Taconic and Acadian Orogeny

 

These are the key events that play the role in what is now Central Park, Manhattan.


Laurentia, ( north american Craton ) is on it's way to a chain of volcanic islands. This is Cambrian Time. In an ever shifting scuffle, NA has rotated about 90 deg. on its axis to its present position.

The subducting NA plate, in Ordovician time collides with the island arc to form the Taconic Orogeny. Several thrust sheets are shoved westward. Cameron's Line Thrust system is created, and now Central Park, Manhattan is under at least 30 kilometers of mountain. But its not over yet, look to the south, Avalonia, another volcanic arc, is also on its way.


Avalonia, In the Silurian is colliding with Laurentia. This induces the Acadian Orogeny. Also, A super continent known as Laurussia is being assembled to the North East, as what is now Europe collides as well, making the Caledonian orogeny.



The acadian orogeny, in the Devonian time is created, and central Park, Manhattan, is deformed again.


Cameron's Line

     To the left the map depicts an approximation of the location for the suture of the Taconic Island Arc and what was Laurentia in the Ordovician time. This is where oceanic crust was being subducted prior to the collision of the arc, and the ancient America, until such time that the two masses collided and regionally metamorphosed much of the East Coast. The depth at which the rocks along the line converged was so deep and hot that they had the consistency of taffy and the lands welded together.

    Another parallel, ductile fault zone named, St Nicolas thrust, is believed to be an older fault system in the metropolitan area, and can be seen in parts of the Bronx separating rock units of schist, gneiss, and marble. Cameron's Line and St. Nicolas Thrust can both be seen in structural interpretations of Central Park as well.