334 



(.lit off ll>e E- W strikes of North-Formosa at a right angle and 

 separate the Sakishinaa Islands from each other and from Formosa- 

 According to our conception of tlie differences in cliaracter and 

 rate of movement at different depths, the absence of islands t)etween 

 Formosa and the Sakisiiima Islands ma}' he looked npon as i-esnlting 

 from the formation of gaping fractures, in connection with the 

 velo(Mtj-differences in a horizontal direction at the surface near the 

 bending-point, and from a minimum elevation of the geanticline near 

 the bending-point of the horizontal projection of the axis. The ab- 

 normal strikes of the Sakishima-Islands find an explanation in the 

 assumption of movements, such as have been referred to above in 

 the discussion of a geanticlanal movement with curving older strikes 

 and with a displaced bending-point in the final stage (Fig. 5). The 

 movement can be described only in broad outlines, the details can- 

 not be derived from the visible facts. Thus the strikes on the Saki- 

 shima-lslands have no constant direction, and differences occur between 

 the strikes of the older and those of the more recent deposits. Near 

 the bending-point, however, irregular movements can be expected, 

 while at the same time the rate of vertical movement, and conse- 

 quentlj the rate of erosion must i)i a high degree have influenced 

 the present-day tectonic structure. 



The abnormal strikes of the Sakishima-Islands have been explained 

 differently by von Richthofen ^), who speaks of transverse subsidence 

 causing an abnormal dip of the strata in connection with his ex- 

 planation of the origin of the mountain arcs of Eastern Asia by 

 tensional and not by compressional stress. In contradistinction to 

 this interpretation by vertical movements, we have compared the 

 features with those of other belts of islands and find an explanation 

 of the abnormal strikes near the bending-points of the geanticlinal 

 axis in considerable horizonial movements, which have already been 

 discussed by us for various geanticlines in connection with other 

 features. 



^) F. VON RiCHTHOFRN, Geomorphologische Studiën aus Ost-Asien. III. 8itz. 

 Ber. Akad. d. Wiss. Berlin. Phys.-math. klasse. 1902, p. 944 et sec. 



