for hydrocarbons

OPEN ROUND COLOMBIA 2010

URABA AREA

January, 2010

Total Hectares994.895

Seismic Lines WellsTotal Km Total206 3.874 5

Urabá Area

Urabá Blocks

Basin data

BLOCKS AREA (Ha)

URA 1 220693

URA 2 444198

Regional Tectonic Framework

1629-1X

Necocli-1

Apartado-1

Chigorodo-1

Apartado -1 Well Chigorodo -1 Well

AGENCIA NACIONAL DE HIDROCARBUROS

OverviewUrabá Basin

General Surface Geology

Faults and structural lineaments by accumulated number rose diagram

Uraba Basin suggested geologic column. Modified from Fllinch (in Bertolini et al, 2003) based on the description provided by ECOPETROL, 1982a.

Necoclí -1

Apartadó -1

Chigorodó-1

Reservoir RockReservoir Rock Source RockSource Rock Seal RockSeal Rock

Petroleum GeologyStratigraphic Columns

Apartadó-1 WellApartadó-1 WellChigorodó-1 WellChigorodó-1 Well

Wells and Seismic Lines Uraba Basin

Necoclí -1

Apartadó -1

Chigorodó -1

LEGEND

Wells___ Seismic line

Urabá-1

Turbo-1

1629-1X

Bouguer Anomaly Map

LEGEND

___ Contour Interval (20 mGal)

Seismic line 79-18

Representative Seismic Urabá Basin

Seismic line 79-18-5

Representative Seismic Urabá Basin

Representative SeismicUrabá Basin

Seismic line 13-5

Seismic Structural Interpretation

Organic GeochemistryNecoclí -1 Well

MIOCENE

0 50 100 150 200 250

Oxygen Index (m g CO2 / gTOC)

0

100

200

300

400

500

Hyd

rog

en In

dex

(m

g H

C /

gT

OC

)

I II

III

IV

Source Rock QualitySource Rock Quality Thermal MaturityThermal Maturity

Prospectivity

The wells drilled allow identifying several sandstone intervals in the sedimentary sequence, which could be reservoirs. The claystones interbedded in the sequence could act as local/regional seals. Normal faults create structural-stratigraphic traps by onlap/juxtaposition against the basement, and to the W-SW stratigraphic traps by onlapping on the basement.

In the eastern margin of the basin the development of compressional folds close to the Uramita Fault are observed.

• The geochemical information (Necocli-1 well) is insufficient to corroborate or rule out the existence of proper conditions for hydrocarbons generation in the basin. It is also not possible to characterize any of the informal stratigraphic units as potential source rock.

• Regarding the reservoirs, the wells information shows the deposit of sandstones interbedded with claystones and siltstones along all the drilled sequence in the Apartado-1 and Chigorodo-1 wells. This implies that practically all the units in the basin could be potential reservoirs.

• Regarding the plays in the area, the seismic information indicates that the basin is tilted to the northeast and has flexural geometry. This flexure causes the development of normal faults that generate structural highs against which the sediments in the basin are truncated/onlapped, especially the deepest units (Units C and D). Due to the progressive basement’s shallowing towards the southwest; the more recent sediments overlap or pinch out against the basement in that direction creating potential stratigraphic traps.

Conclusions

Germán Vargas CuervoMsc - Ph. D.

Project Manager

Luis Castillo lópezMsc - Ph. D.

Roberto AguileraConsultant Geologist

Diana M. JiménezANH Supervisor

Universidad Nacional de ColombiaWork Team

www.anh.gov.co