Banded Iron Formation (BIF)

I was recently reminded of how beautiful Banded Iron Formations (BIFs) are and so thought I'd write about them today. The photo on the left is of the BIF that I have displayed on my mantle and specifically is known as a Tiger-eye BIF. It makes lovely jewelery as well as display pieces.

One thing about BIFs is that it is very old. They are some of the oldest sedimentary rocks known and date to as old as 3 billion years old. Earth's conditions were very unique back then and it has not been the same since so the rock is really unusual. BIFs are thought to have formed from the oxygen that was released from ancient photosynthetic bacteria (bluegreen algae) combining with dissolved iron in the Earth's oceans and precipitating out onto the muddy ocean floor. Since this was a seasonal process, you got alternating bands of iron oxide and shale rock. You can also get bands of jasper or tiger eye (a type of quartz). In massive form, BIF is unremarkable except that it is extremely heavy because of the iron content. When polished, BIF can be very beautiful. The red jasper or tiger eye looks great layered with the silvery hematite or magnetite.

Ghost Ranch Camping, Abiquiu, NM

I got to spend some time over the Memorial Day weekend in another beautiful part of northern New Mexico: Ghost Ranch, a "dude ranch" from the 1920's to 1930's, now privately owned. Ghost Ranch is located along US Highway 84, about 65 miles northwest of Santa Fe. There are a couple of "claims to fame" at Ghost Ranch. First, the famous artist Georgia O'Keeffe lived at the ranch in 1934 and painted gorgeous works of art of the area (painting, left). Second, the New Mexico state fossil, Coelophysis, a small Triassic (220 MYA) dinosaur, was found in a quarry there in 1947. The neat thing about the dinosaur find was that there were many skeletons arranged in the rock at once, all jumbled together. Paleontologists concluded that they all died during a flash flood when caught off guard and were deposited in a mass together where they were buried quickly and later fossilized.

I had to do a little research to find out why the Ranch was called "Ghost Ranch" and found my answer in a visitor's brochure at the museum on site (The Ruth Hall Museum of Paleontology and Anthropology). The early New Mexican people called the place Rancho do los Brujos, which means "Ranch of the Witches." There are stories of six-foot tall "earth babies" covered in red hair that howled in the night, and a ghost cow with wings. The old-timers tell stories of canyons filled with the ghosts of men killed in battles between sheep ranchers and cattle ranchers, and by rustlers who once lived in Ghost House on the ranch. I think they just heard coyotes or the wind howling in the night!

We camped in the little campground there with five other families for two nights and had so much fun. The red dirt got everywhere but luckily bleach washed it out of the socks. The red dirt is sediment from the Triassic Chinle Formation consisting of a red siltstone and mudstone mixed with a white- to tan-colored sandstone. (The red Chinle Formation is found also at the Painted Desert in Arizona.) The Chinle Formation is a river deposit formed during a semi-arid climate. (This is the formation that Coelophysis was found in.) Lying on top of the Chinle is the Jurassic Entrada Sandstone, a red, white, and yellow banded mass that was formed from a huge dune field. The banding is caused by chemical reactions with iron inside the sandstone.

We were able to view the cliffs formed by the Chinle and Entrada Formations along a trail to the Box Canyon. It was a 4-mile hike round trip and led along a small canyon with a little creek flowing through. It was truly beautiful at the end of the trail where you find yourself enclosed on three sides by sheer rock walls. Near the beginning of the Box Canyon trail we passed Kitchen Mesa (photo, below left), named either because the trailhead started behind the Dining Hall or because there was a rock "chimney" that you had to climb through to get to the top. I want to take this more strenuous trail when the boys are older. I hear the views from the top are incredible.

The only downsides of the campground are that they don't allow dogs so we had to leave ours with the pet sitter, juniper shrubs as the only shade (ah-choo!), and the horrible biting ants. Oh, and that red dirt that got everywhere! So keep that in mind if you ever want to camp there. But overall, it was a wonderful getaway for the weekend.