After our mind-boggling encounter with the limestone strata turned lurid pink by their high-pressure encounter with subduction, our band of merry geologists set off for a stroll: We began the walk in greenschist + blueschist mélange, as seen here with a Turkish 1-lira coin (26 mm diameter; about the same size as a U.S. quarter) … Read more
Picking up where we left off… I was telling you about the field trip I took through Turkey’s Tavşanlı Zone, a tectonic suture zone between fragments of continental crust that accreted during the closure of the Tethys Ocean. Day 2 of the trip dawned and we broke fast, and then headed out to a bizarre … Read more
In honor of this month’s Accretionary Wedge (geoblog carnival; this month the theme is “deskcrops”), I recorded the following short video, showcasing some samples I have in my office: stromatolite (western Montana), conglomerate (Patagonia), schist (New Hampshire), anorthosite (New York), amygdular meta-basalt (Virginia), amphibolite (California), hematite concretions (eastern Montana), and a stretched-pebble lineated meta-conglomerate (Turkey).
Picking up where we left off last time, we were in some partly-serpentenized peridotite, part of the Burham Ophiolite in Turkey’s Tavşanlı Zone, an ancient tectonic suture. Our next stop on the field trip allowed us to visit some diabase dikes: Here’s a close-up of the right contact of the dike with the host peridotite: … Read more
Yesterday, I shared a few thoughts about the first couple of stops on the field trip I took earlier this month from Istanbul to Ankara, prior to the Tectonic Crossroads conference. Today, we’ll pick up with some images and descriptions from the next few stops. After lunch, our next stop brought us to a relatively … Read more
Before the Tectonic Crossroads conference two weeks ago, I had the good fortune to participate in a Istanbul-to-Ankara geology field examining the Tavşanlı Zone, a tectonic suture zone where a portion of the Tethys Ocean basin closed. This paleo-convergent boundary is marked by a suite of interesting rocks, including blueschists, ophiolites, and eclogites. I’d like … Read more
For the second year in a row, more exotic travel plans meant that I wasn’t able to attend the superb Virginia Geological Field Conference. I see that they have now posted some photos on the group’s Facebook page, so go check them out to see what we both missed last weekend. Here’s a taste: Sheared … Read more
Today I’m in the air, on my way back to Turkey for the Tectonic Crossroads conference being held in Ankara next week. Before the meeting, I’m joining a field trip to examine a subduction zone complex. Over three days, we will drive from Istanbul to Ankara by way of ophiolites and blueschists and other geologic … Read more
Over the summer, when my blogging access was limited to my iPhone, I uploaded a photo (taken with the iPhone) of a metamorphosed graded bed on the summit of Mount Washington, New Hampshire. Here’s another one that I saw, further down on the mountain, on the Auto Road (famous for its iconic bumper sticker): Lens … Read more