THE SUDBURY LACCOLITHIC HEET ilgp 
In the above table No. 1 and No. 2 are from the basic edge of the 
southern range near Blezard mine; analyst, Professor T. L. Walker. 
No. 3 is from the basic edge of the northern range near Onaping; 
analyst, Mr. E. G. R. Ardagh. No. 4 is from the Creighton mine 
near the ore body; analyst, Mr. M. T. Culbert. No. 6 is ofa syenitic- 
looking specimen from near the middle of the Onaping section; 
analyst, Mr. Ardagh; and No. 7 is by the same gentleman, of a 
greenish-gray specimen from the acid edge at Onaping. No. 8 is 
from near the acid edge of the Blezard-Whitson lake section; analyst, 
Professor Walker. No. 9 is from the acid edge on the north shore of 
Fairbank Lake in the southern range, the rock being dark green- 
gray and somewhat schistose; analyst, Mr. Ardagh. No. ro is from 
near the acid edge of the Blezard-Whitson lake section; analyst, Mr. 
CIB Hox: 
It should be mentioned that No. 4, from the Creighton mine, is 
exceptional for the basic edge, containing considerable quartz, micro- 
cline, and micropegmatite, perhaps absorbed from the adjoining 
granitoid gneiss. 
The two analyses of specimens taken about half-way between the 
basic and acid sides of the sheet do not differ greatly in composition 
from analyses of rock from the acid edge itself, and must be looked 
on as really belonging to the micropegmatitic side of the eruptive. 
Averaging the first four analyses as representing the norite, and the 
last six as representing the micropegmatite, we get the following 
results: 
Basic Average | Acid Average | Total Average 
SiO saat sel aes acne Meier arate 54-615 66.873 61.970 
INO Rae socenbsomadaa on mabe Soca pour 18.437 12.745 15.022 
TR ORRG a.cinls tren tegoimins Gre piece Ciao OS 590 1.543 Te. 302 
lite O}G aig AEROS Sin oe On eae nin Baan ere ei 8.365 5-502 6.683 
IMO) scadcoodnucnoebobonp anodes daudde 4.510 1.263 2.542 
C2Oecrdnsebonue comer oun ummbon tao mao 6.715 Qqei] 4.322 
INDIA On Sio sanied ep mosice nab eenlo poe ome or 2.267 3.827 3.203 
IO) 35 Gigo oC DA OE ain SO irs 1.417 2.787 2.239 
JELAODE dicot Acros seeate Crete Ber Cae aera nary Oe are T .085 1.188 1.147 
B1bi OMe eta ree eee cnewctirtia hase ethene TUG .502 .763 
IP O)izs oars G6 o:0b:0 OB Oa a AG Eee uiherol Oa EG .202 .182 
AV rat @ ee ey wena cs Cis these eee caatshc os egsra coat tea eee 722 .060 .065 
IMiimorsullos tances cytes act ait eintaerei st sie iets 22 ON miller eigen tis emia deer 
ANGEL egos oogobeoncedunaDooE sob OlNDO 99-752 99-279 99.500 
