THE 



GEOLOGICAL MAGAZINE. 



No. XXII— APRIL, 1866. 



I. — Sketch of the Physical Geology of the Islanb of Malta. 



By Captain F. W. Hutton, F.G.S., 

 Late Deputy-Assistant-Quarter-Master-General at Dublin. 



(PLATES VIII. AND IX.) 

 r^EOLOGICAL Structure of Malta.— The Island of Malta is 

 VJT entirely composed of Tertiary aqueous rocks, whicli lie in a 

 nearly horizontal position, but which, being traversed by several 

 faults, are found at very different levels. This horizontal position 

 of the strata is interesting, as it is seldom seen in small islands 

 situated so far from the main land; and it is probably to be accounted 

 for by supposing that any unequal pressures which might have 

 occurred during the upheavals of the Island, expended themselves 

 in the production of faults, instead of inclinations and contortions of 

 the strata. 



The length of the Island is 17 miles, and its greatest breadth not 

 quite 9 miles ; it is 56 miles distant from Cape Passaro in Sicily, 

 and nearly 200 miles from the coast of Africa. On the north-east, 

 between the Island and Sicily, the water is not deep, never, perhaps, 

 exceeding 80 fathoms ; but on the south-west coast the hundred 

 fathom line runs within three miles of the coast. 

 The rocks, or strata, are divided as follows : — ■ 

 Pleistocene. — ElejpJiant-hed. (Marked E in section.) Either a 

 hard red Conglomerate, or roughly stratified beds of sand 

 and gravel, in which are found remains of ElepJias, Sus, 

 Arvicola, and Land Shells. The Conglomerate contains frag- 

 ments of a compact and almost black Limestone, unlike 

 anything now found on the Island. This interesting bed 

 has been ably described in detail by my friend, Dr. Leith 

 Adams (who had the honour of first pointing it out), in the 

 Geological Magazine, vol. ii. p. 488. 

 Miocene. — Upper Limestone. A white, or reddish, very fossil- 

 iferous Limestone, originally more than 230 feet thick, but 

 now much reduced by denudation. The upper part is hard, 

 and in places much broken, while the lower parts are softei;. 



VOL, III. — NO. XXII, 10 



