REPORT OF THE CHIEF ASTRONOMER 



291 



SESSIONAL PAPER No. 25a 



Analysis of basic granodiorite, Bayonne batholith. 



Mol. 



Si0 2 60-27 1-005 



; Ti0 5 -63 -008 



A1 2 3 17-17 -169 



Fe,0 3 ^ 2-36 -015 



Feb 3-67 .051 



MnO -14 -002 



MgO 245 -061 



CaO 6-49 -116; 



SrO.. ..■ -04 



BaO -04 



Na.0 2-92 -047- 



KoO 3-25 -035* 



H.0 at 110°C -15 



H^O above 110°C -23 



P 2 5 .. ". -20 -001i 



100-01 



Sp.^r 2-785 



The calculated norm is : 



Quartz _, 13-32' 



Orthoclase 19-46 



Albite 24-63 



Anorthite 24-19 



Hyper sthene 7'17 



Diopside. 5-90 



Magnetite 3-48 



Ilmenite 1-21 



Apatite -31 



Water -38 



100-05 



The mode (Eosiwal method) is approximately: 



Quartz.. 19-5 



Microperthite 17-4 



Orthoelase 3-7 



Andesine 23-8 



Hornblende 16-2 



Biotite 11-8 



Augite 4*4 



Titanite .6 



Magnetite -9 



Apatite -5 



Epidote and kaolin 1-2 



100-0 



In the Norm classification the rock enters the sodipotassic subrang, har- 

 zose, of the alkalicalcic rang, tonalose, in the dosalane order, austrare. In 

 the older classification the rock must be regarded as a basic granodiorite. It 

 is quite possible that the batholith has more acid phases in the region north of 

 the Boundary belt and thus nearer the centre of the mass. 

 25a— vol. ii— 194 



