Changing Patterns of Land Use in the Valencia Lake Basin of Venezuela
1941; Taylor & Francis; Volume: 31; Issue: 3 Linguagem: Inglês
10.2307/210177
ISSN1931-0846
AutoresRaymond E. Crist, Carlos E. Chardón,
Tópico(s)Latin American Legal and Economic Studies
ResumoThe lake, with an area of 440 square kilometers, occupies the center of a large depression of about 3000 square kilometers. With the Aragua and Tuy Rivers, it lies in a low valley, possibly downfaulted, which trends east-west for more than 200 kilometers between the Coast Range and the Serrania del Interior. The schists that form the high mountains north of the lake are probably the equivalent in age of the phyllites, schists, and slates of the Venezuelan Andes, which are definitely pre-Cretaceous. The mountain core has been intruded by acid rocks, chiefly granite, similar to the intrusives that outcrop in the Andean massif between Valera and Timotes and west of Chachopo.' The Serrania del Interior, south of the lake, is made up of intensely metamorphosed conglomerates, sandstones, limestones, and calcareous and carbonaceous shales. It is believed that all the north-central part of Venezuela was peneplained before the Coast Range was uplifted. After the peneplanation, which is of undetermined date, a general uplift took place, rejuvenating the streams. Since then relatively wide valleys and plains have developed, such as the plains of Aragua and Carabobo and, probably, the plain of Tinaquillo. The schistose rocks contain a great amount of ferruginous matter, which weathers to a deep red and stains much of the surface soil underlain by these rocks. In certain localities around the town of Valencia a thin layer of caliche covers the schists. The presence of limekilns in the region at first suggests an outcrop of limestone, but the indurated caliche is found to be full of small pieces of schist and flakes of mica. In some places along the north shore of the lake, notably at La
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