Saturday, May 24, 2014

Beautiful Montana!

On my way to some Geological Society of America Meetings in Bozeman, Montana last week, I took the drive from Dillon to Twin Bridges to Whitehall to Bozeman on the way there. And on the way back I drove the road from Bozeman to Norris to Ennis to Virginia City and then back to Twin Bridges. The scenery was spectacular. I can see why the people of Montana love their state. The map below is courtesy of Arrow Real Estate, Ennis, Montana.

Our trip in Montana began along I-15 as we stopped at the rest stop near Lima. The sky was clouding over but I took this shot of the Lima Peaks.

I wondered what the Lima Peaks might look like on a nice sunny day with just a few clouds, so I Photoshopped the sky into this picture. You can see what the sky really looked like in the photo above.

After stopping in Twin Bridges to drop my wife off at her brother's ranch, I headed north toward I-90 and the town of Whitehall. Thunderclouds were gathering, but the sun was leaking through as I passed this scenic spot.

After the meetings in Bozeman, I drove west along Highway 84 towards Norris. The ranches were beautiful, particularly this one with the Spanish Peaks covered in snow as a backdrop.

Even the barbed wire seemed to need a photo.

A bit farther along Highway 84 near the western edge of Gallatin Valley. The farms and mountains were incredibly beautiful.

In Bozeman Pass, I stopped to look at the rocks. I am a geologists, after all. These Precambrian biotite schists were folded and faulted into this interesting pattern.

Coming down out of the pass, I found the Madison Valley to be equally lovely. The Madison Range is the backdrop on east side of the valley.

 On the west side of the valley, the ranches sit at the foot of the Tobacco Root Mountains.

Looking down from Highway 287 towards Ennis in the valley and the Madison Range in the back.

Another view back across the Madison Valley, with Sphinx Mountain in about the center of the photo.

A close up of Sphinx Mountain taken with my zoom lens. I can see why it was called Sphinx Mountain.

Another ranch situated at the foot of the Tobacco Root Mountains near Alder.

A close-up of the Tobacco Root Mountains in the view above.

Thursday, May 22, 2014

Birds at Clark Ranch, near Twin Bridges, Montana

During a short stay at my brother-in-law's ranch this past week near Twin Bridges, Montana, I took a few photos of some of the birds that frequent their front porch and yard. I could have spent a couple more days just watching these colorful birds.

 Male Bullock's Oriole coming to the feeder for grape jelly and oranges.

 Male Mountain Bluebird standing guard at the house.

 Female Cassin's Finch with the typical pronounced crest.

 American Goldfinch wondering when it will be safe to return to the feeder.

 House Finch enjoying a breakfast of sunflower seeds.

A Grackle trying to get his turn at the birdfeeder.

 Another Bullock's Oriole.

 A female Western Tananger enjoying the orange and jelly.

 Male Western Tananger.

Male and female tanangers at the feeder.

You can read more and see more pictures of these birds at:

Tuesday, May 13, 2014

Some Features on the Nugget/Navajo Sandstone, San Rafael Swell, Utah

A dinosaur track in the top of the Jurassic Nugget Sandstone (also called the Navajo Sandstone) on the San Rafael Swell, Utah. This was located in the bottom of a wash and has since been covered or eroded away. The middle toe must have been loaded with mud as the dinosaur stepped into this spot.

An interesting structure on the same surface as the dino print above. I thought this might be a burrow of some type, but my friend and colleague, Dr. Steven Hasiotis, who is an expert in trace fossils was unconvinced. We decided it must be some kind of fluid "pebble dike" like structure, where the solid sandstone was broken up and then redeposited as water or other fluids moved through the rock.

Also found on the Nugget Sandstone on the San Rafael Swell, this picture shows the individual avalanche deposits of sand that tumbled down the dune face before this became a rock.

Here is another view of this dune in the Nugget Sandstone. You can see the surface with the avalanche deposits in the foreground and in the background a lower face of the dune that is covered with ripples.

In one spot on this petrified dune, there were these small circle-like structures (see piece of chalk for scale). I am not sure what caused them.

Just below the dunes shown above, the sandstone is ribbed with giant polygonal cracks filled with sandstone that is slightly more resistant to erosion. My colleague, Ron Blakey at Univ. of Northern Arizona has published several papers on these structures.

One of the most interesting features to me found on a couple of the dune faces were these  triangular and rectangular structures. They represent salt or gypsum that crystallized in the sand and, after leaving an impression, dissolved away.

Another probable dinosaur undertrack on the top of the Nugget.

Along the edge of the wash, a series of these possible dino tracks seem to form a trackway.