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I think it does make sense add Geology / Hydrology / Geophysics as categories, but don't know how to do that. E70s (talk) 18:37, 23 May 2012 (UTC)[reply]

Would this page belong in a category like Geology or Geophysics? -- MJSkia1 02:33, May 22, 2005 (UTC)

Well, maybe it can not merge. But it shouldn't be deriving Darcy's law. I'd be happy if it looked more like Newton, or similar page for a unit of measure.Mwtoews 17:48, 27 July 2006 (UTC)[reply]

As the article says, "[t]he darcy is defined using Darcy's Law ... ." It doesn't make sense in other contexts --- unlike forces. Also, in the Newton article, the definition implicitly uses F=ma but doesn't say so outright. Neither article is deriving the underlying law, just using it.

Permeability can also be measured in other units such as meters squared, centimeters squared, barns, or any other unit of area; you wouldn't merge those into the article on Darcy's law, right? Perhaps it would make you happier to mention that the Darcy is an effective cross-section? Lunch 21:23, 27 July 2006 (UTC)[reply]

Agreed. I'll remove the merge tag, and massage this article to be more about the unit, and some application of Darcy's law. I'll do that some day later. I'll also add a handy conversion table (like the Newton article). Mwtoews 00:13, 28 July 2006 (UTC)[reply]

It would be nice if this page had, or linked to, some example scenarios with estimated permeability in millidarcies or whatever. I came here curious about that, so I'm not qualified to write it (yet).

Defiler (talk) —Preceding undated comment added 19:30, 27 June 2010 (UTC).[reply]

Oops... I should have read the page in more detail before jumping to conclusions... my apologies. I am stunned by the AAPG style guide reference claiming that Darcy should not be capitalized. I'll spend some more time researching this topic and won't make any edits until I have a solid reference to base them on. E70s (talk) 18:44, 23 May 2012 (UTC)[reply]

It is my understanding that the unit "Darcy" should always be capitalized, precisely because it is named after Henri Darcy. It's the same as with the unit for force, "Newton", is always capitalized ("N"). I edited the page throughout to reflect this. It has been something that has bothered me in some of the porous media flow literature, so please either prove me wrong or help get rid of this typo. E70s (talk) 18:37, 23 May 2012 (UTC)[reply]

I would agree with the statement that it should be capitalized. It's not an SI unit and the only industry that still uses it (oil & gas), abbreviates it as D or mD and so the industry standard should be the standard. 63.84.120.210 (talk) 20:09, 8 June 2023 (UTC)[reply]

The AAPG style guide is now a dead link - if anyone knows an alternative source please replace it 195.59.47.132 (talk) 14:37, 7 March 2016 (UTC)[reply]

An archived link to the AAPG style guide has been resolved, in addition they have a Wiki, where they use both "Darcy" and "millidarcy". Looking through the literature, I do not see "milliDarcy", just "millidarcy", which implies "darcy". USGS use "darcy" in this 1986 report. Streltsova, 1976 doi:10.1029/WR012i003p00405 explicitly define in an appendix "A unit used in the petroleum industry, darcy, has the value of 0.987 × 10⁻⁸cm²". This is the earliest definition I can see (without looking too deep). While I think it's okay to have "Darcy" here, it appears to be more formally defined in the literature as "darcy". +mt 03:34, 6 October 2016 (UTC)[reply]