Author: Marcel Chin-A-Lien – Petroleum & Energy Advisor
Date: 27 April 2026

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Statement

It is fundamentally unknown how much total petroleum has been generated in any basin, including the Guyana–Suriname Basin (GSB).

Geological uncertainty, incomplete data, and complex petroleum system processes make absolute quantification impossible.

However, what is known with high confidence is the volume of hydrocarbons already discovered.

These discoveries provide a robust and defensible anchor from which the minimum hydrocarbon generation required can be reconstructed.

This study demonstrates that the GSB must have generated at least several hundred billion barrels of oil equivalent, and likely significantly more, in order to account for existing discoveries.

This provides a solid foundation for estimating remaining exploration potential.

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1. Introduction

The Guyana–Suriname Basin has emerged as one of the most important new hydrocarbon provinces globally.

While discoveries have been substantial, basin-scale petroleum system quantification remains uncertain.

This paper addresses that uncertainty by applying a discovery-anchored reconstruction approach, focusing not on speculative total resource estimates, but on what must have occurred geologically to produce the volumes already proven.

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2. Methodological Principle

The central concept is straightforward:

Discovered hydrocarbons represent only a fraction of the total hydrocarbons generated.

By estimating realistic system efficiencies (expulsion, migration, trapping), we can reconstruct the minimum hydrocarbon generation required to produce observed discoveries.

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3. Observed Discovery Base

Component	Recoverable	Estimated In-Place
Oil	~12–15 Bn bbl	~40–45 Bn BOE
Gas	~4–5 Bn BOE	~5–6 Bn BOE
Condensate	~0.5–0.7 Bn BOE	~1–1.5 Bn BOE

Total discovered in-place: approximately ~50 Bn BOE

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4. Minimum Hydrocarbon Generation

Petroleum systems are inherently inefficient. Only a small fraction of generated hydrocarbons is ultimately trapped and discovered.

Efficiency Scenario	Implied Generation
High Efficiency (~10–12%)	~400 Bn BOE
Moderate Efficiency (~6–8%)	~600–800 Bn BOE
Low Efficiency (~3–5%)	>1,000 Bn BOE

Conclusion: Even under conservative assumptions, the Guyana–Suriname Basin must have generated on the order of 400–700 Bn BOE, with higher values entirely plausible.

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5. Phase Considerations

The basin is not purely oil-dominated. Instead, it represents a dual-phase petroleum system.

Phase	Estimated Share
Oil	50–60%
Gas	30–40%
Condensate	~10%

This implies a very large gas generation system, much of which remains under-explored and under-recognized.

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6. Remaining Exploration Potential

Because discovered hydrocarbons represent only a fraction of the total generated, a significant portion of the basin’s petroleum system remains either:

• Undiscovered (trapped but not yet drilled)
• Untrapped (still migrating or dispersed)
• Technically unrecoverable

Based on the reconstructed generation system, it is reasonable to conclude:

• Current discoveries (~50 Bn BOE in-place) represent only a partial realization of basin potential
• Substantial additional discoveries are likely, particularly in underexplored domains
• Gas and condensate systems may represent the largest remaining opportunity

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7. Strategic Implications

7.1 Basin Scale

The GSB must be understood as a large-scale petroleum system, comparable to major Atlantic margin basins.

7.2 Oil vs Gas

While oil discoveries dominate current narratives, the underlying system indicates a significant gas component.

7.3 Development Pathways

The ultimate value of the basin will depend not only on resource size, but on how hydrocarbons are monetized:

• Oil: FPSO-based export systems
• Gas: LNG export vs Gas-to-Shore development

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8. Key Insight

The most important conclusion is not the exact volume generated, but the scale of the system required to produce existing discoveries.

This scale alone demonstrates that the basin remains far from fully explored.

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9. Conclusion

• Total hydrocarbon generation in the GSB is inherently uncertain and unknowable in absolute terms
• However, discovered volumes provide a reliable lower bound
• This lower bound implies a basin-scale generation system of several hundred billion BOE
• Significant additional hydrocarbons likely remain to be discovered

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Final Statement

While the total petroleum endowment of the Guyana–Suriname Basin will never be known with certainty, the scale of already discovered resources provides a compelling and defensible basis to conclude that the basin is a major, still maturing petroleum system with substantial remaining potential.