Geochemistry of the Namurian Lismore Formation, northern mainland Nova Scotia; sedimentation and tectonic activity along the southern flank of the Maritimes Basin

Chemical analyses for major, trace and REE, and Sm-Nd and Rb-Sr isotopic analyses are presented for clastic rocks in an upwards-coarsening 2500 m thick fluvial sequence deposited along the S flank of the Maritimes basin of Atlantic Canada. The geochemical data can be subdivided into two groupings that primarily reflect varying contributions from accessory phases, clay minerals, or rock fragments. The lower group shows an important contribution from underlying Silurian rocks, with a relatively minor input from late Devonian granitic rocks of the adjacent Cobequid Highlands and possibly metasedimentary rocks from the Meguma terrain to the S. The data from the upper group reveal a more important contribution from the granitic rocks of the Cobequid Highlands. This variation is considered to constrain the age of renewed motion and uplift along the faults on the S flank of the Maritimes basin.