作者：Patrick Hayes，Tracerco

过去二十年来，钻井和完井技术飞速发展，使作业者能够更精准地开采日益复杂的油藏。然而，尽管作业执行变得更加精细，但该行业仍然面临着一个根本性的挑战：如何准确衡量钻井和完井决策是否达到了预期效果。

传统上，成功与否取决于产量或累计采收率等高层次经济指标。虽然这些指标很有用，但它们对油井沿其长度方向的运行情况、哪些完井阶段发挥了作用，以及井位部署决策是否达到了预期目标等方面的洞察有限。因此，执行效率仍然存在不确定性，尤其是在水平井和多级完井方面。

降低这种不确定性需要采用能够提供定量、特定阶段井性能信息的诊断方法。化学示踪技术正是这样一种工具，它使作业者能够直接测量井段或井层段的贡献、清井效率和流体运移情况。这为未来的井位布置和完井设计决策提供了宝贵的反馈。

诊断差距

随着油井长度增加和完井工艺日益复杂，传统的诊断工具已难以跟上步伐。测井数据、压力数据和地面产量测量结果可以表明油井正在产油，但它们很少能对以下问题给出明确的答案：

• 井筒的哪些部分正在产生渗漏？
• 水流沿侧向分布是否均匀？
• 是否存在某些环节表现不佳或被省略的情况？
• 完井液的回收效率如何？

在非常规油气开发中，由于钻井和完井设计在不同井场之间重复使用，无法量化执行结果可能导致未经验证的设计假设被反复沿用。随着时间的推移，这会加剧不确定性，并增加井位选择或完井设计方案欠佳的风险。

目前通常缺少的是一种能够在稳定条件下运行，并在不中断作业的情况下区分油、气和水成分的直接测量技术。

定量诊断工具

化学示踪剂技术通过将独特的化学标识符嵌入完井液或材料中，为弥补这一差距提供了一种途径。这些示踪剂一旦部署，就会被带回地面进行分析，从而使作业者能够以精细的粒度量化其贡献和行为。

与间接诊断方法不同，示踪剂诊断方法提供的是实测数据而非推断结果。相态示踪剂能够区分烃类和水，而段态示踪剂则使作业者能够评估井筒内各个完井段的情况。

化学示踪剂的一项关键优势在于其能够在稳定生产期间发挥作用，无需停井或进行侵入性干预。这使得诊断工作能够在不中断钻井或完井计划的情况下进行。

将示踪剂应用于井位验证

井位选择是影响油井产能的最关键因素之一。然而，仅凭常规数据很难验证水平井相对于储层质量、断层或天然裂缝的位置是否最优。

示踪剂诊断技术使作业者能够量化沿井筒长度方向的流入量，从而揭示可能表明井位问题的变化。例如，井底或井脚段流入量不成比例地偏高，可能凸显储层接触不均匀或完井效果不佳。

在与断层或地层边界相交的井中，示踪剂数据可以提供不同层段间流体运动的证据，从而深入了解储层连通性，并有助于验证规划阶段使用的地质模型。通过将这些定量信息反馈到地下作业和钻井流程中，作业者可以优化后续井的着陆区选择和水平井位布置。这可以降低成本并提高钻井效率。

评估完工设计有效性

除了布置位置外，化学示踪剂越来越多地用于评估完井设计在各阶段的性能。在多级水平井中，示踪剂数据可以识别出贡献过大（或完全没有贡献）的阶段，从而突出增产效果、井组效率或机械隔离方面的潜在问题。这些信息在评估新的完井设计或材料时尤为重要。通过比较各阶段的示踪剂贡献，作业者可以确定井距、流体用量或处理技术的改变是否能带来一致的效果。

