In the continental crust, minerals with a small molecular weight are on the surface (calcium, carbon...), and with a large molecular weight (gold, mercury...) in the deep layers. For this reason, deposits of heavy minerals on the Earth's surface are located in areas of cracks in the earth's crust. This is primitive, but that doesn't mean it's false.

Сложно поставленный вопрос, с точки Логики.

Геодинамика входит в понятие "тектоническая обстановка"? Тогда связано. А если собственно ("просто") "тектоническая обстановка" -- то она индивидуальна -- иногда связь очевидна (связь с разломами, ...), а иногда "как бы и не связана" (для крупных геологических тел).

По моим представлениям, тектоническая обстановка есть результат геодинамических процессов, следовательно, последние (если их сузить даже лишь тектонические движения) порождают "механику перемещения флюидов" (в том числе "рудоносных") и, соответственно, перераспределения "рудообразующих составляющих", и, в результате, формирование рудоносных тел.

Но это лишь часть процесса рудообразования. По результатам моих исследований, растворение-перенос-осаждение=концентрация рудного составляющего обусловлено именно электрическими явлениями в Земной коре, которые неизбежно возникают благодаря тектоническим движениям...

У меня тоже большой стаж непрерывной работы по сходной тематике (неотектогенез) (с 1986 г.). Удачи!

Hope you know "Mineral System Analysis"----a relatively new concept.

You need accommoditon space provided by tectonic to vent magma and concentrate minerals of economic grade.

There is no doubt about

HGD

Depending on the deposit type, yes.

Harald G. Dill My naive understanding was there is a distinction between 'tectonic' surface vulcanism driven by the crust thinning and thickening caused by plate movement, and 'non-tectonic' surface vulcanism where a plate ( moving or not ) is over a mantle hot spot - while the current surface vulcanism is occurring in a given region, these have left large long swathes across the plates.

Considering the term 'ore' in general, isn't concentration ( or diffusion ) potentially the result of many types ( and sequences ) of geochemical, geothermal (not necessarily volcanic), biological, and mechanical ( erosion dispersal and fluvial consolidation ), etc.? Even just considering metals, and ignoring all the other useful minerals, 'Bog Ore' comes immediately to mind:Article Bog iron ore as a resource for prehistoric iron production i...

For instance, an almost purely geologic 'milling' sometimes occurs with glaciers: https://www.jstor.org/stable/30064717 and non-magma geothermal concentration can occur in folding situations: Article Enrichment of iron ores by folding in the BIF‐hosted deposit...

One might make a case that for most of human history, until "De re metallica" ( https://echo.mpiwg-berlin.mpg.de/ECHOdocuView?url=/permanent/library/5CTEBAHQ/index.meta&viewMode=image&pn=5&viewLayer=dict ) humans harvested the low hanging fruit of these non-magma mineral concentrations.

Yes, I agree that the Tectonic environment, is only one of many factors that produce ore minerals. In my mind, it is the associated fluids and their origin and movements, that are the main factors. However, it is the overriding tectonic setting that determines which solutes and fluids are associated. It is the hydrothermal systems that cause ore minerals to be deposited.

Dear Dr. Patrick,

you started with an "opus" De re metallica libri XII" a compilation of Georgius Agricola which gives an extensive overview of the past time mining activities time before 1556. Many methods are still in use albeit refined.

Given the so-called hotspot mantle magmatic activity does not work its way up without deep-seated faults involving strike-slip or simple extension fault, e.g., the Canary Islands Archipelago. There is not such a "welding torch" or deus ex machina at depth which is venting a magma and pouring out as a lava without fractures in the crust. Volcanic activity in context with structural geology acts as a powerful couple in forming ore deposits. Even these seemingly infertile hotspot volcanoes can bring about interesting ore mineralizations, particularly of the so-called-critical-element suite.

Ore is a well-defined term in mining and exploration. It is first and foremost a rock consisting of gangue (trash) such as quartz or carbonates and ore minerals from which by means of the existing methods of mining, mineral processing and smelting metals can be extracted at a profit. A micro-mount in the showcase is not an ore by definition.

Bog iron ore is a sedimentary Fe ore which was in historic times mined in Scandinavia and norther Central Europe after the retreat of the large inland glaciers. It form under near ambient conditions in lacustrine environments under oscillating water tables giving rise to Fe ore bearing "Fe-Mn limonite" a mixture of easy to process and smelt Fe-Mn minerals of poor crystallinity.

Milling of glaciers, BIF (Banded Fe Formation) and geothermal activity is a bit of mineralization cocktail which I would not like to offer to anybody. In principle it is a mixture of sedimentary, magmatic and metamorphic ore deposition located far apart from each other.

I have been giving lectures and field training in economic geology and mineralogy from Al to Zr since 1981 until today. If you want to know something more about this kind of applied geosciences browse my list of publications on Researchgate and I will be happy to forward to you some digital prints upon request.

For now I hope that I was able to clarify some issues

Glückauf!

HGD

Ore deposits of economic value are formed under varied geological conditions. Two groups of ore deposits may be established syngenetic and epigenetic depending on their formation time relationship to the rocks associated with them (Robb, 2005). Syngenetic mineral deposits are formed at the same time as the associated rocks as in magmatic segregation during the orthomagmatic stage of consolidation of magma or during precipitation of sedimentary rocks. Formation of ore deposits in gossans and laterites due to in situ residual gossans are also considered as syngenetic because as the new rock (laterite, bauxite, kaolinite, or duricrust) is formed it is at that same time the ore deposit is formed.

The epigenetic mineral deposits are formed later after the enclosing or host rocks have been formed in filled or opened fissures in the country rocks and such ore bodies are called lodes or veins. These vein and lode deposits occur as in interstices of the country where the rock forms first and then ores form as impregnations or replacements of the country rock. In contact metamorphism mineral deposits form irregular ore bodies on the margins of metamorphosed rocks. In sedimentary rocks epigenetic processes, ore deposits are formed due to weathering and deposition of detrital sedimentary rocks in basins where placer deposits are emplaced

Harald G. Dill Thank you for the detailed reply! I picked De Re Metallica because it seemed to represent a point where mining transformed from an artisanal activity into an actual industry with a common body of knowledge ( https://www.gutenberg.org/files/38015/38015-h/38015-h.htm#APPENDIX_B ). I have had occasion to reference it to find inspiration, not necessarily for mining, but situations where folks in remote locations are moving and processing a lot of dirt and rocks with minimal resources found on site.

And thank you for pointing me to your papers, to this point my knowledge of actual geology has been tangential and peripheral, because my main interest is automated feature extraction, so for about how rocks stick out and pile up than what's inside them. :-)

Off course, tectonic environment does not independently control ore deposit but tectonism are usually the begining or initiator of many. Have you consider biological activities, ocean and climate situation? In the case of Fe deposit , Mn deposit etc.

There probably needs to be heat flow involved and also plenty of NaCl fluids (salts). Normally these would come up from the mantle, as they have been brought down deep during subduction processes.

Directly, may be yes. Indirectly, may be no. I think the sedimentary environments are completely controlled by direct and indirect factors, that are guided and shaped by regional tectonics.

All you should know and discuss about Mineral System Analysis. Tectonics does directly or indirectly control mineral deposit formation.