Friday fold: Difficult Run fun
The Friday fold takes us to some high-grade metamorphic rocks in the Piedmont of northern Virginia.
The Friday fold takes us to some high-grade metamorphic rocks in the Piedmont of northern Virginia.
Today’s edition of the Friday fold is a cross-section: Doesn’t look too spectacular, does it? — “Why, it’s just a bunch of strata folded into anticlines and synclines,” I’ll bet you’re thinking. But no… it’s actually more complicated than that. We know it’s more complicated by examining geopetal primary structures in the strata. Geopetal structures … Read more
The Friday fold is a series of strata underwater near California’s famed “Mavericks” surf break.
This week’s edition of the “Friday fold” takes us to Route 55 in West Virginia, to deformed Appalachian strata of the Valley and Ridge province. A few bonus structures are also shown — some ripple marks, slickensides, and pencil cleavage.
Norwegian structural geologist Haaken Fossen contributes two incredible images for this week’s Friday fold: a pavement of drastically-shortened banded iron formation from Minnesota, and a trio of three white granitoid dikes, buckled within a gneiss from the Jotun Nappe, in the Norwegian Caledonides. Gorgeous images of gorgeous folds, with links to the rest of Fossen’s collection.
The weekly example of a fold is especially… “cool” this week.
The Friday fold visits the French Broad Massif of North Carolina’s Blue Ridge province.
Today’s Friday Fold comes to us via Pete Berquist of Thomas Nelson Community College in Hampton, Virginia. Check it out: Pete explains what’s going on here: I cannot provide an exact location but this is within the Mars Hill Terrane (MHT), which is an distinctive swath of Mesoproterzoic basement extending ~50 km x 100 km … Read more
Sometimes you find folds in funny places, like the side of a monastery. Guest fold from Maitri.
For the structural geology fans among AGU’s readership, enjoy the weekly installment of the Friday fold.