There’s a certain rhythm to wireline logging—a sequence of checks, measurements, and confirmations that keeps everything aligned downhole. For years, we relied on marker joints to correlate depth for plug setting, perforation services, and cased hole logging. Then came the job where that rhythm broke.
No marker joint. No fixed reference point. And no room for error.
It forced us to slow down, rethink our workflow, and implement a system that would ensure wireline well logging accuracy without our usual safety net. That job became one of the best learning experiences I’ve had in this industry—and one of the reasons our wireline courses now include protocols for zero-MJ environments.
When Marker Joints Aren’t an Option
The well was part of a pad project. The operator had chosen to omit marker joints from the casing design—standard for them, but a change for us. We were tasked with running a pump down perforating operation using a high-shot perforating gun system and setting multiple plugs. Depth correlation needed to be airtight.
In horizontal wireline, precision is everything. A 10-foot error on depth can throw off an entire perforation well stage. Missed zones. Poor frac efficiency. Wasted time. And when your crew has only one shot at getting it right, improvising isn’t an option.
We knew we had to develop a repeatable, foolproof way to correlate without an MJ. So we built one—our own way.
Building a Pseudo-Marker on the Fly
Before the first run, we reviewed the casing report. We searched for a shorter joint—something around 38 feet that could act as a pseudo-marker. Nothing. So we got creative.
Here’s what we did instead:
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Calculated the initial bump-up depth from KB and GL, verified against the collar log.
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Counted the collars carefully while running into the well.
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Stopped at ~30 degrees inclination and pulled a correlation strip through 3–4 collars.
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Logged that collar cluster to use as a reference point for all subsequent runs.
This became our makeshift marker joint.
We documented it, saved the pass, and shared the plotted log with the entire crew. From there on, every cased hole wireline operation on that well referenced this pseudo-MJ. And it worked flawlessly.
Key Procedures We Now Follow Without a Marker Joint
If you find yourself operating wireline services oil and gas jobs without a physical MJ, here’s what we’ve built into our SOPs:
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Pseudo-MJ Creation
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Pick a correlation cluster with unique collar spacing.
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Log and plot it before any guns or plugs are deployed.
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Collar Count Correlation
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Count and record each collar to the planned plug set depth.
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Match every future run to this count—not just the depth number on screen.
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Logging Curve Overlay
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Use your logging software’s correlation curve function to overlay the initial pass on all subsequent logs.
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Annotate the correlation correction clearly on each log and label the collar pattern.
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Client Confirmation
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Present the plotted correlation to the client for visual confirmation.
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Include a signature line or verbal confirmation point to solidify accountability.
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Why This Matters for the Wireline Business
The wireline services market is evolving. Operators are streamlining designs, cutting back on extras like MJs, and increasing pressure on wireline companies to adapt. If you’re offering complete wireline solutions, you need protocols that work even when the conventional tools are removed.
These pseudo-MJ workflows have now become a core part of our training. They’re taught in our wireline courses for engineers, techs, and tool specialists. Because real-world preparation beats textbook knowledge every time.
Tools and Tech That Supported the Process
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Logging cable tension monitoring helped us verify depth consistency.
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Wireline control systems were used to set alarms for pass depth proximity.
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Printed plots from cement bond logs (CBL logs) and previous production logging services were reviewed to cross-reference formations.
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Wireline pressure control equipment was double-checked due to the extended correlation process on the first run.
We also logged each run with full telemetry to validate the collar signature against future passes—just like you would in a formation evaluation or cased hole solution operation.
From Problem to Process
This job taught us something valuable: accuracy doesn’t depend on hardware alone. It depends on discipline, documentation, and real-time problem solving.
In cased hole well services, we often talk about innovation in terms of new tools—perforating systems, pipe caliper tools, hole finders, downhole cameras, and more. But sometimes, innovation is just doing something differently—and better—with the tools you already have.
Why It’s Part of Every Wireline Course I Teach
If you’re operating in wireline oilfield environments, managing a wireline unit, or running a team that provides wireline and perforating operations, you’re eventually going to run into a scenario where standard practices don’t apply.
That’s when training kicks in.
Our wireline courses now teach step-by-step processes for:
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Correlating without a marker joint
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Creating pseudo-markers
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Plotting correlation overlays
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Validating plug set depths without traditional reference points
Whether you’re in production logging, pipe recovery, or plug and abandon work, this level of adaptability separates the reliable from the reckless.
Closing Thoughts
What is wireline in oil and gas, really? It’s the art of precision under pressure. It’s controlling outcomes in unpredictable environments. And sometimes, it’s about building structure where none exists.
If you’re in the field, managing a wireline truck, deploying wireline perforating guns, or trying to build a high-performing team inside a growing wireline company, the ability to adapt to a missing marker joint isn’t just useful—it’s essential.