336 R. A. DALY THE OKANAGAN COMPOSITE BATHOLITH 



irregular block of roof rock almost completely surrounded and probably 

 underlain bj r the Similkameen granite. Such a block, once a down- 

 wardly projecting part of a roof in stock or batholith, may be named a 

 "roof pendant;" it is analogous to the pendant of Gothic architecture. 



A brief digression on this conception may be permitted. Unusually 

 fine examples of roof pendants are illustrated in the great slabs of bedded 

 rocks interrupting the areas occupied by the batholiths of the Sierra Ne- 

 vada. One of the most recent descriptions is published by Messrs Knopf 

 and Thelen, following the lead of Lawson in a study of Mineral King, 

 California.* Other examples, so well treated by Barrois, were found dur- 

 ing the detailed geological survey of Brittany, f In all these and many 

 other cases, and yet more clearly than on the 49th parallel, the masses of 

 country rock (invaded formation) form respectively parts of a once con- 

 tinuous roof. The often perfect preservation of the regional strike in 

 each of many examples very strongly suggests that these slabs have not 

 sunk independently in their respective magmas. Such partial foundering 

 would have almost inevitably caused some twisting of the block out of its 

 original orientation. Granite and block have come into present relations 

 because the magma, and not the block, w^as active. The point is of im- 

 portance, as it bears on the mechanics of intrusion in these instances. It 

 is further worthy of note that determination of roof pendants and their 

 distribution may sometimes lead to the discovery of the approximate con- 

 structional form of batholiths. 



A small pendant, composed of amphibolitic and micaceous schists and 

 of quartzite, occurs on the north slope of Horseshoe mountain ; another of 

 similar constitution flanks the summit of Snowy mountain. 



In all three cases the pendants appear in the highest portions of the 

 batholith as now exposed in the belt; yet each block projects downward, 

 deep into the heart of the granite mass. 



A long slab of gabbro, ranging with the Cathedral fork of Ashnola 

 river, is similarly a roof pendant to the Kemmei batholith; it may be 

 called the Ashnola gabbro (see figure 5). A still larger pendant, com- 

 posed of gabbros and peridotites, lies in the Eenimel batholith just west 

 of the main valley of the Ashnola. On account of the extraordinary 

 diversity of rocks and of rock structures in this pendant, it may be called 

 the "Basic complex" (see figure 6). 



Northeast of the complex is an elliptical stock of biotite granite, intru- 

 sive into both the Remmel granodiorite and the Basic complex. The 



♦Bulletin of the Department of Geology, University of California, vol. iii. no. 15, 1904, 

 and vol. iv, no. 12, 1905. 



f C. Barrois : Annales, Societe Geologique du Nord, many volumes, especially vol. 22. 

 1894, p. 181. 