示踪剂诊断还可以用于评估裂缝驱动的相互作用，帮助识别可能影响完井效果的阶段或相邻井之间的连通性。

测量完井液清理效率

完井液回收对油井产能和完整性至关重要，但其清理效率通常难以直接量化。残留流体可能降低产能或掩盖完井作业的真实效果。

通过在完井液中添加特定示踪剂，作业者可以测量完井液回收率和回收程度随时间的变化。这使得作业者能够逐级评估清井效率，从而深入了解完井设计是否有利于有效清除流体。

量化清理性能使操作人员能够改进流体选择、泵送策略和回流程序，从而在大规模应用设计之前减少不确定性。

重要的是，这种方法侧重于执行效率，而不是下游生产结果，与钻井和完井决策密切相关。

通过稳态诊断降低不确定性

化学示踪剂方法的显著优势在于其在稳态条件下的适用性，包括采用人工举升的油井。这使得诊断工作能够在不改变运行参数或引入额外运行风险的情况下进行。

通过提供连续的、特定阶段的洞察，示踪剂数据可以支持对早期生命阶段完井行为和油井完整性的持续评估——这是设计经验最有价值的时期。

这种稳态能力使示踪剂诊断区别于许多传统工具，并支持以数据驱动的方式改进钻井和完井实践。

对钻井和完井决策的影响

随着钻井项目规模扩大，涉及多个油井和油田，验证假设的能力变得日益重要。化学示踪诊断提供了一个反馈回路，将执行决策与可衡量的结果联系起来。

通过将示踪剂提供的信息融入钻井和完井工作流程，作业者可以：

• 提高对田间开发策略的信心；
• 根据实测性能改进完井设计；
• 及早发现执行效率低下的问题；
• 在进行大规模复制之前，先降低不确定性。

示踪技术并非取代现有的诊断方法，而是通过提供井下作业的定量确认来补充传统工具。

在油井结构日益复杂、容错空间不断缩小的环境下，降低井下不确定性至关重要。化学示踪剂提供了一种实用且定量的方法来评估井位布置和完井设计的有效性，从而提供有助于做出更明智钻井和完井决策的信息。

通过侧重于测量而非推断，示踪剂诊断有助于缩小设计意图与实际执行情况之间的差距，使运营商在优化未来油井时更有信心。

By Patrick Hayes, Tracerco

Drilling and completion technologies have advanced rapidly over the past two decades, enabling operators to access increasingly complex reservoirs with greater precision. However, while execution has become more sophisticated, the industry still faces a fundamental challenge: accurately measuring whether drilling and completion decisions have delivered the intended results.

Traditionally, success is inferred from high-level economic indicators such as production rates or cumulative recovery. While useful, these metrics offer limited insight into how a well is performing along its length, which completion stages are contributing, or whether well placement decisions achieved their design intent. As a result, uncertainty remains around execution efficiency, particularly in horizontal wells and multistage completions.

Reducing this uncertainty requires diagnostic approaches that can provide quantitative, phase-specific well performance insights. Chemical tracer technologies have emerged as one such tool, enabling operators to directly measure contribution, cleanup efficiency and fluid movement at the stage or interval level. This provides valuable feedback for future well placement and completion design decisions.

The diagnostic gap

As wells have become longer and completions more complex, traditional diagnostic tools have struggled to keep pace. Logs, pressure data and surface production measurements can indicate that a well is flowing, but they rarely provide definitive answers to questions such as:

• Which sections of the wellbore are contributing?
• Is flow evenly distributed along the lateral?
• Are certain stages underperforming or bypassed?
• How effectively has completion fluid been recovered?

In unconventional developments, where drilling and completion designs are replicated across pads, the inability to quantify execution outcomes can lead to repeated design assumptions being carried forward without validation. Over time, this compounds uncertainty and increases the risk of sub-optimal well placement or completion design choices.

What is often missing is a direct measurement technique that can operate under steady-state conditions and distinguish among oil, gas and water contributions without disrupting operations.

Quantitative diagnostic tool

Chemical tracer technology offers a means of addressing this gap by embedding unique chemical identifiers within completions fluids or materials. Once deployed, these tracers are produced back to surface and analyzed, enabling operators to quantify contribution and behavior at a granular level.

