San Ysidro Anticline

Our winter adventuring has recently taken us to local, nearby areas.  A popular site is the San Ysidro Anticline of the Ojito Wilderness near the small village of San Ysidro.  Folks come here for biking and hiking.  The north end of the Anticline gets somewhat less attention, however, but holds some of the most interesting treasures, and that’s where we adventured.

 

To capitalize on the continued February warm trend, we decided to revisit the Ojito Wilderness, one of our favorite nearby places in New Mexico.  One section of the Wilderness includes the San Ysidro Anticline.  This is a long uplift that has been eroded away through the middle exposing a lot of Jurassic and Cretaceous deposits.  Dinosaur bones, gastroliths (dinosaur crop stones) and other fossils can be found in the area.  One of the largest dinosaur skeletons ever discovered, of a Seismosaurus, was found nearby.

 

 

 

Areas near the north end of the Anticline have deep gypsum formations, portions of which are mined to develop drywall for building homes in Albuquerque.  In other areas calcium carbonate is leached out from underground by springs that develop fascinating travertine domes with unusual textures as the minerals precipitate out.  Many of these domes are formed along the hillsides, and some of them have collapsed making deep pockets.  One small spring was bubbling with gasses released from underground.  The most impressive of the travertine formations is the Devil’s Hole, a deep collapsed dome that we found to have algae-rich water in the bottom.  Super cool.

 

 

In the distance we could see many amazing features including the Sandias, Prieta Mesa, Cabezon and the Jemez Valley, many of our favorite areas to explore.  After leaving the Devil’s Hole, we wandered down through a Gypsum Gorge with incredible canyon walls.  There were small ice-flows in the bottom and a trickling, muddy stream, also with winter algae.

 

 

Around the corner from the Gypsum Gorge is a Gypsum Slot Canyon that we have visited once before.  It’s the only slot canyon we know of made of gypsum.  We attempted to approach the slot from the bottom, but the arroyo below it was shockingly choked with dense piles of tumbleweeds.  The carcasses of these evil plants were 10-15 feet deep in places.  We were able to get around them for the most part, but then one place required us to scale the dirt sides of the arroyo, and as I tried to move along the sides, I fell in!  I’m pretty allergic to these things, and as I was stabbed by the stupid little barbs on these heinous fiends I started to swell up in a rash.  I had to clamber out of the arroyo, with Riki’s help, and we scaled the side of the arroyo and out.  We gave up at that point.  I hope some major rains flood the bottom of these arroyos so we can be rid of the tumbleweeds!

 

Even with the challenges of the vile weeds, we had a lovely and wonderful day exploring a favorite nearby site.