Geological Survey Professional Paper Volume 1159-1160 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. Excerpt: ...of the clastic debris brought to the sea by the Rio Tallaboa; the west side is mostly mangrove swamp. This spit forms the east boundary of the nearly land-locked Bahia de Guayanilla, into which drain the Rio Guayanilla and the Rio Yauco. On the southwest side of the bay is the rocky Punta Verraco, but the northern and western shores of the bay are composed of clastic debris carried to the sea by the rivers and are bordered at most places by mangrove swamps or rocky headlands. West of the Punta Verraco is the rocky cliff into which Punta Ventana (fig. 24) has been dissolved. Figure 24.-Punta Ventana, a natural window dissolved in Miocene limestone at edge of Caribbean Sea, 6 km south-southwest of Guayanilla. West of Bahia de Guayanilla, rocky headlands alternate with small areas of coastal plain composed of clastic debris and mangrove swamps. At the southwest corner of Puerto Rico are the complex multiple tombolos of Cabo Rojo in which a series of sandy beaches have been shaped by currents from the east and the north, enclosing several lagoons and connecting two rocky islands with the mainland. North of Bahia Sucia are several lagoons that have been modified into salt pans in which seawater evaporates to form sea salt, sold commercially. WESTERN COASTAL PLAINS The west coast of Puerto Rico is much like the east coast in that it consists of rocky headlands, where the longitudinal mountain chains of Puerto Rico plunge into the sea, transecting wide coastal plains, where the major west-flowing rivers enter the sea. The alluvium brought in by these rivers has been shaped by long-shore currents into a number of cuspate beaches, some of which have been extended beyond the lowland areas to form narrow beaches at the foot of headlands. Mangrove swamps are...