Talk:Franciscan Complex

Serpentinite is Not schist, in this area it is directly related to plate subduction , metamorphism and related plate and local tectonics, the rock groups are completely different in age and composition along both sides of the plate boundaries, makes it easy to remember where you are when field mapping, Local geology 101 CA is a tortuous geological mess And will never be perfectly solved, Btw, Maybe you could take Better geological photos not including your girl friend and more inclusive geolocical Importance of your intent of study Btw Serpentinite is the State rock, which i believe was a very poor choice rather picking granodiorite instead And there is plenty of that located well beyond unstable mushed plate boundary rock sequences, Although i do admire serpentinite's greenish hues and slickensided Nature attesting to its tortued uplift, Suggest discussing the elements of plate tectonics, which was a very controversial subject in the mid 1970s

Prehistoric tools section removed

I removed this section:

Archaeological recovery of Franciscan chert prehistoric tools from Native American sites in the western USA acknowledges the use of Franciscan material as a diagnostic indicator of rock source and thus the presumption of ancient trading patterns among tribes. For example finds of Franciscan chert in Central California suggest extensive trade between tribes of the San Francisco Bay Area with Chumash peoples.

While it is certainly possible that there was "extensive trade between tribes of the San Francisco Bay Area with Chumash peoples", this is not supported by the reference -- [1] -- which says nothing of trade. San Luis Obispo County has abundant outcrops of Franciscan rocks, including the Morro Bay area, the subject of the reference. Anyone feel free to put this paragraph back if there is a better reference, i.e. one that specifically traces that particular chert to the San Francisco Bay Area. (The first sentence of the paragraph may indeed be true; we just need a different example.) Cheers, Antandrus (talk) 04:40, 6 October 2010 (UTC)

Oldest ages in JKf are circa 170 Ma (certain high grade metamorphic blocks). Most is Cretaceous (145-65 Ma) but the King Range terrane on Mendecino coast is as young as Miocene. However, the Marin Headlands terrane contains oceanic cherts as old as about 200 Ma. Don't have time edit now, maybe over Xmas. Geodoc (talk) 03:24, 6 November 2011 (UTC)

References

Controversies related to "defining the architectural units of Franciscan Complex"

Should this be added to the article as a sub section under Description Meghomita (talk) 17:36, 13 September 2019 (UTC)

yes good idea Christierowe (talk) 16:08, 17 September 2019 (UTC)

Controversies related to "defining the age problems in Franciscan"

Should this be added as a subsection under Geological History Meghomita (talk) 20:28, 13 September 2019 (UTC)

yes good idea Christierowe (talk) 16:12, 17 September 2019 (UTC)

Title of article should be Franciscan Complex

The "assemblage" is not modern stratigraphic nomenclature Christierowe (talk) 16:08, 17 September 2019 (UTC)

Trying to update the Description and Geological History Section

Trying to update the Description and Geological History section with more updated references from journal articles. Will add some new pictures to highlight the rock types and outcrops of the Franciscan. The lead section and the information box will also be updated to include the above mentioned changes Meghomita (talk) 19:44, 7 November 2019 (UTC)

The new updated version of the Description and Geological History section has been added. Major inclusions are more updated references from books and journal articles. Pictures (courtesy of AGU, Callan Bentley, and Christie Rowe) are added to the article to highlight the rock types and outcrop features and structures of the Franciscan. Minor changes to the lead section and information box include a better summary description of Franciscan and the addition of greywackes and serpentinites in the rock description. DOI, ISBN, ISSN, and other external links are added to the Reference list section to improve accessibility to the article. Meghomita (talk) 19:08, 16 November 2019 (UTC)