Talk:Mendocino Fracture Zone

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Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 03:52, 17 January 2022 (UTC)

Inland extension

I deleted the passage relating to the possibility of an inland continuation of the Mendocino Fault as both obsolete (1965 is pre-plate tectonics) and erroneous. The Mendocino Fault definitely terminates at the triple junction. That is not to say that there may not be a tectonic zone extending inland which aligns with it. The alignment is there no doubt because of the drag and compression imparted by the descending Gorda Plate. There is speculation that this zone may eventually become part of the western tectonic boundary of the North American Plate as the Sierra-Great Valley Block breaks off (if it does) and either moves independently or as part of the Pacific Plate. The whole region is comprised of old terranes anyway, only "recently" and tenuously appended to the North American Plate, plus the rifting in the Great Basin is likely connected to the same mantle upwelling which was overridden by the North American Plate and has re-appeared as the East Pacific Rise "unzipping" up the Gulf of California toward the Great Basin. Tmangray (talk) 01:43, 14 March 2010 (UTC)

The concepts of Plate Tectonics and Continental Drift date to 1912 with Alfred Wegener and 1929 with Arthur Holmes.

Newer concepts do not invalid older data and observations. Rather, these concepts were built upon old data and observations compiled over several decades, and especially the 1960s. Without that data, the concepts of Plate Tectonics could never have been discovered.

Continental Drift and Plate Tectonics explain the context and the cause of the phenomena described by the old data and observations. However, if we reject data just because it is old, we have no right to the concepts upon which old data is based.

You describe the region as composed of old terrains, and indeed, it is. Extrapolating from the observations of Pease, using the concepts of Plate Tectonics, it is likely that the tectonic zone we're discussing was the surface boundary between the Gorda and Pacific plates that accreted onto the continental plate as the primary mass of these plates subducted.

That explains why this tectonic zone is no longer very active. In turn, the existence of this zone explains why the surface features of the Sierra Nevada and Walker Lane - the eastern plate boundary you mention - do not extend much beyond Honey Lake Fault.

There is much we can learn from applying the concepts of Plate Tectonics to the data and observations available to us, because all the observations exist in context with one another, and Plate Tectonics describes that context. For example, we may be able to learn from the context whether Walker Lane represents a future plate boundary, or a plate boundary of the past. However, we will not learn that, if we reject the context in which it exists.

Wikipedia editors do not remove sourced information from articles as "erroneous" or "obsolete". If they provide a reliable source for a differing point of view, they may add the differing point of view to the article. See http://en.wikipedia.org/wiki/NPOV

Therefore, I am reverting the deletion. Downstrike (talk) 03:26, 14 March 2010 (UTC)

The modern version of plate tectonics did not exist before about 1967. There was definitely no concept of a "triple junction" before then. The current view terminates transforms such as the Mendocino at the Mendocino Triple Junction. It does not extend past it.Tmangray (talk) 20:44, 14 March 2010 (UTC)

I have no doubt that the Mendocino Transform Fault currently terminates at the Mendocino Triple Junction. However, that does not address prehistoric conditions, which are part of the context in which these plate boundaries exist. That context is what you have deleted.

Deletion of encyclopedic content from Wikipedia articles just because it is historical or you believe it is erroneous, is in violation of Wikipedia guidelines for NPOV:

All Wikipedia articles and other encyclopedic content must be written from a neutral point of view, representing fairly, proportionately, and as far as possible without bias, all significant views that have been published by reliable sources. This is non-negotiable and expected of all articles and all editors. - http://en.wikipedia.org/wiki/NPOV

If you continue to violate this guideline, it will be reported.

However, as a compromise, I am placing the deleted content in a History section. Downstrike (talk) 06:18, 15 March 2010 (UTC)

The new edit reads far better than the previous one. It could be fleshed out though, perhaps with some mention of the evolution of the current situation i.e. arrival of terranes, evolution of the San Andreas, etc. Tmangray (talk) 21:10, 15 March 2010 (UTC)

Article Needs Citations

A recent deletion brought this to my notice; after the deletion, this article had NO citations left. Downstrike (talk) 03:37, 14 March 2010 (UTC)

The references for this article consist for now of the "external links" which will take you to numerous sources. The article on triple junctions explains the termination of transforms like the Mendocino. Tmangray (talk) 20:58, 14 March 2010 (UTC)

External links are to help users to find additional information. They are not citations:

Any material challenged or likely to be challenged, and all quotations, must be attributed to a reliable, published source using an inline citation. This applies to all articles, lists, and sections of articles, without exception. - http://en.wikipedia.org/wiki/Wikipedia:Verifiability

Here is a tool that anyone interested in this article may use to correctly format inline citations for most sources: http://toolserver.org/~magnus/makeref.php Downstrike (talk) 06:18, 15 March 2010 (UTC)

This is all technically correct, but too legalistic. In fact, most of the external links are academic sites, hence having far more credibility as references than many typical inline cites. One can safely assume that the geology departments of the various colleges and universities which produce these sites have ample reliable sources for what they say. Tmangray (talk) 16:39, 17 March 2010 (UTC)

They are ideal sources for citation. Downstrike (talk) 20:33, 17 March 2010 (UTC)

Add map showing true length

The Mendocino Fracture Zone is ... over 4000 km (2500 miles) long

Alas the map used shows it as much shorter. Jidanni (talk) 14:26, 25 June 2022 (UTC)