Generación de petróleos y carga de reservorios en Manantiales Behr, Cuenca del Golfo San Jorge: un caso de exploración en áreas maduras

JALFIN G., E. BELLOSI, E. SMITH Y G. LAFFITTE

Mar del Plata

Congreso; 5° Congreso de Exploración y Desarrrollo Hidrocarburos; 2002

Instituto Argentino del Petroleo

Four main kitchens (Granson, Diadema-Escalante, Cafladon Perdido and Caflad6n Botella) were recognized as responsible for filling the Manantiales Behr's traps. The expulsion started at 65 Ma in Granson kitchen from a Neocomian source rock, and since 50 Ma from Diadema-Escalante kitchen from Neocomian + D-129 beds. The expulsion rim reaches Caflad6n Perdido kitchen at 40 Ma. The oil generative system was totally developed at 30 Ma, where even the Neocomian sequence at Caflad6n Botella kitchen gets the oil window.The continued subsidence of the Neocomian + D-129 at Granson kitchen leaded to the first expulsion of very light oil/gas/condensate at 20 Ma, which played a main role in the solubilization of oils previously reservoired and biodegraded. The main superficial water invasion occurred at 40 Ma (hiatus between Sarmiento-No Chico Formations). The presence of this pulse marks the difference between the producible oils from the dead oils (<lOOAPI). The remaining expulsed oils from Granson kitchen filled the deeper reservoirs (top of D-129 closures). Finally, Diadema-Escalante kitchen in the last 10 Ma expulsed verylight/gas/condensate, filling the southernmost traps against Escalante lineament. This predictive model of the migration pathways, accompanied by the history of the reservoir filling, has been achieved from the integration of sedimentological, structural and geochemical studies. The drilling of the sweet spots suggested by this model has leaded to the discovery of light oils from deeper reservoirs (lower Mina del Carmen and upper Pozo D-129 Fms.) in two new blocks (La Carolina and Granson). The successful exploration of remote areas and deeper reservoirs has triggered an aggressive development plan resulting in both a significantincrement in the daily production and the revalorization of the field with the incorporation of new proved reserves.