Archive - The Geologic Column

T is for Tektites

They are not meteorites

1 hr ago •

Richard I Gibson

Inverted topography

A former valley

Jun 18 •

Richard I Gibson

Pursuit of identification

Sometimes you lose, sometimes you win

Jun 16 •

Richard I Gibson

Winchell’s Notebooks

Underground mapping at Butte

Jun 13 •

Richard I Gibson

Mine is not from Danbury

Jun 11 •

Richard I Gibson

North Doherty Intrusive Complex

Ultramafic-Felsic-Mafic

Jun 9 •

Richard I Gibson

Silverton Quadrangle

Jun 6 •

Richard I Gibson

Dunbarton Graben

Beneath a nuclear facility

Jun 4 •

Richard I Gibson

Bald Mountain Skarn

Diopside twins and more

Jun 2 •

Richard I Gibson

May 2025

S is for Stigmaria

From the Carboniferous

May 30 •

Richard I Gibson

The Chinle Formation

And bands of rust

May 28 •

Richard I Gibson

Oklahoma’s oil boom

May 26 •

Richard I Gibson

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