of beds and terminology of them.

• Einsele G., Ricken W., and Seilacher A., "cycles and events in stratigraphy", Springer-Verlag, Berlin, Heidelberg, New York 1991. 955p.

— Sedimentary's cycle in formation with similar lithology.

• F.L. Ladeira, N.J.Price, "Relationship between fracture spacing and bed thickness", Journal of Structural Geology, Vol. 3, No. 2, pp. 179 to 183, 1981. https://www.sciencedirect.com/science/article/pii/0191814181900134

— How the thickness of a bed is affected by the beds of layers adjacent.

• Ingram, R.L., Terminology for the thickness of stratification and parting units in sedimentary rocks. Geol. Soc. Bulletin, 65: 937-938.

— Different bed thicknesses and their terminology.

• Lyell, C., Principles of Geology volume 1, pp 511

— Bedding structures and uniformitarianism.

• Schlager, W., Fractal nature of stratigraphic sequences. Geology, 32(3): 185-188.

— The order of stratigraphic sequences — Preceding unsigned comment added by Tenzinsonam995 (talk • contribs) 04:14, 22 April 2018 (UTC)

Difference between "bed", "stratum" and "layer"?

Do geologists make a distinction between these three words? The article currently starts by saying "Beds are the layers of sedimentary rocks ... Layers of beds are called strata." Does that make sense? I can't find clear definitions of these words. UBJ 43X (talk) 20:53, 23 March 2020 (UTC)

Bedding plane

The article uses the term "bedding plane", which is redirected to this article, but never defines it. A definition is badly needed.Bill (talk) 19:27, 13 September 2020 (UTC)

Bed thickness

The bed thickness descriptions do not match with those in use at least in the UK, EU and Australia - in BS 5930 see page 135 or its equivalents ISO 14689-2017 and AS1726, the boundaries between bedding scales are:

• Very thickly bedded >2 m
• Thickly bedded 600 mm -2m
• Medium bedded 200 mm - 600 mm
• Thinly bedded 60 mm - 200 mm
• Very thinly bedded 20 mm - 60 mm
• Thickly laminated 6 mm - 20 mm
• Thinly laminated <6 mm

I'm not sure about other standards around the world, but the one used in the article may be only in the US. Mikenorton (talk) 20:36, 21 February 2022 (UTC)

Thanks for the helpful information. Hopefully, that oversight has been fixed. Paul H. (talk) 14:29, 26 February 2022 (UTC)