1/2 Huaynaputina erupted in the area we are working in 1600 with volcanic explosivity index of 6, the largest historic eruption in South America. There is tephra everywhere. Some of it has been reworking into these amazing tephra dunes! #SFUNaturalHazards #PeruvianGeology 
2/2 The initial tephra fall was devastating to local communities, many being completely buried, with buildings collapsing as far away as Arequipa. Interesting taphonomy of this tephra, since even >400 years later the tephra is still being redeposited. #SFUNaturalHazards
1/2 More info on the tephra dunes. They can also form across small gullies like the one shown here. IN 2017 an unusual, intense rainfall event, triggered by el Nino, caused a lake to form behind the dam, the dame to fail and triggered a debris flow....more
2/2...which traveled down the road that was built in the stream channel. 5 people were killed. Here is video, warning it is disturbing:
That is a >400 year secondary volcanic hazard. Thanks to Rigoberto Aguilar, Ingemmet, for info and link
That is a >400 year secondary volcanic hazard. Thanks to Rigoberto Aguilar, Ingemmet, for info and link
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