Gato do Mato project: Shell’s deepwater gas-condensate development in Brazil’s Santos Basin

The Gato do Mato project, located deep offshore in Brazil’s Santos Basin, represents one of the most strategic gas-condensate developments in the region’s pre-salt polygon. Operated by Shell Brasil Petróleo Ltda., with Ecopetrol S.A. and TotalEnergies SE as consortium partners, the project received its long-awaited final investment decision (FID) in March 2025. Positioned for first production by 2029, Gato do Mato is expected to deliver up to 120,000 barrels per day of oil equivalent at peak capacity, contributing significantly to Brazil’s energy production and the international operators’ upstream portfolios.

Discovered in 2015 and spanning both production sharing and concession regimes, the Gato do Mato project reflects Brazil’s hybrid offshore development strategy and the growing role of multinational partnerships in exploiting technically complex but high-reward deepwater reservoirs.

Where is the Gato do Mato project located and what is its significance?

The Gato do Mato project lies approximately 200 kilometers off the coast of Rio de Janeiro in the Santos Basin, in ultra-deepwater depths between 1,750 and 2,050 meters. It covers two adjoining blocks—BM-S-54, awarded via a concession round in 2005, and Sul de Gato do Mato, secured under a production-sharing agreement in 2017. The field is classified as a gas-condensate discovery located within the pre-salt polygon, known for its exceptional reservoir productivity and complex carbonate geology.

Its strategic significance is underpinned by its location in one of the most productive offshore basins globally and by the high-quality hydrocarbons found in the region. While not as massive in reserves as Búzios or Mero, Gato do Mato plays a pivotal role in bridging Shell’s established deepwater capabilities with its transition-era production targets, given the relatively low carbon intensity expected from the development.

Who operates the Gato do Mato project and what is the ownership structure in 2025?

Shell Brasil Petróleo Ltda. is the operator of the Gato do Mato project with a 50% stake. Ecopetrol S.A., through its Brazilian subsidiary, holds 30%, while TotalEnergies SE controls the remaining 20%. The Brazilian state enterprise Pré-Sal Petróleo S.A. (PPSA) oversees the production-sharing component, ensuring state participation and regulatory compliance.

This current structure reflects post-2016 realignments, following Shell’s acquisition of BG Group and later adjustments during Brazil’s production-sharing reform era. The involvement of Ecopetrol underscores its growing offshore ambitions beyond Colombia, while TotalEnergies continues to consolidate its South American deepwater portfolio.

What are the reserves and production expectations for the Gato do Mato project?

As of 2025, the Gato do Mato project is estimated to contain approximately 370 million barrels of recoverable oil equivalent, predominantly consisting of gas-condensate. Production will be developed via a phased subsea-to-FPSO (Floating Production Storage and Offloading) system, with peak capacity expected at 120,000 barrels of oil equivalent per day.

The field will initially rely on reinjection of associated gas to maintain reservoir pressure, with export options for surplus gas still under evaluation. Production start-up is targeted for 2029, allowing the project to align with Brazil’s offshore infrastructure expansion and Shell’s upstream scheduling.

What infrastructure supports the Gato do Mato project?

The project will be developed through a newbuild FPSO designed by MODEC Inc., which was awarded the Front-End Engineering Design (FEED) contract in 2024. The vessel will be anchored at around 2,000 meters water depth using a SOFEC spread mooring system. The FPSO is designed to process up to 120,000 barrels of oil per day and will have storage capacity for up to 850,000 barrels.

Subsea wells will be tied back to the FPSO via a network of risers and flowlines. Crude oil will be offloaded via shuttle tankers, while associated gas will either be reinjected or potentially exported in later phases through regional gas transportation infrastructure, depending on downstream demand and regulatory approvals.

How has the Gato do Mato project evolved over time?

From its discovery in 2015 to the FID in March 2025, the Gato do Mato project has experienced a complex development trajectory. Initial delays were caused by overlapping regulatory regimes across the concession and production-sharing blocks. Unitization was finalized and approved by Brazil’s ANP in 2020, enabling the project to move forward under a unified development plan.

Key development milestones include:

• Environmental licensing from IBAMA for seismic activity (2019)

• Unitization agreement for BM-S-54 and Sul de Gato do Mato (2020)

• Completion of subsurface studies and appraisal campaigns (2022–2023)

• FEED contract awarded to MODEC (2024)

• Final Investment Decision (FID) by Shell and partners (March 2025)

The FID came amid a favorable window for offshore deepwater sanctioning, with Shell citing strong internal rates of return and energy transition compatibility.

What environmental and geopolitical factors influence the Gato do Mato project?

Environmental oversight for Gato do Mato is led by IBAMA, Brazil’s environmental agency, which granted early seismic and drilling licenses and is currently reviewing the final EIA for full field development. The project is designed with low-flaring operations, reinjection-based gas management, and methane emission reduction in line with global ESG standards.

Geopolitically, the project illustrates Brazil’s continued strategy of balancing foreign direct investment with domestic content obligations. The presence of three international operators—including a Latin American NOC—demonstrates a collaborative approach to deepwater development that aligns with Brazil’s 2030 energy security and export goals.

How does the Gato do Mato project impact Shell, Ecopetrol, and TotalEnergies?

For Shell, the Gato do Mato project is integral to its strategy of developing high-margin, low-cost upstream projects that support stable cash flows and decarbonization objectives. The company highlighted Gato do Mato in its Q1 2025 earnings as a sanctioned growth project capable of achieving breakeven prices below $30 per barrel.

Ecopetrol’s 30% stake represents a key move in diversifying its portfolio beyond declining onshore Colombian assets. Gato do Mato marks its entry into Brazilian pre-salt and enhances its long-term production and technological capability.

For TotalEnergies, Gato do Mato adds to its Atlantic Basin presence and complements upstream positions in Suriname, Guyana, and other parts of Brazil. The company has repeatedly emphasized its shift toward lower-carbon, high-yield deepwater assets.

What are the latest developments in 2025?

March 2025 marked the final investment decision (FID) for the Gato do Mato project, unlocking major contract awards and procurement activities. FPSO construction and module integration planning are underway, with fabrication to be split between Asian yards and Brazilian local content suppliers.

IBAMA is in the final stages of environmental licensing, with full development authorization expected in late 2025. Meanwhile, MODEC is progressing on engineering specifications for the topsides, turret, and mooring systems.

In earnings calls and investor briefings, Shell and Ecopetrol have described Gato do Mato as a core element of their near-term offshore production growth, with cash flow contributions expected by the early 2030s.

What is the long-term outlook for the Gato do Mato project?

The Gato do Mato project is expected to remain productive through the 2040s, with potential for further recovery enhancement through CO₂ injection or tiebacks to adjacent structures. As part of Brazil’s broader offshore portfolio, Gato do Mato is expected to contribute to national output stability even as global upstream development becomes increasingly selective and carbon-sensitive.

Institutional sentiment remains bullish on the project, particularly given the relatively low emissions profile, consistent project economics, and long reserve life. It is widely seen as one of the final large-scale offshore deepwater projects to be sanctioned before energy transition pressures significantly curtail new fossil fuel developments post-2030.