Chicontepec ISCsWed, 01/22/2014 - 09:28
Initially, PEMEX considered Chicontepec to be its best opportunity to offset declining crude oil production in the aging Cantarell field. No more than five years ago, optimistic plans included the drilling of over 19,000 wells to boost crude oil production in Chicontepec to 606,000b/d by 2027. Following a slow production increase from 26,800b/d in 2008 to 29,500b/d in 2009, as well as the scaling down of PEMEX’s Chicontepec production target for 2010 from 176,000b/d to 48,000b/d, PEMEX’s business model for the field changed. It decided to focus on value creation through the implementation of field labs operated by leading drilling and oilfield service companies. Since then, production volumes and recovery factors have been on the rise, reaching 40,970b/d in 2010, 52,787b/d in 2011, and 68,557b/d in 2012.
On December 20, 2012, PEMEX announced a call for bids to participate in Mexico’s third round of integrated contracts at six mature fields in Chicontepec. Probable (3P) reserves for the six blocks selected by PEMEX were estimated at a total of 3.2 billion boe, close to 15% of the total 3P reserves of the paleochannel of Chicontepec. The 953km2 area also held prospective resources for 976 boe with oil viscosity ranging from 27°to 44°API. To participate in this round, bidding companies needed to certify their previous experience as field operators, preferably in lowpermeability, low-pressure unconventional reservoirs, with a proved production of at least 5,000b/d. The original terms of the contracts awarded were aimed to last for a period up to 35 years, with three months designated as a transition period and up to 24 months for the initial production period. Of the six blocks that were tendered in Chicontepec, three did not receive any bids, forcing PEMEX’s hand to declare them deserted: Amatitlán, Miahuapan, and Pitepec. These three deserted fields, however, which were the fields with largest reserves in place among the six, are described below.
Amatitlán covers 230km2 located 64km northwest of Poza Rica, Veracruz. Geologically, it is located in the southcentral portion of the Tampico-Misantla Basin. Originally discovered in May 1962, the area contains the Amatitlán, Ahuatepec, Cacahuatengo, and Coyol fields. By June 30, 2012, the block had produced an accumulated 176,928 barrels of oil and 893.73mcf of gas, after the drilling of 23 wells, of which only three were then still operating. The most recent activity at the field was between 2011 and 2012, when three horizontal wells were drilled and two of them, Coyotes-423D and Coyotes-276D, were completed with multi stage fracking techniques. The first produced 400b/d of 37°API oil and 471mcf/d with a 30% water component, while the second produced 318b/d of 28°API oil and 93mcf/d with a 35% water component. PEMEX planned an exploration well in the area to look for shale oil in the Late Jurassic formation. Data from 2012 indicated the block still had 5.25 million barrels of proven oil reserves, 195.97 million barrels of possible oil reserves, and 605.81 million of barrels of probable oil reserves, with prospective resources of up to 151 million barrels. At the same time, Amatitlán is expected to still hold 7.89bcf of proven natural gas reserves, 579.60bcf of possible natural gas reserves, and 1.60tcf of probable natural gas reserves, with prospective resources up to 418bcf.
Discovered in February 1948, Miahuapan covers a 128km2 area in the south part of the Tampico-Misantla Basin that contains the Tejada field. The main producing reservoirs of the block are found within the Late Jurassic Tamán, the Early Cretaceous Tamaulipas, and the Middle Cretaceous Tamabra-Tamaulipas, with a production of 3,400b/d. The block counted 51 wells by June 30, 2012, all of which reached the Mesozoic formations. 26 of these produced oil ranging between 25b/d and 673b/d from the TamabriaTamaulipas formation, one produced 88b/d of oil from the Late Tamaulipas, one produced 1,849b/d from the Early Tamaulipas, and the last produced 195b/d of oil from the Tamán formation. This contributed to an accumulated production of the block that amounted to 42,256 barrels of oil with a 13.56% recovery factor, and 5.72mcf of gas with a 54.69% recovery factor. Remaining 2P reserves accounted for 101.35 million barrels of oil and 295.52bcf of gas.
Located in the north-northwest of Chicontepec, Pitepec is a 230km2 area in the south-center portion of the Tampico-Misantla basin. The block is comprised of the Aragón, Pastoría, and Tlacolula fields, with Aragón covering the largest area. Discovered in August 1943 with the drilling of the Aragón-1 and Aragón-2 wells, 22 wells had been drilled by June 30, 2012, of which 11 were already closed, six were blocked, and five were still operating. Its principal productive formation is the Early Tertiary Chicontepec formation, but evidence of production was extracted from the Early Cretaceous Tamaulipas formation. February 2012 was the month with the highest recorded oil production for the field at 150b/d out of its then six operating wells. By late June 2012 the field had an accumulated production of 822,807 barrels of light and superlight oil, ranging from 32°API to 40°API, and 583mcf of gas. Data from 2012 indicated that the block still had 7.91 million barrels of proven oil reserves, 233.31 million barrels of possible oil reserves, and 637.64 million of barrels of probable oil reserves. At the same time, Pitepec is expected to still hold 11.88bcf of proven natural gas reserves, 686.87bcf of possible natural gas reserves, and 1.70tcf of probable natural gas reserves.