The Packsaddle Domain consists of 1274 - 1238 Ma supracrustal and intrusive rocks interpreted as a fore arc basin adjacent to Laurentia. See Mosher (1998).

Lithologies include hornblende, graphite, biotite, muscovite and actinolite schists, marbles, calc silicate rocks, quartzites and quartzofeldspathic rocks interpreted to have been shallow shelf/slope sediments with intermittent mafic and felsic volcanic flows, tuffs, and volcanoclastic deposits.  Some granitic sills intrude the sequence prior to deformation. 

Ages and relationships to VSD & CCD in eastern uplift

Volcanic and volcanoclastic rocks (above) are common within the Packsaddle Domain (see Reese et al., 2000).  Preservation of original textures varies.  The quartz-mica schist below shows a dominant S2 foliation cut by a later foliation parallel to the pen, whereas elsewhere relict sedimentary features (below) can still be identified despite the degree of metamorphism and deformation.  Near the PSD/VSD boundary, metasedimentary rocks such as the tidal flat deposits shown below (two photographs with crossbeds) indicate shallow water deposition near the continental margin. See Mosher (1998).

Igneous rocks (above) also include granitic sills (left), probable mafic flows (right) and minor mafic dikes (upper right) that record all phases of deformation.  Granitic sills are similar in age and composition to intrusive rocks in the VSD, suggesting the two domains were proximal.  See Mosher (1998).