[&LLS] NOTES ON GEOLOGY OF TRINIDAD AND BARBADOS 119 
the east coast about five miles north of Guayaguayare at which place a 
bore-hole was put down several years ago and oil was struck. The out- 
flows of asphalt are seen along the course of the anticline for several 
miles east of the west outcrop on the shore, and also on the road to 
Siparia, where it is about five miles from the shore of San Fernando 
Bay. 
The course of the third anticline going north, extends from the 
vicinity of the Pitch Lake eastward to the east coast where it terminates 
near Mayaro point, about twelve miles north of Guayaguayare. Between 
this and the Guaypo anticline secondary folding is observed, and here 
also the presence of petroleum is well seen. Borings have as yet 
been made along this line, as far as could be ascertained, at only one 
place. 
The San Fernando anticline has a somewhat more north-easterly 
course. It apparently reaches the east coast at Manzanilla point which 
is about fourteen miles north of Mayaro point or twenty-six miles north 
of Galeota point at the south-east extremity of the island. Owing to 
extensive lagoons between Mayaro and Manzanilla points the structure 
of the rocks for this distance cannot'be determined. 
The presence of these several anticlines in the southern half of the 
island is of great interest since they may be regarded as affecting some- 
what largely the conditions for the occurrence of petroleum. The char- 
acter of the rockg is practically the same throughout, consisting of the 
ordinary shales in considerable volume with occasionally interstratified 
beds of the oil-sands, though along the crests of these at some points 
are outcrops of harder rocks which have been regarded by the Govern- 
ment geologist as indicating the presence of possibly Cretaceous strata. 
The petroleum is apparently found at several horizons, but, unfortun- 
ately, though a number of wells have been bored, more especially in the 
Guayaguayare district, but little care seems to have been taken to keep a 
careful record or log of the strata passed through, though from measure- 
ments taken in carrying on the survey the several thicknesses of the oil— 
bearing sands have been somewhat carefully ascertained. 
The most northerly occurrences of petroleum and flows of asphalt 
observed appear to be along the north side of Naparima Hill. Here in 
the streets of the town of San Fernando, in connection with the oil- 
bearing greyish sandstone which flanks both sides of the hill, the asphalt 
is seen on one of the back streets in considerable quantity, and a short 
distance north the deposits of Manjak, known as the Vistabella and the 
Marbella mines, are located. These occurrences are of great interest 
and will be described later. 
