Another new insight from last week’s visit to the Outdoor Lab was that they have several fine examples of native copper found in float of the Catoctin Formation on their property. Here are a few examples: Classic examples – a bit of malachite in there too, it looks like. I wasn’t totally shocked when I … Read more
A guest “Friday fold” from South Africa: folded gneisses, flavored with other treats of a geological nature.
I’ve mentioned this phenomenon before, but I thought this was a particularly impressive example, found in my back yard over the weekend. Pipkrakes (ice “fibers”) with iron oxides and oak leaves, Fort Valley, Virginia, January 2013. Dana saw some in Seattle, too.
Callan continues his week-long recounting of his five-day backpacking trip from the Cape of Good Hope to Cape Town, South Africa, along the Hoerikwaggo Trail. Today, we examine the jointing, oxidizing and reducing fluid flow, and the emplacement of ore veins.
Today, I’ve got a batch of additional photos of the Walker Top Granite to share, variably mylonitized (sheared out under ductile conditions)… Nice garnets in some spots: Delta porphyroclast: Lovely sheared-out rocks…
My students Chris Johnson and Robin Rohrback have been busy adding to the Mid-Atlantic Geo-Image Collection. Check out a few of these new GigaPan images: [gigapan id=”117788″] link [gigapan id=”117786″] link [gigapan id=”117390″] link [gigapan id=”117346″] link [gigapan id=”116919″] link
The Friday fold is seen at one of the stops on Callan’s pre-GSA-Charlotte field trip: a small waterfall in North Carolina’s Inner Piedmont.
Last winter, around 10 months ago, Lily and I were walking along the shore of Hermanus, South Africa, when I saw a little closed-drainage pool in the sandstone, harboring a briny distillation of the South Atlantic Ocean. Neat salt “rim” on the edge of the pool… Also note the ~cubic crystals at the bottom of … Read more
After our “pre-honeymoon” sojourn to the Canadian Rockies last summer, Lily and I returned to the U.S. via Porthill, and then drove over to a place I’ve been wanting to visit for a long time: Yaak, Montana. Yaak (or “the Yaak“) is way up in the Kootenai National Forest, in way-way-way-northwesternmost Montana. We camped out … Read more
Callan shares some photos of “leopard rock” (porphyritic mafic dikes) seen along the Beartooth Highway, northeast of Yellowstone National Park.