A Summary of Progress in Petrography. in 1887-1896 |
From inside the book
Results 1-5 of 9
Page 9
... phenocrysts of hornblende , and diabases . The former contain oligoclase , and the latter bytodnite or anorthite ... phenocrysts , while the second and third groups contain many porphyritic crystals of a striated feldspar in a ...
... phenocrysts of hornblende , and diabases . The former contain oligoclase , and the latter bytodnite or anorthite ... phenocrysts , while the second and third groups contain many porphyritic crystals of a striated feldspar in a ...
Page 7
... phenocrysts arranged in fluidal lines . In the second case , the exterior modification is a fine - grained panidio- morphic aplite . Since the aplite and the porphyry both contain their constituents in idiomorphic grains , the author ...
... phenocrysts arranged in fluidal lines . In the second case , the exterior modification is a fine - grained panidio- morphic aplite . Since the aplite and the porphyry both contain their constituents in idiomorphic grains , the author ...
Page 8
... phenocrysts of hornblende , and diabases . The former contain oligoclase , and the latter bytodnite or anorthite ... phenocrysts , while the second and third groups contain many porphyritic crystals of a striated feldspar in a ...
... phenocrysts of hornblende , and diabases . The former contain oligoclase , and the latter bytodnite or anorthite ... phenocrysts , while the second and third groups contain many porphyritic crystals of a striated feldspar in a ...
Page 4
... phenocrysts are anorthite and the microlites labradorite . The augite is usually in two generations , the larger crystals being violet in color , while the smaller ones are green . In some cases the porphyritic augites are made up of an ...
... phenocrysts are anorthite and the microlites labradorite . The augite is usually in two generations , the larger crystals being violet in color , while the smaller ones are green . In some cases the porphyritic augites are made up of an ...
Page 5
... phenocrysts of augite and olivine in a ground - mass of plagio- clase , augite , magnetite , and a few flakes of biotite . Sandberger 9 mentions cordierite occurring as an inclusion in the basalt of the Calvarienberg , near Fulda , in ...
... phenocrysts of augite and olivine in a ground - mass of plagio- clase , augite , magnetite , and a few flakes of biotite . Sandberger 9 mentions cordierite occurring as an inclusion in the basalt of the Calvarienberg , near Fulda , in ...
Other editions - View all
Common terms and phrases
acute bisectrix Al,O Amer AMERICAN NATURALIST amphibole analysis andesites apatite augite axial ratio basalt biotite bisectrix brown Bull calcite Colby University color colorless composition containing cordierite corresponding described diabase diorites double refraction dykes Edited by Dr epidote eruptive Fe,O feldspar FeO CaO MgO FeO MnO Förh formula gabbro garnet Geol gneiss grains granite green ground-mass H₂O hardness hexagonal hornblende inclusions isomorphous Jour Kryst Lacroix lamellæ lithophysæ lustre magma magnetite MAKERS SYRACUSE manganese mica microlites mineral occurs MINERALOGY AND PETROGRAPHY.¹ molecule monoclinic Na,O Na₂O nepheline Neues Jahrb olivine optical angle optical axes original orthoclase orthorhombic Petrog PETROGRAPHY.¹ Petrographical phenocrysts plagioclase pleochroic porphyritic porphyritic crystals pressure prismatic produced pyroxene quartz regarded resembles rhombohedral rocks scapolite schists silica small crystals specific gravity spherulites structure substance symmetry thin section tion twinning plane variety W. S. Bayley Waterville yellow yielded Zeits
Popular passages
Page 5 - The olivine is surrounded by a reactionary rim consisting of an inner zone of hypersthene and an outer one of actinolite.