584 



MISS M. M. OGILVIE [mRS. GOEDON] ON THE [Aug. 1 899, 



have now to ascertain what changes were induced in this region 

 of Middle Triassic disturbance during the Tertiary epoch of Alpine 

 uprise. 



Cherz Hill over thrusts. — The accompanying diagrammatic 

 sketch (fig. 9) shows an exposure observed among the rocks above 



Fig. 9. — Cliff-exposure in the southern face of Cherz Hill, towards 

 Varda, shoiviiig the origin of the so-called Buchenstein agglomerate. 



S=:Seis Limestone. \^ n FD= Fault-dyke. 



C = Campil Sandstone I o ,. Agg=rShear-and-contact breccia (so- 



and Shale, I * called Buchenstein agglomerate). 



B=Buchenstein banded limestone MK = Musclielkalk. 



and plant-bearing shales. 



[All the rocks are altered at the zones of contact ; the Werfen strata are 

 crushed and streaked into the ' agglomerate ' at some points ; the Muschel- 

 kalk is broken up into huge wedges of ' agglomerate ' or dragged out into 

 brittle paper-like laminse ; the Buchenstein limestone and shales have 

 been changed into black earthy or banded rocks ; while green ' pietra verde ' 

 and other highly altered rocks mark the zone of Buchenstein rocks actually- 

 next the main fault-dyke.] 



Varda. Werfen strata and Muschelkalk occur here below the 

 augite-porphyrite of Cherz Hill, at a height of 1000 feet above 

 their exposure in the valley at Soraruaz, and are overthrust 

 above the augite-porphyrite of the Arabba area. The overthrust- 

 plane hades northward. 



Contact- and fault-alteration. — The overthrust series of 

 rocks have been greatly compressed and sheared, the fossils found 

 in the Werfen strata being squeezed and distorted. Patches of 

 Werfen strata and greater masses of Muschelkalk have been rolled 

 together with the intrusive rock into a shear-and-contact breccia. 

 Here, as elsewhere, this mechanical complex has been regarded as 

 a sedimentary series, the so-called ' Buchenstein conglomeratic 

 limestone.' Pig. 9 displays the true relation of the rocks to the shear- 

 and-contact breccia particularly well, since it shows wedges of 

 various horizons, more especially large blocks of Mendola Dolomite 



