Tuesday, December 31, 2013

Another Road Slump on a Scenic Southwest Road - The Tijuana-Ensenada Highway Collapse

Scenic road slump south of Tijuana, Mexico. Photo by David Maung
My friend Don K. of Flagstaff made me aware this morning of a monumental collapse of another southwestern road, this one on an important coastal link between the cities of Tijuana and Ensenada, Baja California, Mexico. Readers of this blog will recall the geologic slump that occurred this year on February 20 along a scenic stretch of highway between Flagstaff and Page, Arizona. There the Chinle Formation gave way necessitating a possible two-year road closure.

This collapse occurred just about 10 days after a 4.6 magnitude earthquake struck the area. You can read the official US Geological Survey earthquake summary here. The quake was about 58 miles southeast of Ensenada and 257 miles air miles from Phoenix. It is unknown at this time if the quake and the slump are related.

The San Diego Union-Tribune newspaper published an article about the slump and road closure and can be read here. Attached to this article is a video survey of the damage which can be viewed here. Be sure to look at the photo gallery embedded within the article - it shows clearly how soft the base material is. Makes one wonder how a road was even possible in the first place on such a road base.

Note the murky water offshore, likely from slump material entering the sea. Photo by David Maung

1 comment:

Dr. Jack Share said...

Just a few observations: Judging from the first photo, the displaced, downslope road appears rotated on an axis parallel to the slope implying a rotational rather than translational slump. On the second photo, the joints on the slope radiate concentrically implying the apex of the slump is directly upslope. Also, the joints perfectly continue downslope across the surface of the road.