Petroleum System of the Northern and Central Bolivian Sub-Andean Zone

摘要: A coupled study of the kinematics thrusting and hydrocarbon maturation has been carried out in northern central sub-Andean belt Bolivia to define petroleum potential area. In addition classic Devonian source rock (Tomachi-Tequeje formations north Iquiri-Limoncito area), two other intervals are recognized: Retama Formation (Upper Devonian-Lower Carboniferous) Copacabana Carboniferous-Lower Permian). These most prospective units marine origin. The structural style varies from south due variations sedimentary column involved thrusts. orogenic front was guided by boundary a Paleozoic wedge. Boomerang area, this is oriented obliquely regional shortening controlled development prominent transfer zone. To north, thrusts wider amount increases. western part zone characterized very thick Tertiary piggyback basin fill. Two phases recognized. first began Early Carboniferous affected mostly strata. traps during period occurred rarely. entire then deeply eroded Permian-Jurassic time, causing any hydrocarbons that may have formed be lost. second phase contemporaneous with Andean deformation resulting burial under cover foreland basins on thrust structures. expelled fill anticlines. known rocks not proven gas prone, but current discoveries indicate high oil ratio secondary cracking rock. Because initial low, expulsion heavy compounds expected weak.