302 H. I. JENSEN. 
ness anywhere to the south of the Shoalhaven River. At 
Sassafras and everywhere on the Currockbilly Range near 
Sassafras they attain a thickness of from four hundred to 
about six hundred feet, and overlie folded rocks of 
Devonian age. They were deposited on a peneplain under- 
going slow subsidence. This is shown by the fact that the 
base of the Upper Marine in all the gorges is an almost 
even plane, parallel with the bedding plane of the coal 
measures. Occasionally but not often a slight bulge may 
be observed in the surface of this plane. 
The Upper Marine strata have a slight dip to the N.H. 
(at between 2° and 5°), their tilt being almost the same as 
the general slope of the country. At Sassafras Hill the 
dip becomes very much accentuated: for a short distance 
it attains an angle of 20°. This local increase in dip on the 
eastern fall of the tableland, as well asits facetted appear- 
ance, suggest that here we have a sharp monoclinal fold 
accompanied by a fault. Tbe country to the east of it has 
probably been down-thrown a couple of hundred feet. The 
faulting was accompanied by those basaltic extrusions 
which cap the tableland in many places. 
On the western flank of the Sassafras tableland the 
evidence of faulting is much more marked. The tableland 
is bordered by a line of clifis beautifully facetted by canons 
of the tributaries of the Endrick River (or Bulee). On 
descending by road to Nerriga one leaves the Upper Marine 
and enters the Siluro-Ordovician formations a couple of 
hundred feet above the point where the road crosses the 
Endrick. Following the road for four or five miles one 
meets with Siluro-Ordovician slates, intrusive quartz- 
diorite, quartz reefs and basalt all the way. A couple of 
miles beyond Nerriga, sandstone cappings were again noticed 
actually occupying the same or a lower level than the base 
of the sandstones in the tableland, but still preserving 
