ANORTHOSITE-GABBRO IN NORTHERN NEW YORK 37 
differentiation into such layers, probably accompanied by differen- 
tial movements, during the intrusion, or of local intrusions of 
heterogeneous portions of the magma in which the differentiation 
took place before intrusion along local zones. 
7. Certain local dikelike facies extra rich in ferromagnesian 
minerals, which are not sharply separated from the main mass of 
the anorthosite-gabbro and send dikelets into it, are basic differen- 
tiates from a lower level forced upward into the more normal 
mass which had already more nearly approached final consolidation. 
8. The granulation of the feldspars in those portions of the 
foliated lighter-gray gabbro and anorthosite-gabbro in which the 
ferromagnesian minerals show little or no granulation is believed 
to have resulted mainly from movements in the magma before 
final consolidation, that is during or after the crystallization of 
the feldspars, but while the ferromagnesian minerals were still 
more or less liquid. In other words, we are here dealing with a 
protoclastic texture. Such pressure could not have been applied 
after complete consolidation of the magma because, if so, the 
dark minerals would also be granulated. Where the ferromagnesian 
minerals also show granulation, this probably resulted from mag- 
matic movements just prior to final solidification, or from pressure 
upon solidified portions of the mass exerted by locally intruding 
portions of still liquid rock. The possibility is conceded, however, 
of the development of some granulation of this type by exter- 
nal application of moderate pressure upon the whole body of 
anorthosite-gabbro, but the localization of such granulation ren- 
ders such an explanation less likely. 
DARK DIKES RICH IN HORNBLENDE AND SCAPOLITE 
At locality 7 there is a fine display of rather remarkable dikes. 
The country rock is there mainly a medium-grained, dark-gray, 
rather typical, non-foliated gabbro with ophitic texture. No. 51 
of the table gives the mineral content of a thin section. 
Over an area of several acres the rock just described is cut 
most irregularly by a network of numerous dikes of dark-gray, 
highly foliated, fine-grained to medium-grained rocks consisting 
chiefly of scapolite and hornblende together with some quartz and 
