fi40 THE GEOLOGY OP MINNESOTA. 



[Granite. 



No. 1044. GRANITE. 



Southeast shore of the little gulf at the southeast side of Kekequabic lake; sec. 11, T. G4-7. 

 Kef. Annual Report, xv, pages 361, 395; Annual Report, xvii, pages 196, 205. 



Mry. Apparently a massive granitic rock, with visible feldspars larger, almost 

 porphyritic, in a fine matrix. 



Mic. The feldspars are conspicuous, but they are in various parts mechanically 

 sometimes out of orientation, so that extinction comes over them by patches. At 

 the same time the margins are somewhat extended by later hooked small increments 

 into the surrounding matrix. Occasionally, but rarely, while the original outline of 

 the feldspar is distinctly set off from the matrix by a marginal increase of impurities, 

 there is a sympathetic partial darkening in a small portion of the adjoining matrix, 

 indicating the continuation of the feldspar growth into the surrounding materials 

 by little hooked tongues. Very frequently, also, the large feldspars embrace numer- 

 ous new growths of feldspars, these lying in independent orientations, each of all 

 the others. They are few and scattered, or they are numerous and crowded. In one 

 instance they occupy the central area of a large crystal, about one-half of the whole, 

 the old crystal being intact only in a marginal band which still exactly outlines the 

 original shape. The appearance of this central area is much like that of the surround- 

 ing matrix, but is less sprinkled with mica needles. For the most part these large 

 crystals appear to be simple Carlsbad twins, but are sometimes nearly lost by the 

 secondary micro-granulation. 



The matrix is made up of fine secondary feldspars, of qii/ni,:, imtxroritc. culcifc, 

 iiKif/netitc, with a sprinkling of green due to shreds of itdinolite and of chlorite, and a 

 few grains of sphene, the whole of it, except the last, of secondary generation, quartz 

 being the latest. One section. 



Age. Archean. 



Remark. This rock appears in the midst of a lot of green schists, referable to 

 the rock No. 1043, to which its relation is not definitely known. It appears to be a 

 regenerated condition of granitic debris. The feldspars resemble those of the por- 

 phyry on the north side of Kekequabic lake. N. H. w. 



No. 1045. GRANITE. 



South shore of Kekequabic lake, near the meander corner of section line between sees. 2 and 3, T. 64-7. 

 Ref. Annual Report, xv, pages 361, 395. 



Mr;/. Thin-bedded, or gneissic, similar to No. 1044, but weathering red. 



Mic. While this rock is similar, in general, to the last, ihefclt/x/Htr is stained 

 with hematite, and appears not to be twinned, and the hornblendic ingredient is 

 almost entirely wanting. The coarser grains make up a larger portion relative to 

 the fine matrix. One (thick) section. 



AJJI-. Archean. N. H. w. 



