top of page

WillCo Drilling Intelligence - Edition 22: Rig Time Back as the Stop Leaves the Loop

Writer: William B. Contreras
William B. Contreras
5 days ago
10 min read


Four evidence folders. Field results: Gunnar AMR-WD, more than ten ranging cycles gone and roughly two weeks saved; SLB and Valeura DDS, 78 to 89 percent less survey-related rig time; SLB Retina, more than 5,300 ft of horizontal section imaged at the bit. Architecture: Baker Hughes, offset risk, live anomalies and advice in one view. Pilot and integration: Corva and Oliasoft, design to rig and back, customer pilots in preparation. Simulation: CNPC USA, about 10 percent higher average ROP; UT Austin, stick phase cut from 52.9 to 7.4 percent
Figure 1. This edition's developments, filed by the evidence behind each: field results, an architecture paper, an integration preparing customer pilots, and simulation studies. Gunnar's figures are from one US intercept, DDS from two Gulf of Thailand wells, and Retina from one North American well (WillCo analysis).

🛢️ Top Story

Gunnar Energy Services Moves Ranging Into the Drill String: More Than Ten Wireline Ranging Cycles Gone on One Intercept

Gunnar Energy Services has put active magnetic ranging inside the drill string, and on one US intercept that saved roughly two weeks of rig time, according to SPE-234404-MS, presented at APOGCE 2026 on October 14.



The authors report that conventional wireline ranging commonly takes ten to twenty drilling-interruption cycles per intercept and inflates intercept time two- to five-fold, and that across their cases ranging from inside the string improved relative placement accuracy, shortened operational time and kept well-control readiness continuous.


Directional surveys alone cannot deliver the relative accuracy an intercept demands, so the industry has relied on active magnetic ranging (AMR) run on wireline in open hole between drilling phases. Every conventional wireline ranging station means suspending drilling and tripping the BHA. Gunnar's answer is access-independent active magnetic ranging while drilling (AMR-WD). The complete ranging measurement sits in the drilling string, and the target casing is energized by current injected from the drilling well through power-class wired drill pipe or wired coiled tubing. Ranging becomes continuous, and the target well does not need to be accessible.


For legacy wells that cannot be re-entered conventionally, ask your plug-and-abandonment (P&A) contractor to price the intercept two ways, with and without wireline ranging trips, and to confirm whether the job can run power-class wired drill pipe or wired coiled tubing (WillCo analysis).


Three field histories stand behind it, from the US intercept above to an undocumented, flowing ghost well:

  • Followed a cased target for 4,684 ft, then hit the planned intercept (United States, powered drill pipe): located a cased target at 3,595 ft, followed it for 4,684 ft at a maintained 10-15 ft standoff, and intercepted at the planned 8,642 ft measured depth (MD); this is the intercept behind the KPI above.

  • Killed and abandoned the ghost well (wired coiled tubing): intercepted it at 1,068 ft MD under near-total positional uncertainty; the intercepting well built at up to 35 deg/100 ft.

  • Regulator-approved abandonment, below authorized expenditure (Western Australia, first field deployment): intercepted a legacy producer, reaching edge-to-edge contact within about eight days of drilling and ranging; the regulator approved the abandonment, and it was delivered below the authorized expenditure.


The stop disappears. Conventional wireline ranging: drill, stop drilling, trip the BHA out, rig up wireline, range in open hole, rig down wireline, trip back in, resume drilling, repeated at every ranging station; SPE general context 10 to 20 interruption cycles per intercept. Ranging while drilling: drill and range together, update relative position, steer, intercept, with no stop to range; featured US case more than ten ranging cycles gone and roughly two weeks saved
Figure 2. Conventional wireline ranging stops drilling and trips the BHA at every ranging station; ranging while drilling keeps the measurement in the drill string. The 10 to 20 cycle range is the general context Gunnar Energy Services gives in SPE-234404-MS; the ten-plus cycles and roughly two weeks are its featured US intercept.

Newer data from an ongoing US relief-well locate phase shows confident ranging detection at a 301-ft standoff; that job's intercept is the next result to watch (see What We're Watching Next).



