Galadriel is a fictional character from J.R.R. Tolkien's legendarium, specifically from "The Lord of the Rings" series. As a work of fiction, the events and abilities depicted in the story are not subject to scientific analysis or explanation. Therefore, any explanation for Galadriel surviving a pyroclastic flow would be purely speculative and not based on scientific principles.
Pyroclastic flows are extremely hot and fast-moving clouds of volcanic ash, gas, and other volcanic materials. They are highly destructive and can cause severe burns, asphyxiation, and death. In reality, surviving a direct hit from a pyroclastic flow would be nearly impossible for a human or any living creature.
It's important to remember that fantasy literature often includes elements of magic, supernatural powers, and extraordinary events that defy the laws of nature. In the case of Galadriel, her survival from a pyroclastic flow could be attributed to her unique abilities as an elf or the intervention of other magical forces within Tolkien's fictional world. However, without specific details from the story, it is impossible to provide a more detailed explanation.