The Subsurface Detective: Jim Clark on Solving Complex Reservoir and CCS Challenges

Jim Clark, SPE, is a petroleum engineering leader with more than 4 decades of experience in reservoir engineering, subsurface characterization, CO₂ EOR operations, deepwater development, and carbon capture and storage (CCS).

His background includes senior technical roles with major operators, independent E&Ps, and US Department of Energy-supported CCS projects. Throughout his career, he has focused on bridging classical reservoir engineering, numerical simulation, and modern analytics to improve subsurface decision-making.

For younger professionals entering the industry, Clark’s journey offers insight into how technical curiosity, adaptability, and multidisciplinary thinking can open career pathways across both traditional petroleum engineering and emerging CCS opportunities.

Habib Ouadi (HO): Can you begin by introducing yourself and summarizing your career, particularly regarding subsurface engineering and CCS?

Jim Clark (JC): Thank you. It's a privilege to share my experience, and I hope it helps early-career engineers see the range of possibilities in subsurface work.

I have roughly 44 years of experience in petroleum engineering, and in recent years I have increasingly focused on carbon capture, utilization, and storage (CCUS) subsurface strategy, simulation, and permitting. I hold two degrees in petroleum engineering from Texas A&M, an MBA, and an MS in analytics completed during the COVID-19 pandemic. The analytics background has been especially useful as our industry becomes more data-driven.

Most of my work has centered on reservoir engineering—mainly clastic reservoirs across the US and internationally, with some work in carbonates. I have worked at companies like Gulf Oil, Chevron, BHP Billiton, and Anadarko (now Oxy), as well as smaller Gulf of Mexico operators. My deepwater experience, nearly 20 years, taught me how to make decisions with limited data, relying heavily on seismic interpretation and simulation under uncertainty. Across both petroleum and CCS projects, my philosophy is consistent: integrate geology, geophysics, engineering, and economics to build static and dynamic models that help teams make high-confidence decisions. Subsurface engineering is often like solving a technical detective story—you gather evidence, identify what matters, and validate it through numerical modeling and real data.

As the field evolves, I find great value in incorporating advanced workflows such as data analytics and early forms of artificial intelligence (AI). These tools help uncover insights, speed up repetitive analysis, and allow engineers to explore scenarios that historically took too long to evaluate. For young engineers, these skills will only become more important.

HO: What major changes or advancements have you observed in reservoir engineering and CCS over your career? What innovations are still needed?

JC: When I began my career, nearly all technical work was done manually or on mainframe systems. Reservoir simulation required batch submissions with long turnaround times. Today, simulation, uncertainty analysis, and geomechanics can be accomplished on local machines or cloud-based platforms. This democratization of computing has changed our profession.

Looking forward, CCS in particular needs several innovations that young engineers can contribute to such as

• Data assimilation and automation: CCS projects generate large volumes of multidisciplinary data. We need better workflows to integrate this information into model updates, similar to closed-loop reservoir management.
• Machine learning and analytics literacy: Not every engineer must be a data scientist, but understanding how to apply analytics—plume tracking, anomaly detection, uncertainty screening—will be a differentiator.
• Improved geomechanics integration: Pressure-boundary control and fault-stability assessments are essential. Tools exist, but simpler, more intuitive workflows are needed.
• Long-term field data: The industry lacks 20- to 30-year operating histories for CO₂ storage. As more projects progress, young engineers will play a major role in building this evidence base.

For early-career professionals, this means there has never been a better time to develop strong numerical, analytical, and interdisciplinary skills.

HO: In 2025, what are potential opportunities for new sources of CO₂ sequestration in the industry?

JC: A number of new opportunities are emerging—many of them highly relevant to young engineers entering the field.

Projects are increasingly being developed near CO₂ sources where the capture–transport–storage chain can stay below the $85/ton 45Q threshold. Examples include co-located CCS developments at ethanol facilities, chemical plants, and ammonia plants.

Recent amendments to 45Q have also renewed interest in expanding some waterfloods into CO₂ EOR projects. These types of projects offer excellent training grounds for understanding injectivity, conformance, pressure management, and surveillance—all valuable skills for CCS storage.

Another emerging trend comes from the rapid scale-up of AI data centers. Their power demands are driving proposals for new power plants paired with CCS systems. For early-career engineers, this intersection of digital infrastructure and subsurface engineering represents a promising frontier.

These trends show that CCS is not a single-pathway discipline—it touches EOR, power generation, industrial emissions, and emerging technology sectors. That diversity means more technical career pathways for younger professionals.

HO: How could long-term changes in US climate policy or market conditions impact CCS investment confidence after 2035?

JC: Predicting policy 10–15 years ahead is challenging, but young engineers should understand the forces shaping CCS.

• The US must materially reduce CO₂ and methane emissions within the next decade; otherwise, future mitigation becomes more difficult.
• Many emitters hesitate to invest in CCS because the cost is concentrated on the capture equipment.
• Plant operators may remain skeptical until more long-term storage data is available.
• The US uses incentives, while Europe uses penalties—two different business drivers.

For early-career engineers, the key message is this: regardless of policy swings, the technical foundations of CCS remain essential. Understanding pressure behavior, plume migration, PVT properties of CO₂, and geomechanics will always be required. Strong technical fundamentals will carry you through any policy environment.

HO: Looking back, what guidance would you give young engineers entering CCS or reservoir engineering?

JC: Like many people starting out, I did not know which areas I would eventually specialize in. I followed the topics that interested me—surveillance, numerical modeling, and integrated studies—and those interests shaped my career.

For young engineers, I recommend

• Build cross-disciplinary fluency.
• Seek mentorship deliberately.
• Master the fundamentals such as pressure behavior, material balance, and injection constraints.
• Develop numerical and analytics skills.
• Stay curious and challenge assumptions.

These habits create a strong foundation for any career direction you pursue.

HO: What qualities do you believe are most important for aspiring engineers, and how do you support their growth?

JC: Curiosity, humility, and disciplined thinking are essential. Engineers turn uncertain data into actionable decisions, and that requires a mindset of continuous learning.

When I mentor younger engineers, I encourage them to think deeply rather than seek quick answers. Good mentorship involves asking guiding questions and helping the mentee discover solutions through reasoning. As engineers begin solving problems independently, their confidence grows—and confidence fuels advancement.

My goal is to help the next generation see the subsurface clearly, work effectively with incomplete information, and communicate technical findings in ways that support sound operational and leadership decisions.