. The Quarterly journal of the Geological Society of London. SCHIST- / GRITS Dubh ,/.i,r AND MICA-SCHIST^./ WITHGRIT-BANDS,,-- S LATES. a Thetrict [The asterisks indicate localities where speci-mens of the rocks described in this paperwere obtained.] YIII. Contact-Metamokphism. One other phase of metamorphism in the district must be recordedbriefly, and that is contact-metamorphism. In the albite-gneissarea are numerous intrusions of what are called the newer granitesand diorites ; that is to say, a series of intrusions well-knownin the Highlands, and probably in the main of Old-Ked-Sandstonea
. The Quarterly journal of the Geological Society of London. SCHIST- / GRITS Dubh ,/.i,r AND MICA-SCHIST^./ WITHGRIT-BANDS,,-- S LATES. a Thetrict [The asterisks indicate localities where speci-mens of the rocks described in this paperwere obtained.] YIII. Contact-Metamokphism. One other phase of metamorphism in the district must be recordedbriefly, and that is contact-metamorphism. In the albite-gneissarea are numerous intrusions of what are called the newer granitesand diorites ; that is to say, a series of intrusions well-knownin the Highlands, and probably in the main of Old-Ked-Sandstoneage, which have been intruded after the regional effect of these intrusions on the albite-gneisses is approaching such an intrusion as the Beinn-Yane (Mheadhoin)diorite or the Inversnaid hyperite, the albites are seen to assume ared coloration, due to the oxidation of the magnetite-inclusions, while 26 MR. E. H. CUNNIS6HAM-CRAIG ON [Feb. I904, chlorite begins to give place to biotite. Under the microscope thealbite soon appears cloudy and decomposed, and tin ally, as the junc-tion is approached, vani
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Keywords: ., bookcentury1800, bookdecade1840, booksubjectgeology, bookyear1845
