The geologic history of Virginia is fascinating. Did you know that a chunk of the African continent once sat atop most of the state? Events before and after that has shaped Virginia's amazing landscapes and resources. Origins can be traced back to an initial super-continent Rodinia some billion years ago, before land creatures. Virginia, nestled in the middle of Rodinia, sported a large sea next to it as Rodinia rifted apart, but unlike today, that sea was to Virginia's west and mountains in its east, the opposite of today! Water drained from those mountains to a primal sea creating huge swampy regions with abundant plant life. Varying sea levels and sediments began burying swampy peat over millions of years laying the foundation of our western Virginia coal reserves of today. But how does the African continent fit in or over?

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Virginia, part of the North American or Laurentia tectonic plate or continent, remained relatively the same after Rodinia had separated, building more dense plant and sediment layers, like a thick cake, for hundreds of million years until the the blockbuster of all continental collisions occurred: the Allegheny Orogeny, some 300 million years ago. It's hard to think of crashing when objects are only moving at inches per year, but like a freight train that can't stop on a dime, the African continent first crunched and then pushed over portions of Virginia. Inspecting the "damage" caused by the continental collision reveals significant changes. It laid the framework for the Virginia we see today.

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In the far western part of the state, the effect of the crash tended to be limited to uplifting, the Appalachian plateau pushed up. But moving eastward, where the crash was a crunch, we find the original bedrock compressed and folded, similar to the folds in a pushed carpet. The layered cake of millions of years became folded and compressed, creating heat and pressure and turning the softer "cake" rock to harder metamorphic rock like shale. That dynamic is the basis for the mountain ridges we see near the Shenandoah Valley, the Blue Ridge even harder rock to its east. Farther east, the continental collision left the edge of Africa atop Virginia, only to be eroded away once that super-continent of Pangea split and the African continent drifted away and created the Atlantic Ocean. The Piedmont and Coastal Plain then followed its own geologic path, relatively flat.

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Today we find 3 distinct coal fields in Virginia: far SW, Valley and Eastern coal fields. The Valley coal fields are most closest to Roanoke, located in Montgomery, Augusta and Rockingham counties (we can point-out this geology on some of our hikes). Valley coal is one of the purest in the state, many impurities were squeezed out by pressures caused by primordial land or "cake" being folded and compressed by the continental collision with Africa. Purer or Anthracite coal is sought for metallurgical purposes such as making steel. Virginia produced roughly 1.3 billion dollars of coal in 2021, though most being bituminous coal used for energy production. Coal, a natural resource derived from plants, is an integral element in our amazing Appalachian chain.