POSITIONS OF ANCIENT CONTINENTS 369 
In China, Richthofen, Pumpelly, and Willis have found a uni¬ 
form northeast direction in the basement complex, which was com¬ 
pletely folded and again abraded before the Cambric submergence. 
This northeast direction (the Sinian system of Richthofen and 
Pumpelly) continues through Korea, and Suess has shown its 
complete domination in all northeastern Asia east of Lake Baikal 
(his “Baikal direction’^), which is eastnortheast-northeast. This 
meets, in a meridional line, the “Sajan direction” of Pre-Cambrian 
folds, which is westnorthwest to northwest and prevails west of 
Lake Baikal through all northern and middle Asia, Russia (Kar- 
pinski), and the Baltic shield, the latter being only a larger 
northern exposure of the Russian Pre-Cambrian plate. The latter 
extends through northern Europe much disturbed by later folding 
and probably abuts against the Laurentian plate in western Scot¬ 
land. 
In North America the Canadian shield exhibits in its eastern 
portion a uniform northeast direction of the folds (Adams and 
Coleman). This direction continues through Greenland with some 
variation to northnorthwest along the coast of Labrador, through 
Tertic crustal movements (Adams), and it is even recognizable 
on the western edge of Scotland. It is further observed in several 
ways, as in the interlocking northeast-southwest bands of different 
gneisses, shd’mng ancient folding (Keith) in the southern exten¬ 
sion of the Pre-Cambrian basement complex in the Appalachian 
and Piedmont systems. In the western part of the Canadian shield,' 
north of Lake Superior, the Pre-Cambrian folds have assumed an 
east-west direction. Likewise the outcrops of Pre-Cambrian rocks 
south of Lake Superior, in Wisconsion, show a predominant east- 
west direction. In the Ozark Mountain. Pre-Cambrian nucleus, 
however, a northwest direction (strike N 50°W) is already recog¬ 
nizable; likewise in the Black Hills and farther south in the Ar- 
buckle uplift in Oklahoma (strike westnorthwest) and in Texas, 
in Burnet County; where a monadnock of the ancient Lauren¬ 
tian land projects, with a northwest strike of the major folds in 
the Pre-Cambrian rocks. In the southern Rocky Mountains the 
Pre-Cambrian masses strike from south to north but exhibit a 
tendency to turn northnorthwest to northwest. 
It thus appears that there can be recognized in the Pre-Cambrian 
