In recent years deepwater exploration in the Caribbean has seen considerable success with Anadarko’s Gorgon, Kronos and Purple Angel gas discoveries offshore Colombia and ExxonMobil’s oil discoveries Lisa, Longtail and Turbot offshore Guyana. The move into the deeper waters has opened up a number of countries that were considered to be un-prospective or of limited prospectivity. BHP Billiton have licenced acreage offshore Barbados, Tullow have recently completed a 3D seismic survey in Jamaica and the Russian Global Petroleum Corporation reportedly made a commercial discovery in Grenada with the Nutmeg-1 Well in March of this year. Has Aruba joined the list of Caribbean exploration success stories?

On the 9th July the drill ship West Capella moved off location, 53 km to the north west of the Caribbean island of Aruba. She spent some 30 days drilling the Bon Bini Prospect for Repsol and partner Total in approximately 538m of water. To date no press release has been issued by the operator. The Bon Bini Prospect has a Tertiary carbonate objective similar to the giant Perla gas discovery located to the south in Venezuelan waters.

The Aruba Production Sharing Contract (PSC) signed with the state oil company Compania Arubano di Petroleo (CAP) is a 50/50 joint venture with Total. We believe that the BG Group had farmed into the licence for a 33% interest, but Shell elected to withdraw at the time of the takeover.

Prior to the activities of Repsol, a coarse grid of 2D seismic and three wells had been drilled in the 80s and early 90s. The three wells Mero-1 (Maraven), Divi Divi-1 (Hamilton) and Chucchubi-1 (OXY) were drilled between 1989 and 1990 in the Aruba Basin, to the southwest of the island. The Aruba Basin is one of several pull apart basins, such as the Falcon Basin located off the northern coast of South America. All three wells encountered a monotonous section of Oligocene (possibly latest Eocene) to recent sediments consisting mostly of clays and shales sitting on Cretaceous oceanic basement (E.A. Curet). On the basis that the source rocks were low TOC, gas prone type III Kerogen and immature combined with the fact that no significant reservoir rocks had been encountered in the three wells, Curet concluded that the petroleum potential of the Aruba Basin was limited.

The catalyst for Repsol’s interest in this area was probably the giant Perla Field located some 89 km to the south west of Aruba in Venezuelan waters, which they discovered in 2009. The 17 TCF gas field was then the largest in South America and came onstream in 2015. It is operated by Cardon IV SA a 50/50 Joint venture formed by Repsol and ENI. Importantly the field proved a Tertiary thermogenic petroleum system, which presumably Repsol are chasing in Aruba. The reservoir in the field consists of upper Oligocene to early Miocene limestones which have been enhanced significantly by leaching (Castillo et al). A column height has been of 350m has been proven and the area of the predominantly structural trap exceeds 100km2 (Castillo et al). In early 2016 the field was producing 510 MMSCF/D and 13857 b/d of condensate.

We understand that Repsol have demonstrated the presence of a thermogenic petroleum system in Aruba with an extensive piston coring programme. This was followed by the acquisition of more than 3500km of 2D seismic and 3300km2 of 3D seismic. We believe that the Bon Bini-1 well tested a carbonate objective similar in age to the Perla Field.

Please let us know if you have heard anything regarding the well results.

This blog represents the personal opinions and views of the author and does not necessarily reflect the views of MapStand

References:

Castillo, V, Benkovics, L, Demuro, D, Franco A, 2017, Perla Field: The largest discovery ever in Latin America, in R.K.Merrill and CA Stembach, eds., Giant fields of the decade 2000-2010 AAPG Memoir 113, p141-152.

Curet, E.A, Stratigraphy and Evolution of the Tertiary Aruba Basin, Journal of Petroleum Geology, Volume 15, Issue 2, April 1992 p283-304