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alluvium is spread over a large part of the old ground, whereas here’ 
the new alluvium which is spread over the surface is small, but slowly 
the whole is worked over and turned under by this lateral cutting and 
deposition of the streams. 
In these coves all the contours are gentle and rounded, save at the 
lower ends, where the streams usually issue through picturesque gorges. 
Just as the scenery of the Cordillera is wild, rugged, and forbidding, so 
here is it mild, domestic, and inviting. Plate VII is a view looking 
eastward over the Carmen Valley; the mantle of coral limestone on the 
hills across the valley should be noted. 
THE COASTAL PLAINS. 
Cebu throughout most of its extent has remarkably little coastal 
plain, and yet it is this exceedingly narrow and interrupted strip which 
supports her proportionally enormous population. It has a foundation 
of coral reef on which has been deposited the débris of the hills, Pied- 
mont River deposits. In this débris is material from the decay of all 
manner of rocks—diorite, andesite, basalt, sandstone, and limestone— 
through and over which the streams have worked their way from the 
highlands to the lowlands. The gathering together of all these constit- 
uents in the plain soils has rendered them very rich, as they consist of 
many varieties of elements. This raised shelf is, likewise, a result of 
manifold processes of building. With a foundation of coral rock, these 
plains have been constructed by deltas, alluvial fans of the rivers coming 
down from the mountains, and by the work of the sea, as is manifested 
by bars and spits. Undoubtedly much of the planeness of this lower 
country has been produced by wave cutting. This plain has not a 
perfectly even and uniform surface, because all these different agencies 
have left on the topography their mark which time has not entirely 
obliterated. 
To make a critical study of the coastal plain, we must review its mode, 
or modes, of origin. As islands in regions of volcanic disturbance, as 
is the case in the Philippines, emerge from the sea, usually with little or 
no coastal plain, we may begin with a hypothetical case and show the 
normal course of development of such a plain. If we neglect the part 
played by the reefs, the progress would be about as represented in the 
three diagrams (taken from Chamberlin and Salisbury).° 
® Chamberlin, T. C., and Salisbury, R. D.: Geology: Processes and their results, 
New York (1904), 1, 58. 
