Annual report . e is that from the areajust west of Sacandaga Park. A slide shows: 35 per cent ortho-clase; 12 per cent microperthite; 18 per cent oligoclase to andesine;25 per cent quartz; 7 per cent biotite; 2 per cent magnetite; and 1per cent zoisite, zircon, apatite and garnet. Mineralogically thisrock is almost exactly like the more acid syenite except for the sub-stitution of biotite for hornblende. The boundary line between thegranite and syenite here can not be drawn with accuracy because ofthe apparent gradation of the one rock into the other and this fact,together with the failure to
Annual report . e is that from the areajust west of Sacandaga Park. A slide shows: 35 per cent ortho-clase; 12 per cent microperthite; 18 per cent oligoclase to andesine;25 per cent quartz; 7 per cent biotite; 2 per cent magnetite; and 1per cent zoisite, zircon, apatite and garnet. Mineralogically thisrock is almost exactly like the more acid syenite except for the sub-stitution of biotite for hornblende. The boundary line between thegranite and syenite here can not be drawn with accuracy because ofthe apparent gradation of the one rock into the other and this fact,together with the failure to find any evidence of one of these rockscutting the other, leads to the belief that the granite and syenite areof practically the same age and that they are differentiation productsof the same magma. The following analysis of what is regarded as the most typicalgranite (above described), from one and three-fourths miles north-northwest of Northville. has been made for the writer by ProfessorE. W. Morley: Plate 2. W. J. Miller, photo Granite porphyry showing a typical outcrop with its mile southwest of Sacandaga Park. GEOLOGY OF THE BROADALBIN QUADRANGLE Si Al, Fe2 Fe Mg Ca O Na« K2 O H2 O Ti P2 05 Mn Ba O S ........ CI , F Zr O 19 71-45 1383 ?56 •32 .42 • 03•17 • 02 • 0203 • 01 • 02 The norm and place of this rock in the quantitative chemicalclassification are calculated as follows: Si O. .:2 M2n°6;.: S CI F . Percent 71-45 • 561 44^ 2. 6 3 •03f • • L .44* ?.62f ).og|• 32f Mol. Ilm. • . Apat. Orth. 39065 Alb. An. 252 50 42 I 25 1Orth. Cor. Mag. Hyp. Qtz. 468 , = 93-49 Cor. 3i J 93-49 Order, Fem. Q Hyp. .76Apat. 06 J99-57 Rang, F
Size: 1409px × 1773px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectscience, bookyear1902
