The Bocono Fault Zone, Western Venezuela

Conference · Mon Feb 01 00:00:00 EST 1993 · AAPG Bulletin (American Association of Petroleum Geologists); (United States)

OSTI ID:6105558

Schubert, C ^[1]; Estevez, R ^[2]; Henneberg, H G ^[3]

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1. I.V.I.C., Caracas (Venezuela)
2. Universidad de los Andes, Merida (Venezuela)
3. Universidad del Zulia, Maracaibo (Venezuela)

The Bocono Fault Zone, the western part of the Bocono Moron-El Pilar Fault System of the southern Caribbean plate boundary, consists of aligned valleys, linear depressions, pull-apart basins and other morphological features, which extend for about 500 km in a N45[degrees]E direction, between the Tachira depression (Venezuela-Colombia border) and the Caribbean Sea. It crosses obliquely the Cordillera de Merida and cuts across the Caribbean Mountains, two different geologic provinces of Late Tertiary-Quaternary and Late Cretaceous-Early Tertiary age, respectively. Therefore, the maximum age that can be assigned to the Bocono Fault Zone is Late Tertiary (probably Pliocene). A total maximum right-lateral offset rate of 3.3 mm/a. The age of the sedimentary fill o[approximately] the La Gonzalez pull-apart basin suggests that the 7-9 km right-lateral offset necessary to produce it took place in Middle to Late Pleistocene time. The majority of seismic events are well aligned with the main fault trace; minor events are distributed in a belt several kilometers wide. Focal depth is typically 15 km and focal mechanisms indicate an average east-west compression across the zone. Return periods of 135-460 a (Richter M = 8), 45-70 a (M = 7), and 7-15 a (M = 6) have been calculated. Geodetic studies of several sites along the zone indicate compressive and right-lateral components; at Mucubaji the rate of right-lateral displacement observed is about 1 mm every 5 months (15 a of measurements).

• OSTI ID: 6105558
• Report Number(s): CONF-930306-; CODEN: AABUD2
• Journal Information: AAPG Bulletin (American Association of Petroleum Geologists); (United States), Vol. 77:2; Conference: International congress of the American Association of Petroleum Geologists (AAPG), Caracas (Venezuela), 14-17 Mar 1993; ISSN 0149-1423
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
58 GEOSCIENCES
GEOLOGIC FAULTS
GEOMORPHOLOGY
VENEZUELA
GEOLOGIC STRUCTURES
AGE ESTIMATION
COMPRESSION
CRETACEOUS PERIOD
DEPTH
DISPLACEMENT RATES
GEODETIC SURVEYS
QUATERNARY PERIOD
SEISMIC EVENTS
TERTIARY PERIOD
CENOZOIC ERA
DEVELOPING COUNTRIES
DIMENSIONS
GEOLOGIC AGES
GEOLOGIC FRACTURES
GEOLOGY
GEOPHYSICAL SURVEYS
LATIN AMERICA
MESOZOIC ERA
SOUTH AMERICA
SURVEYS
020200* - Petroleum- Reserves
Geology
& Exploration
580000 - Geosciences