Attn Skyline hikers: Tramway is closed

[Florian]

I'm a bit late on this notice but the tramway is closed through Friday, 9/25. If you are planning to hike Skyline you will not be able to get a ride down. You'll have to hike back down Skyline or out to Idyllwild.

-Florian

[Wildhorse]

Just like the good old days before the tram.

[Hikin_Jim]

Just like the good old days before the tram.

All it would take is one good earth quake...

HJ

[Perry]

Maybe. Maybe not. Hard to say whether something or nothing would happen.

http://www.bbc.com/news/science-environment-33772541

http://news.uci.edu/press-releases/prec ... nnections/

[Hikin_Jim]

Interesting -- although I still wouldn't want to be on the tram during a quake.

HJ

[cynthia23]

Wow, those are fascinating articles, Perry. One of those rocks they studied had been sitting in same position for 18,000 years! So perhaps our region is not as at-risk in a major quake as some others. On the other hand, I understand that the Agua Caliente say there was a big earthquake in this region at the end of the 19th century which radically changed the course of the river coming of Tahquitz Canyon.

I guess either way, and like HJ, I prefer not to find out while riding the PS Tram.

[zippetydude]

Interesting post Perry, and what a clever way of determining the severity of ground shaking! All sorts of amazing research is going on right now. A couple years ago I ran into a survey team on top of San G. They had a high tech gadget for GPS up there that was measuring the motion of the peak for several days to get extreme accuracy. They told me that San G is actually not moving north or south, it's on a small fragment that is actually spinning like a ball bearing. Amazing stuff.

As far as the Tram falling, I'd bet it will survive 100% intact. It was engineered to handle lateral motion due to wind and vertical motion due to the tram's weight going over the towers. It is, as far as I know, bolted down into the bedrock. It might shut down due to the motion induced, but I very much doubt it would actually collapse. That being said, I'm with everyone who said they wouldn't want to be on it during a powerful quake. You just never know...

z

[Wildhorse]

It is probably designed to withstand a specific amount of ground acceleration. Designers may have estimated the frequency in years that earthquakes from any fault in the area would cause that level of ground acceleration. For example, it might have been designed for a frequency of one or two hundred years, based on estimates made at the time of construction. Who knows what experts believe today about such things. That kind of guesswork is expensive to purchase. Even if one knows such numbers, one really does not know what may happen to the tram or one's house.