40 
THE MEDITERRANEAN NATURALIST 
they disappear beneath the water of the sea all 
along the coast. The surface of this part of the 
island takes the form of an unco dating plain in 
which the Globigerina Limestone and the Lower 
Coralline Limestone alternately appear. The latter 
crops out in the vicinity of the Lunatic Asylum, 
at Musta, on the coast of St. Julians and Pem- 
broke, the coast to the east of Licasoli, the cliffs 
at Marsa Scala, and the lower porti ons of the cliffs 
along the south coast of Malta; but in no case 
does the surface area of the outcrops exceed a few 
hundred square yards in extent, and therefore the 
area of exposed Lower Limestone bears but a 
small ratio to that of the Globigerina deposits. 
On the northern side, the depression of the dis- 
trict has submerged the coast outcrops of tin se 
beds, and the superior deposits have therefore 
been brought to the sea-level. 
It is an interesting fact to note that most of the 
principal faults of Malta and Gozo trend in the 
same direction, that is they run almost due east 
and west, and therefore are nearly parallel to one 
another. 
If the Grand Fault and the other principal 
fractures be produced in an easterly direction it 
will be found that they will all meet at nearly the 
same point beneath the waters of the sea in about 
55°. lat. 
It would appear, therefore, as though these 
fractures owed their origin to one common cause, 
and that the pressure which gave rise to them 
must have passed along the major axis of the 
islands. 
Faults at St. FauTs Bay : — 
The strata on either side of St. Pauls Bay have 
been much crushed and broken by these compres- 
sive forces. The valley is bounded on either side 
by a compound fracture, both of which extend 
right across the island, and in a direction that is 
parallel to the Great Fault and to one another. 
The fault of the northern side of the valley con- 
sists of two parallel fractures, which coalesce 
beneath Selmone and passes or. through Selmone 
Island to the eastern shore. 
The lines of disturbance may be traced right 
across the island, as they are clearly marked by a 
range of Upper Coralline Limestone cliffs, the 
sides of which have been worn into caves and fis- 
sures of ail sizes by the chemical action of the 
! atmosphere. 
The throw of the fault varies from 30° to 60’, 
i and averages about 130 feet. 
On the southern side, the line of displacement 
| is even more pronounced, and like that on the 
northern side it consists of two parallel fractures, 
j both of which abut on the western coast in the 
vicinity of Ghain-Toffiha, and, after traversing 
the island they coalesce at the head of St. Paul’s 
Bay, and finally disappear beneath the waters of 
the Mediterranean. The western extremity of 
this fault afft rds many remarkable examples of 
! the bending and crushing effect that these dis- 
| placements have had upon the strata. The area 
' that is situated between these two sets of faults 
i dips in a south-easterly direction, and is depressed 
! to such an extent that the upper beds that form 
j the bottom of the valley have been brought into 
• juxtaposition with the Globigerina Limestone 
| along the southern line of disturbance. The ave- 
j rage dip throughout the valley is about 20°, but 
| B 
at Selmone Island it is much greater. The strata 
of these islets have been -considerably tilted, in 
some instances lying at an angle of 60° with the 
horizon. Besides these two fractures there are 
numerous others of a minor character, but gene- 
rally they are but superficial rents, that have 
| probably been caused by the overstrained contor- 
i tions of the strata. 
The Melleha Faults : — 
Like St. Pauls Bay, the valley and bay of 
Melleha are bounded on either side by faults that 
are parallel to one another, and that are slightly 
inclined in a south-easterly direction towards the 
Grand Fault. The area between them has been 
depressed, and a valley has been formed the 
eastern extremity of which now lies beneath the 
waters of the Mediterranean. The fault on the 
southern side of the bay extends from the eastern 
.. to the western shores of the island. Its throw 
varies considerably throughout its length, being 
the greatest towards its extremities ; thus, below 
the village of Melleha its downthrow is about 100 
feet, while at Melleha Point and Pedum Majesa 
it is 130 feet. 
