A couple of months ago I went hunting for xenoliths in the Cieneguilla Basanite, and came across a somewhat puzzling dike in a road cut. So Friday I took time while returning from Albuquerque to visit the area again and take a longer look. First, some background. Don’t worry; the...Read more

The long weekend gave me opportunity for three short wanderlusts, whose common feature was the presence of faulting. Friday I planned to visit a hydrothermal breccia pipe shown on the geologic map at the north end of Aspen Ridge. Aspen Ridge is the easternmost of the north-south ridges that form...Read more

This is a hike I’ve been contemplating for some time. However, I’ve had lots of other interesting things to do, and settled on finally doing this hike this weekend largely because of a combination of favorable weather and a desire to take a new friend and his family on a...Read more

We’re in the midst of the monsoon season, but the monsoon here typically has breaks of a few days of quite dry weather. One such was forecast for this weekend, and naturally I had to take advantage of it. I was torn between a number of options. I would like...Read more

Not too long ago, I visited the San Pedro Mountains, which contain the oldest rocks exposed in the Jemez region. You can visit that post for a more detailed explanation of the geology of this area, but the short version is that the San Pedro mountains are a block of...Read more

This unit has interested me since I first learned about it, and I’ve visited it once before. Basanite is a somewhat rare and unusual igneous rock type, very low in silica and somewhat enriched in alkali metals. The Cieneguilla Basanite is the only basanite identified so far in the Jemez...Read more

For some time, Gary Stradling has wanted to find some good chunks of obsidian on which to practice his knapping skills. (Not to be confused with “napping”, at which we are both already skilled.) Raw obsidian suitable for toolmaking must of course come in chunks large enough to work with,...Read more

320 million years ago, New Mexico was a shallow tropical sea studded with large islands. These were the peaks of the Ancestral Rocky Mountains, formed when Africa collided with North America and compressed the Earth’s crust in the New Mexico area. Blocks of crust were forced upwards by the compression...Read more

My first crack at this trail ended badly when I realized my camera wasn’t focusing properly. Repairs were not entirely successful and I ended up with a new camera. A subsequent attempt ran out of time. This time I had the whole afternoon, a working camera, and flawless weather. But...Read more

I’ve been to the Harding Mine three times before. The first was as a middle-school kid, for a science field trip, which is one of the great happy memories of my childhood. I still have some good specimens from that trip. The second was around nine years ago, with Bruce...Read more