📍 Wellbore Positioning

SLB and Valeura Energy Cut Survey-Related Rig Time 78-89% in Congested Mature Fields

SLB and Valeura Energy took the stationary survey out of most of the drilling on two Gulf of Thailand wells with Definitive Dynamic Survey (DDS), generating multiple surveys per stand without affecting drilling performance, per SPE-234490-MS, presented at APOGCE 2026 on October 14.



If your next wells thread congested mature fields, ask your directional contractor to plan survey-related rig time with continuous surveys, and to name the magnetic interference intervals where static surveys must stay (WillCo analysis).


Conventional MWD workflows rely on stationary surveys: the string stops, the tool takes a reading, drilling resumes. In congested mature fields, where new horizontal wells thread between existing and abandoned wellbores, every stop costs rig time and the gaps between stations limit how precisely the trajectory is known.


DDS instead uses continuous six-axis directional measurements and advanced survey processing to produce high-frequency definitive surveys while drilling; DDS also reduced the Ellipsoid of Uncertainty (EOU) by up to 37% versus conventional MWD surveys and raised the Separation Factor in both wells. The two wells were a shallow 3D horizontal well with high dogleg severity and continuous build-and-turn geometry, and a deep-reservoir 2D horizontal well with an extended tangent section, and the largest well-placement benefit came in the tortuous 3D profile.


The paper is precise about the boundary: through magnetic Zone of Exclusion (ZOE) intervals, conventional static surveys are still needed to maintain survey quality. That candor makes the result more useful, because it tells a planner where the stop remains (WillCo analysis).


🔬 At-Bit Measurement

SLB Retina Images Fractures Tied to Mud Losses in a North American Well

In a North American unconventional well, SLB says Retina identified natural fractures associated with mud-loss zones from at-bit images. The well's at-bit images covered more than 5,300 ft of horizontal section and also showed strata-bound fractures and thin laminations. Its October 15, 2026 feature puts the first year of commercial use at more than 50 wells across 18 locations worldwide.



If mud losses in fractured or carbonate sections drive your nonproductive time (NPT), ask your directional or logging contractor whether at-bit images can feed placement and completion decisions on the next well. Seeing those fractures at the bit, before continued drilling alters the rock, is the difference between describing losses after the fact and planning around them (WillCo analysis).


SLB also cites thin beds and sand packages later validated by wireline imaging, characterization of complex carbonate formations, and identification of fractures, vugs, stylolites, and karst structures in a Middle East well. Retina operates at temperatures up to 302°F with more than 65 hours of battery life, the two limits to check against your bottomhole temperature and planned run length (WillCo analysis).


🧠 Real-Time Architecture

Baker Hughes Framework Brings Offset-Well Risk Into the Live Drilling View

One company prepares the offset analysis, another runs pre-job modeling, and a third delivers real-time automation. That is the multi-vendor example SPE-234607-MS, presented at APOGCE 2026, uses to show how an existing gap gets worse: because automation focuses on real-time operations, offset knowledge is often not integrated into the automation workflow. Baker Hughes' framework is built to close that gap.


If three vendors touch your well, find out which one owns the offset risk list once drilling starts, and whether real-time events flow back into the offset analyses for the next well (WillCo analysis).


The payoff for the people monitoring execution is one view: the authors say presenting offset risk, real-time anomalies and advisory actions together reduces their cognitive load.


As the paper describes it, the framework does four things:

  • automatically extracts risk profiles from offset databases into a pre-drill risk assessment, and ingests the offset analyses at the start of deployment;

  • runs physics-based models of the wellbore and equipment that update continuously in real time;

  • presents offset-derived risks, detected real-time anomalies, and advisory actions in a single visualization;

  • can historize real-time events back into the offset analyses for future wells.


Baker Hughes says automating that ingestion removes the human-error risk of manually transferring offset data between applications. The authors call the contribution "a traceable, context-aware control layer." The paper is an architecture, and its value is the plumbing: offset risk arriving in the live loop as structured context (WillCo analysis).


