Yol. 55.] THE TORSIOIf-STRrCTUKE OE THE DOLOMITES. 573 



Fault on the western slopes of the Groden Pass. The transverse 

 dykes in both cases mark a strongly -twisted branch fault, run- 

 ning in a northerly, north-north-westerly, or north-north-easterly 

 direction across the anticline. The twisted faults probably served 

 to relieve the tension in areas where the strike-faults were tending 

 to converge and even to intercross. 



The distinctly ' knee-bent ' sbape of the Groden Pass Anticline 

 on the eastern slope is shown in fig. 6, p. 572. The northern wing 

 has been overthrust south-south-eastward upon the ' reversed ' fault- 

 plane, and intrusive rocks have been injected not only into the 

 normal and reversed limiting-faults, but also into the associated 

 transverse and oblique dislocations. 



The'Colfosco section of the Groden Pass Anticline. — 

 The Colfosco (Kollfuschg) portion of the Groden Pass Anticline is 

 also limited to the ' knee-bent ' strata of the northern wiug, the full 

 form of the anticline not appearing until the valley-level is reached 

 below the hamlet of Pescosta. 



The steep pastoral hill-ground between the hamlets of Colfosco 

 and the cliffs of Tschampatsch and Sass Songe is composed of the 

 lowest Wengen horizons, Upper and Lower Muschelkalk, Campil 

 and Seis strata. The various horizons are met as one descends to 

 Pescosta, the margin of outcrop representing the southern fault of 

 the ' knee-bend/ The Mendola Dolomite is greatly cut up by dykes,, 

 whose direct connexion with the fault-sill B can be actually seen 

 in tracing them both eastward to the stream-cutting above Colfosco. 

 Contact-breccia again marks the contact-zone of the sill with the 

 Mendola Dolomite, and patches of recognizable Wengen strata are 

 found amid the sheared series between the fault-planes. 



The Wengen strata north of the fault B are perpendicular, 

 and highly altered near the intrusive rock. They form a contorted 

 fragment, cut off" against Cassian strata a ad Schlern Dolomite to the 

 north by another normal fault hading northward. 



Diagonal faults of the east side of the Groden Pass. — 

 The Pass segment is separated from the Enneberg Valley segment 

 by an important diagonal fault passing from the west side of Sass- 

 Songe (Sett Sossander) in a north-north-westerly to south-south- 

 easterly direction through Pescosta to Corvara. The fault-fissure 

 is occupied by a thick mass of intrusive rock, the chief outcrop 

 of which crosses eastward from the Pescosta slopes to those of 

 Langs-da-Fiir between Corvara and !St. Cassian. But dyke-threads 

 may be said to radiate from the Pescosta centre in all directions. 

 The chief threads are those which run westward into the Pass fault,, 

 and southward and south-south-eastward towards Corvara, Artara, 

 and Campolungo. A branch of the southerly fault twists south- 

 south-westward at the bend of the Rudort stream and continues as 

 the chief fault east of Sella, with a westerly downthrow towards that 

 mountain. Another branch continues the north-north-westerly to 

 south-south-easterly direction of the Pescosta-Corvara Fault, has an 



