the fire in 1988 damaged it and also the geysers and hot springs can be damaging
intraplate setting
Yes. I'm not sure about continental US, but Hawaii, having been formed by volcanic activity, has plenty of igneous rock. Heard of Mount St Helens, Yellowstone? there are hundreds of sources of igneous rock in the USA. Go to the USGS site and see what they have on the subject, their publications are available for free download.
No. Lahars are the result of extrusive activity.
Igneous fossils do not exist. Igneous is used to describe something that is formed by fire, magma, or volcanic activity.
Igneous rock is formed through the rock cycle. The igneous rock is formed by magma and lava,then it goes through volcanic activity.
Volcanic activity produces extrusive igneous rock.
Underground
Volcanic activity produces extrusive igneous rock.
These are all formed by volcanic activity. Igneous
igneous rocks
It starts with molten material [magma], when volcanic activity starts the molten material turns into igneous rock.
Intrusive activity is when magma in the mantle or crust starts to cool and crystallize. Igneous rock forms from the crystallization.