ATLAS · EnerTchad
Basins and fields
Explore the geological setting, basins, fields, reserves and educational volumetric estimator.
1Geological frame
Chad’s subsurface belongs to the Central African intracontinental rift system, formed in the Early Cretaceous along the Central African Shear Zone (CASZ). Extension created a series of half-grabens — Doba, Bongor, Doséo, Salamat and Termit — filled with lacustrine and fluvial sediments rich in source rocks.
The reservoirs are mainly Cretaceous sandstones (syn- and post-rift) between 1,000 and 2,500 m deep; locally, fractured granitic basement forms a secondary reservoir (Bongor basin). Crudes range from heavy and discounted (21–24° API at Doba) to lighter (~31° API at Bongor).
2Sedimentary basins
Cretaceous rifting opened five major half-grabens — those in the table below; the registry, for its part, maps seven basins, adding Madiago and Erdis (Kufra). Doba and Bongor concentrate the production; the others form the exploration frontier of the 2025-2030 plan.
| Basin | Status | Reservoirs | Crude | Note |
|---|---|---|---|---|
| Doba | Production | Cretaceous sandstones 1,200–1,800 m | 21–24° API | Historical production heartland |
| Bongor | Production | Syn-rift sandstones + fractured basement | ~31° API | Feeds Djermaya |
| Doséo | Appraisal | Cretaceous sandstones | light | EOR by water injection |
| Salamat | Frontier | Cretaceous sandstones (presumed) | — | South-East · exploratory half-graben |
| Termit | Frontier | Syn-rift sandstones | — | West · prospective graben |
| GRADE | API | SULPHUR | TAN | OUTLET |
|---|---|---|---|---|
| Doba Blend · Komé, Bolobo, Miandoum | 21-24.5° | 0.14% | 4.7 mg KOH/g · acidic | Kribi FSO export · discounted vs Brent |
| Ronier Blend · Rônier, Mimosa | 28-32° | 0.05% | < 0.5 | Djermaya refinery · domestic market |
| Sédigui Condensat · Kanem | 45-55° | < 0.02% | — | Petrochemicals & blending (targeted) |
The Doba Blend’s high TAN (naphthenic acidity) demands adapted refining metallurgy — a key parameter in our mini-refinery choices — and explains part of the export discount. Sector data, to be consolidated by assay.
The historical production heartland (since 2003) over ~200,000 km², separated from the Bongor basin by a basement high within the Central African rift. Cretaceous sandstone reservoirs at 1,200-1,800 m. Komé, Miandoum, Bolobo, Badila and Mangara fields. Heavy 21-24° API crudes, discounted against Brent — hence the stake of enhanced recovery. Estimated reserves 170 Mt.
A NW-SE half-graben born of the Central African Shear Zone (~16,000 km²), marked by strong tectonic inversion. Syn-rift sandstone reservoirs (Prosopis, Kubla-Ronier) and fractured granitic basement (Baobab, Daniela accumulations). Ronier, Mimosa, Baobab and Koudalwa fields, linked to the Djermaya refinery by the Ronier-Djermaya pipeline (300 km, 2011). Lighter crudes, up to 31° API.
South-East. Improved recovery by water injection (+10%). Synergy with Doba. Progressive development.
Western Chad · Termit graben (Niger border). A prospective syn-rift system, early exploration — high risk, high reward.
South-eastern Chad. An exploratory Cretaceous half-graben, continuous with the rift system. Seismic acquisition to be scheduled; blocks open on the registry.
3Chad’s producing fields
Production is historically concentrated in the Doba basin (Komé, Miandoum and Bolobo fields, operated since 2003) and in the Bongor basin, whose crude feeds the Djermaya refinery through the Ronier–Djermaya pipeline. The Badila and Mangara fields round out the South’s productive portfolio.
| Field | Basin | Status | Outlet |
|---|---|---|---|
| Komé | Doba | Production (2003) | Export Kribi |
| Miandoum | Doba | Production | Export Kribi |
| Bolobo | Doba | Production | Export Kribi |
| Badila | Doba (South) | Production | Export Kribi |
| Mangara | Doba | Production | Export Kribi |
| Ronier | Bongor | Production (2011) | Djermaya refinery |
| Mimosa | Bongor | Production | Djermaya |
| Baobab | Bongor | Production (basement) | Djermaya |
| Koudalwa | Bongor | Production | Djermaya |
| Sédigui | Lake Chad area | Discovered, undeveloped (crude and gas) | Gas-to-power |
From field to export. The southern fields converge on the Komé hub (Doba), entry point of the Doba–Kribi (≈ 1,070 km) export corridor down to the Kribi terminal — the country’s oil artery. EnerTchad owns none of these assets: a start-up company, it describes here the Chadian sector in which it positions itself as a service provider.
4Reserves & resources
Reserves are classed by their probability of recovery (1P/2P/3P). Enhanced oil recovery (EOR) is the main lever for extending the life of mature fields.
| Category | Volume | Definition |
|---|---|---|
| 1P — Proven | ~1.5 Gboe | Probability ≥ 90%, fields in production |
| 2P — Proven + probable | ~2.8 Gboe | Probability ≥ 50% |
| 3P — + possible | ~4.2 Gboe | Probability ≥ 10% |
| Life index (R/P) | ~28 years | Extended to 38+ years through EOR |
High confidence, fields in production.
Likely to be recovered (1P + upside).
Subject to technical & fiscal approval.
Extended to 38+ years through EOR (+0.6-0.8 Gbbl).
5Volumetric estimator (STOIIP)
A teaching tool: adjust the reservoir parameters to model the stock-tank oil initially in place (STOIIP) and the recoverable volume of a typical prospect. The recovery factor — often 10 to 35% in primary — is precisely what enhanced recovery (EOR) sets out to raise.