Fushimi Inari-taisha, Kyoto is the shrine dedicated to the spirit of the Fox (Inari). Inari is also the kami of fertility, agriculture, and industry, as well as of many products that are typical of Japan, like sake, rice, and tea. A main shrine existed here since 711, but the main buildings date back to the year 1499.
This place, sacred to the Shinto, draws every year millions of worshippers -especially during the Japanese New Year – and tourists. The place is popular not only for its beauty, but also because of the thousands of torii gates scattered over the path through the forest that guide the visitor to the summit and the other minor shrines that are present in the woods.
Passing below this path of torii really is a magical and evocative experience. The feeling is to be protected, while being in the woods at the same time! The path winds along the mountainside and make many deviations and forks to small shrines, temples, forest paths, and protected alcoves with street food sellers preparing delicious Kyoto-style hashimaki. The good aroma they diffuse through the forest makes the 2 hour ascent to reach the 233 meters summit really challenging, but the views towards the top are really rewarding!
This place is really silent, beautiful, and edvocative. Beyond the panorama, there is something else you may see around while wandering in the labyrinth of trails. In this area there are, indeed, really weathered outcrops of folded layers of chert e mudstone.
The outcrops are honestly badly weathered and mostly covered, but the few things that you can see testify a really complicated geological history. Above you can see cherts (the thick layers) surrounded by foliated claystones. The folds are really disharmonic and chaotic and, if you follow the cherty layers, some appear to be disrupted.
I would personally call this chevron folds, as in most cases the bend is abrupt and concentrated on the hinge. However, in many places they appear a bit irregular and more curvy than the average chevron fold. It is really difficult to follow many of these layers, as in places they are fractured and do not appear to continue much laterally. I was curious and I checked the geological map of the area (that you can find here). This is also a nice opportunity to test the slider with geological maps:
As you can see in the map, most of the rocks in the area constitute small, isolated and deformed bodies that are surrounded by a mudstone matrix: the whole area exposes an old Jurassic – Cretaceous mélange. Mélange is a fancy French term to say ‘mixture’ or ‘medley’, which exactly represents what this these rocks are: a big mess! Japan currently sits on a subduction zone, where the Pacific Plate slides below the Eurasian margin. When oceanic crust slides down, tectonic forces scrape sediments and rocks off the undergoing slab. The process can be accompanied by sudden earthquakes and rapid tectonic movements that cause the disruption of the original lateral continuity of layers that end up incorporated in soft material like mud, as it is the case. As this was not enough, landslides may occur in such margins and cause the deposition of mixtures of exotic, disrupted blocks in a muddy matrix on the subducting slab, before it enters the subduction zone. Mélange-forming processes have been going on in the Japanese Islands for the last 450 million years. The compressional regime acting here has continued to push the accreted mélange rocks upward… so that you can get a glance of the turbulent tectonic history that has shaped this country and continues to shape it today.
Riferimenti bibliografici
Geologic Map of Kyoto.
Geological Survey of Japan.