214 r. B. TAYLOR ORIGIN OF THE EARTH's PLAN 



southeast. They seem to show some affinity for Australia and at the 

 same time are somewhat independent. Samao, like Fiji, seems to be a 

 l)oint of intersection for lines from the north and the east. These eastern 

 lines seem to show no affinity for South America and very little for Aus- 

 tralia, but are perhaps related more closely to a submerged crustal sheet 

 lying to the south. 



BORNEO, CELEBES, AND HALMAHERA 



The peculiar mountain plans of these three islands have attracted the 

 attention of geologists for more than a century, and the explanation of 

 them has remained a puzzle. Their forms are shown in some detail in 

 figure 8, but their relations to the trend-lines of the peripheral ranges are 

 better shown in figure 2. 



It will suffice for the present to point to the fact that they occur just 

 where the advancing folds of Asia and Australia came into confiict (see 

 figure 2). In each of these islands we seem to see a fold belonging to 

 the southeast part of the Malay lobe advancing broadside against the 

 end of one or more Australian folds, and both sets of folds are affected 

 by the encounter. Celebes seems to show the simplest relations. The 

 Malay fold appears to have been retarded and its trend-line indented by 

 the Australian fold, while the Australian appears to be broken and re- 

 flected back. The mechanics of these forms, however, are not yet clearly 

 understood. 



The plan of Borneo strongly resembles that of Celebes, but it has been 

 elevated so that its platform is above the sea. Halmahera is also a min- 

 iature of the same type. 



Another point illustrated here is that where the Tertiary belt has 

 several ranges, not only were the back ranges made first, but during the 

 later folding of the front ranges the back ranges were subjected to a move- 

 ment of elevation without further folding. Borneo is largest and high- 

 est, Celebes smaller and lower, and Halmahera still more reduced. We 

 seem to see also a dying out of intensity from Borneo to Halmahera. Is 

 it not significant that these strange forms occur just here at the point 

 of confiict between the Tertiary mountain belts of Asia and Australia ? 



Suess calls these forms "chiragratic,'^ and places Chalcidyce and 

 Morea of the Dinaro-Tauric arc in the same class (I, 506). The latter 

 are peculiar, but they are not the same as the Malay forms, and were not 

 produced in the same way — that is, by a broadside-to-end conflict of 

 folded ranges. 



SOUTH AMERICA 



In the present state of knowledge there is not much to say about this 

 continent, for it is decidedly the most abnormal of any that were affected 



