In the friday, Oct. 6 news conference on the MER rovers, there was mentioned a linear feature in Victoria crater that may be a dike.
It's mentioned about 10 1/2 minutes into the briefing during a simulated fly-over of the rim of the crater.

Mars Rover News Briefing.
http://www.space-multimedia.nl.eu.or...k=view&id=1055

Here's an image of it posted to the Unmannedspaceflight.com board:

http://www.unmannedspaceflight.com/i...e=post&id=7998

A dike is a solidified portion of lava that protrudes into softer rock. It becomes visible when the softer rock erodes away. There are many examples of dikes in Crater Lake, as with other collapsed volcanic craters.

Phanton Ship dike in Crater Lake.
http://www.billgass.com/Crater%20Lak...s/image004.jpg
Crater Lake.
http://www.billgass.com/Crater%20Lake.htm


Crater Lake and Phantom Ship; Crater Lake National Park, Oregon.
http://www.viewfindersnw.com/photos/pnbf102.jpg
http://www.viewfindersnw.com/?image=pnbf102


If this feature, is a dike that would support the idea that Victoria crater is a collapsed volcanic crater.


Bob Clark