The acoustopolarigrams for sample ODB2297_85 of biotite schist
are similar to the diagrams for schists from the upper section down to a depth of 1101.
The rocks of the Karakoram block are mainly composed of meta-sediments and consist of garnet-muscovite-schist biotite schist
graphitic-schist staurolite-schist calc- schist quratz-schist chlorite-schist and conglomerate with para-gneisses.
chlorite biotite schist
, clinozoisite feldspar rock fragment, altered feldspar-titanite-biotite replaced amphibole-clinozoisite rock fragment, amphibole-rich rock fragments, and garnet-banded biotite quartz rock fragment.
This rock unit contains appreciable amounts of biotite schist
, migmatite, aplite, and quartz-orthoclase-muscovite-bearing pegmatite subordinate in volume to the granite gneisses.
The biotite sometimes forms euhedral crystals and rosettes up to 5 cm across in the country rock and in veins in biotite schist
They are part of a late Proterozoid metasedimentary sequence with underlying paragneisses and overlying biotite schists
intercalated in feldspathized (K-feldspar porphyroblasts) paragneisses.
The quartz augen schist and andalusite biotite schists
are generally stronger, but uniaxial compressive strengths are still low, ranging from 10.
The TM60 was first tested at Birchtree in 1991/1992 when it successfully cut peridotites, nickel sulphide ore and biotite schists
, with some quartzite stringers, up to unconsolidated strengths (UCSs) of around 210 MPa.