...This folding resulted in faults, metamorphism, and secondary structures of several kinds. There were three periods of folding — one at the close of the Lower Cambrian, affecting the central portion of the basin; another at the close of the Ordovician, more far-reaching...

...1 feet thick. STRUCTURAL GEOLOGY. 8TRUCTURK SECTIONS. Section A, PI. Ill, shows the (inconformable relations between the large synclinal outlier of Hudson...before the Silurian beds, is shown by the well-known uuconformable relations between the Ordovician and the Silurian at a number of points in the Hudson...

...synclinal outlier of Hudson shale and the Lower Cambrian; also that between the Silurian Kensselaer grit and the Lower Cambrian, as well as the overthrust...Cambrian, another at the close of the Ordovician. arid still another which metamorphosed and folded the Silurian bods. That these last two movements...

...later thrown into a series of parallel folds, diminishing in altitude from east to west. There were three periods of folding: one at the close of the lower Cambrian; the second, more extensive, at the close of the Ordovician; and the third either in Devonian or Carboniferous...

...later thrown into a series of parallel folds, diminishing in altitude from east to west. There were three periods of folding: one at the close of the lower Cambrian ; the second, more extensive, at the close of the Ordovician; and the third either in Devonian or Carboniferous...