WOODWORTH: GEOLOGICAL EXPEDITION TO BRAZIL AND CHILE. 93 
‘consequence of erosion. In the section which can be constructed 
from the exposures along the road from Rio Negro to Lages at the 
pass through Collectoria it is possible that a fault can be traced 
cutting off the Espigao from the main mass of trap on the south 
at the right of the section in Fig. 24. But this interpretation of the 
Fic. 24.— Section across the Serra do Espigao at the Collectoria on the road 
from Rio Negro to Lages. 
tilted beds at the bottom of the valley and the apparently lower 
level at which the trap lies south of the stream crossing demands 
a throw of the normal fault on the south side in a manner nowise 
supporting the hypothesis that the escarpment is due to a fault. 
This northerly steep dip has by some been regarded as cross-bedding 
and is stated to occur elsewhere along the trap escarpment in the 
underlying sandstones. 
Number of the trap sheets— It is stated that there are four trap 
sheets or sets of sheets in the trap mass of the Serra Esperang¢a on the 
s. LAGES CORYTIBANOS SERRA 
— Oo 
pa are , SK Sex IXKE REP ESPIGAO, 
FBO 0.0.0 04'S Ye ~ ee 
ee SS SS ns 9 OS as oS as Oo GT RY OH So 
Mi PERMIAN Wn ee See 
OEE i aaliec sy iar ae 
Fia. 25.— Cross-section of the Trap plateau from the Rio Negro to Lages. 
1 (dotted). Sao Bento beds. Triassic. 2 (right lined). The Collectoria 
trap sheet. 3 (cross lined). The Corisco trap sheet. 4. The Third 
(and Fourth?) trap sheets. 
eae ate 
north of the valley of the Rio Iguassti. In Dr. Derby’s section the 
trap is diagrammatically represented as if composed of surface flows. 
The number of flows or sheets entering into the plateau between the 
Serra do Espigéo and the sandstone area about Lages was not de- 
finitely determined by observation upon the ground but the plotting 
of the profile of the route and the outcrops of sandstones encountered 
in the trappean tract leads to the conviction that along this route 
there are at least three great sheets of trap separated by sandstone 
beds. The subjoined figure section (Fig. 25) gives the approximate 
profile and geological section along a line paralleling the road from 
