Template talk:Hadean footer

Should this template be deleted?

I think that this template should be deleted. No one in the lunar community uses the term "basin groups" or "Hadean". Basin groups and "Imbrian" are never applied to the Earth either. Lacking a good rationale for keeping this, I will soon put this template up for deletion. Lunokhod 18:48, 14 January 2007 (UTC)

• I can understand that at present the subdivisions of Pre-Nectarian time into Basin Groups Stage and Cryptic Stage are more theoretical than real, since we don't have adequate samples or appropriate techniques for dating right now. Nonetheless, these two stages have been with us for at least 17 years if not longer, and I see no need to put them on the trash heap. Wikipedia reports what is in the literature, not necessarily what is practical for a practicing selenologist. See Harland, Walter Brian , et al. (1989) A Geologic Time Scale 1989 Cambridge University Press, Cambridge, UK, Fig. 1.7 on page 10 and the appropriate entries in the GeoWhen database, footnoted in the table in the Geologic Timescale article. The ICS has not deigned to address subdivisions to the Hadean, but the lunar subdivisions have been applied in general to the Hadean. The template is clearly so marked. --Bejnar 03:25, 16 January 2007 (UTC)
• At 10:40, 16 January 2007, Lunokhod removed the subdivisions of this template with the comment on the edit line "{You can not "paste" parts of the lunar geologic timescale into the Earth one. This is really bizarre. Why not use the Martian geologic time scale instead?)".

I did not graft lunar timescale onto the Earth. I am only reporting what has happened in the literature. We do not do original research here. If you find it bizarre that some people in the field of geology have decided that the early histories of the Moon and the Earth are close enough to each other that the same time scale is appropriate, take it up with them in the appropriate forum, which is not Wikipedia. It is not the first time this sort of thing has happened; the Devonian was first established in England, but that did not stop geologists from using it in the New World. As editors we don't dictate what goes into science, we report what scientists say, in their publications. Please do not remove properly cited reliable information. If you believe that GeoWhen Database and Harland's A Geologic Time Scale 1989 are not reliable reports of what is going on in the field of geology (not selenology), then let us discuss that, and not engage in removal of material until and unless we can reach agreement. --Bejnar 18:34, 16 January 2007 (UTC)

• I agree with Lunokhod, it is questionable to use lunar geological periods in the terrestrial timescale, especially if there are no other sources.--JyriL ^talk 18:55, 16 January 2007 (UTC)

• If the proposal to delete Basin Groups passes, we will have to take care of this in one of two ways: (1) propose this template for deletion, or (2) modify it so that if reflects the vast majority opinion of terrestrial geologists. Does anyone have an idea on how we could "fix" this template? Lunokhod 19:23, 16 January 2007 (UTC)

The template is to make navigation between articles easier. If there is only one article about the Hadean eon, then there is no point having a footer for the eon.--JyriL ^talk 19:31, 16 January 2007 (UTC)

I agree, if no one uses subdivisions of the Hadean eon anymore, then such historical (see Harland) use can be a line or two in the Hadean article, and there will be no need for a Hadean footer. That time is not yet. --Bejnar 01:58, 17 January 2007 (UTC)

USGS

How can it be said that the USGS doesn't recognize the Hadean when it is a term both in their Thesaurus and a search term in GEOLEX? --Bejnar 03:35, 17 January 2007 (UTC)

The geologic time scale that they have on line here is actually based on the version of the published by the GSA, which only includes the Archaen, but not Hadean. Your right, though, that this probably doesn't represent a formal endoresement.Lunokhod 11:08, 17 January 2007 (UTC)

Harland et al.'s subdivions of the Hadean

It appears that these subdivions of the Hadean come from Harland et al. (1989). In the text, he advocated using the lunar geolocic time scale for the Hadean period, which inludes the Pre-Nectarian, Nectarian, and Lower Imbrian periods. He then notes that the pre-Nectarian has been subdivided into Cryptic, Basin Group 1, and Basin Groups 2-9 by Wilhelms (1987). However, when you look at his figure, he only showed the subdivisions of the Pre-Nectarian (i.e., Cryptic and Basin Goups), but not the Pre-Nectarian itself. The only way that I can interpret this inconsistency is that the figure contains an "typo."

Thus, if we are to keep this template (which I would prefer not too because using the lunar geologic time scale for the Earth is a very minor opinion in the scientific literature) I suggest that Cryptic and Basin Groups be replace with Pre-Nectarian, as per the original proposal of Harland et al. (1989). Otherwise, I will insist that this be given a citation from a reputable source, which does not include the Harland et al. book.

I highly suggest that those interested read the Harland et al. book. I am certain that you will come to the same conclusion. Lunokhod 15:22, 20 January 2007 (UTC)