Unlike indirect diagnostics, tracer-based methods provide measured data rather than inferred results. Phase-specific tracers allow differentiation between hydrocarbons and water, while stage-specific tracers enable operators to assess individual completion segments along the wellbore.

One key advantage of chemical tracers is their ability to function during steady-state production, eliminating the need for well shut-ins or intrusive interventions. This allows diagnostics to be conducted without interrupting drilling or completion schedules.

Applying tracers to well placement validation

Well placement decisions are among the most critical factors influencing well performance. However, validating whether a lateral has been optimally positioned relative to reservoir quality, faults or natural fractures can be challenging using conventional data alone.

Tracer diagnostics enable operators to quantify contribution along the length of the wellbore, revealing variations in inflow that may indicate placement issues. For example, disproportionate contribution from heel or toe sections can highlight uneven reservoir contact or completion effectiveness.

In wells intersecting faults or stratigraphic boundaries, tracer data can provide evidence of fluid movement between compartments, offering insight into reservoir connectivity and helping validate geological models used during the planning phase. By feeding this quantitative information back into subsurface and drilling workflows, operators can refine landing zone selection and lateral placement in subsequent wells. This can reduce costs and build efficiencies into drilling.

Evaluating completion design effectiveness

Beyond placement, chemical tracers are increasingly used to assess completion design performance at the stage level. In multi-stage horizontal wells, tracer data can identify stages that contribute disproportionately — or not at all — highlighting potential issues with stimulation effectiveness, cluster efficiency or mechanical isolation. This information is particularly valuable when evaluating new completion designs or materials. By comparing tracer-derived contribution across stages, operators can determine whether changes in spacing, fluid volumes or treatment techniques are delivering consistent results.

Tracer-based diagnostics can also be applied to evaluate fracture-driven interactions, helping identify communication between stages or adjacent wells that may influence completion effectiveness.

Measuring completion fluid cleanup efficiency

Completion fluid recovery plays a critical role in well performance and integrity, yet cleanup efficiency is often difficult to quantify directly. Residual fluids can impair flow capacity or mask the true effectiveness of the completion.

By tagging completion fluids with specific tracers, operators can measure the rate and extent of fluid recovery over time. This enables assessment of cleanup efficiency on a per-stage basis, providing insight into whether completion designs facilitate effective fluid removal.

Quantifying cleanup performance allows operators to refine fluid selection, pumping strategies and flowback procedures, reducing uncertainty before applying designs at scale.

Importantly, this approach focuses on execution efficiency, rather than downstream production outcomes, aligning closely with drilling and completion decision making.

Reducing uncertainty through steady-state diagnostics

A notable advantage of chemical tracer methods is their applicability under steady-state conditions, including wells operating with artificial lift. This allows diagnostics to be conducted without altering operating parameters or introducing additional operational risk.

By providing continuous, phase-specific insight, tracer data can support ongoing evaluation of completion behavior and well integrity during early life — a period when design learnings are most valuable.

This steady-state capability distinguishes tracer diagnostics from many traditional tools and supports data-driven refinement of drilling and completion practices.

Implications for drilling and completion decision making

As drilling programs scale across multiple wells and fields, the ability to validate assumptions becomes increasingly important. Chemical tracer diagnostics offer a feedback loop that connects execution decisions with measurable outcomes.

By incorporating tracer-derived insights into drilling and completion workflows, operators can:

• Improve confidence in field development strategies;
• Refine completion designs based on measured performance;
• Identify execution inefficiencies early;
• Reduce uncertainty before replication at scale.

Rather than replace existing diagnostics, tracer technologies complement traditional tools by providing quantitative confirmation of what has been executed downhole.

In an environment where wells are becoming more complex and margins for error continue to narrow, reducing downhole uncertainty is critical. Chemical tracers provide a practical, quantitative means of evaluating well placement and completion design effectiveness, delivering insights that support better-informed drilling and completion decisions.

By focusing on measurement rather than inference, tracer diagnostics help close the gap between design intent and execution reality, enabling operators to move forward with greater confidence as they optimize future wells. DC