Advertisement

You are browsing the archive for limestone Archives - Mountain Beltway.

9 June 2018

Friday fold: contorted carbonates of the Conestoga Formation

Today, in Millersville, Pennsylvania, on the campus on Millersville University, I saw these contorted carbonates. They are of the Cambrian Conestoga Formation, and I saw them on a NAGT Eastern Section field trip led by Lynn Marquez of Millersville University. This deformation is purported to be Taconian, but it looks very much like Alleghanian deformation in similar aged and composition rocks in Virginia. Interesting!

Read More >>

1 Comment/Trackback >>


18 April 2018

Visiting St. Francis’s lovely limestone

The Cretaceous-Paleogene limestone called Scaglia Rossa was used to construct a basilica in tribute to St. Francis. Let’s head to Assisi and take a look.

Read More >>

1 Comment/Trackback >>


10 April 2018

An outcrop showcasing a strand of the Kentucky River Fault System

Roadcuts in Kentucky show Ordovician limestones of two distinct types, replete with fossils and primary sedimentary structures, and juxtaposed by a fault, one strand in the Kentucky River Fault System.

Read More >>

No Comments/Trackbacks >>


9 April 2018

Orthocone nautiloids of the Lexington Limestone

I took a trip last week to Kentucky. My colleague Kent Ratajeski from the University of Kentucky took me out on a nice all-day field trip to examine some of the local geology. I was particularly impressed with the large straight nautiloid fossils that abounded in the Ordovician-aged Lexington Limestone. Here are a series of photos I took of these orthocones, all on pavement exposures (horizontal bedding planes) with my …

Read More >>

No Comments/Trackbacks >>


6 April 2018

Friday fold: “wrecumbent in Wrangellia”

Darrel Cowan of the University of Washington has pitched in a Friday fold. Check this lovely scene out: Darrel says this is a recumbent fold in the Upper Triassic Nizina and Chitistone limestones. I took the photo when I worked for Shell in 1973 or 1974. I’m pretty sure it is on the west wall of the canyon occupied by the Root Glacier, several kilometers NW of McCarthy, Alaska. The …

Read More >>

No Comments/Trackbacks >>


1 March 2018

A GIGAmacro view of a cool outcrop in Scotland

As noted previously, the old way of viewing gigapixel imagery is no more. But there is a new, better way. The GIGAmacro company has a better viewing platform that can be used either with images uploaded to their server or  with pre-existing images that currently “live” at GigaPan.com. Here’s an example: a roadcut of limestone of the Grudaidh Formation (Durness Group) in the Northwest Highlands of Scotland, near Ardvreck Castle, …

Read More >>

2 Comments/Trackbacks >>


13 February 2018

S-C fabric in limestone, Camerino, Italy

Some scaly Italian limestone shows off two foliations (S and C) which reveal the kinematic motions that built the Apennines.

Read More >>

No Comments/Trackbacks >>


26 January 2018

Friday fold: eastern Andes

This image graces the cover of the new report, Challenges and opportunities for research in tectonics: Understanding deformation and the processes that link Earth systems, from geologic time to human time. A community vision document submitted to the U.S. National Science Foundation: Make it bigger by clicking it The photo is of a landscape in the Eastern Cordillera of the Andes, southern Peru, showing folded Permian carbonates cut by a …

Read More >>

No Comments/Trackbacks >>


27 November 2017

Visiting the K/Pg boundary at Bottaccione Gorge, near Gubbio, Italy

A trip to one of the most famous outcrops in the world, a place with a stratum that marked a profound shift in the state of the planet, and a profound shift in geologic thinking. Plus, for the author, it’s a romantic journey back in time.

Read More >>

11 Comments/Trackbacks >>


14 July 2017

Friday fold: chevrons in the Scaglia Rossa, Apennines

The Friday fold visits the Apennine Range of central Italy.

Read More >>

No Comments/Trackbacks >>