Late-window context (Oct 12): Corva and Oliasoft announced a bidirectional integration between Oliasoft WellDesign and Corva's real-time platform, built to send design intent and limits to the rig and return as-drilled data and NPT events to design. The companies say they are preparing customer pilots.



🤖 AI Optimization

CNPC USA Links Pre-Drill and Real-Time Parameter Optimization (Simulation)

CNPC USA's SPE-234470-MS describes a closed-loop framework that carries one Bayesian optimization approach from pre-drill planning into real-time optimization; in simulation case studies under field-oriented operating conditions, the optimized solutions can increase average rate of penetration (ROP) by about 10%.


Check whether your optimization vendor's real-time model inherits the pre-drill plan's bit and parameter assumptions; the payoff of one model chain is consistency (WillCo analysis).


The authors built the method on about 17,500 records from 61 bit runs, combining ROP and bit-wear prediction with Bayesian optimization that selects the bit and drilling parameters before drilling and is extended to real-time optimization of weight on bit (WOB), rotary speed (RPM), and flow rate.


📡 On WillCo's Radar

UT Austin Models Vibration Control Inside the BHA (Simulation)



If your BHA failures trace to whirl or stick-slip, track whether this reaches a downhole prototype and field test, the next proof points to watch (WillCo analysis).


The UT Austin team models a mud-powered annular piston in the collar body that applies WOB and resistance torque close to the vibration source; in the hydro-mechanical model, its fast actuation places its operating frequency well above the characteristic frequencies of whirl, stick-slip, and bit bounce, and in simulation it restored WOB within 0.66 s after bit-bounce contact loss. The authors also report a clear limit: applying WOB did not suppress fully developed backward whirl in simulation, which will need a different strategy or mechanism.


🧭 WillCo Perspective: Taking the Stop Out of the Loop

In WillCo's reading, the drilling decision loop has long carried a stop in the middle: measure, stop, interpret, resume.


The wireline ranging run and the stationary survey exist because the information the decision needed could not be produced while the bit was turning (WillCo analysis). The field results presented at APOGCE on October 14 remove that stop from ranging and shrink it in surveying, turning position certainty from something bought with rig time into something produced while drilling (WillCo analysis). The at-bit work points to where it goes next, and the in-BHA work aims at damaging vibration at its onset (WillCo analysis).


The decision loop moves down the well, each row tagged by evidence: surface advisory (Baker Hughes, Corva and Oliasoft; architecture and pilot), surface optimization (CNPC USA; simulation), survey while drilling (SLB and Valeura Energy; field), ranging in the drill string (Gunnar Energy Services; field), at the bit (SLB Retina; field), inside the BHA (UT Austin; simulation)
Figure 3. Each row is a development in this edition, placed where it measures or acts, from surface advisory down to control inside the BHA. Color and tag mark the evidence behind it: gold for field results, blue for architecture, teal for pilots in preparation, lavender for simulation only (WillCo analysis).

Figure 3 places each development by where it measures or acts, and Figure 4 sorts them by the evidence behind each (WillCo analysis).


Evidence maturity versus direct operational leverage: Gunnar AMR-WD, SLB and Valeura DDS, and SLB Retina sit in the field and commercial band with higher leverage; the Baker Hughes framework and Corva with Oliasoft sit in the pilot and architecture band; CNPC USA and UT Austin sit in the simulation band, high potential but not yet proven in the field
Figure 4. WillCo analysis. Position reflects the evidence reported in the cited sources; it is not a formal technology-readiness certification.

The SPE The Way Ahead article "At the Bit: AI-Driven Real-Time Drilling and Geosteering" (Oct 15, 2026), from a largely Halliburton author team, supplies the counterweight with three conditions:

  • "an agent that proposes the next action and an engineer who retains the authority to accept or reject it"

  • recommendations that "operate within a management-of-change framework"

  • "a qualified engineer able to review and override each decision and a complete record of the actions taken"


They frame the future as collaborative intelligence, and their warning is concrete: in geosteering, an inaccurate state estimate can drive the wellbore out of the target, which is why the gate stays even as the stop leaves (WillCo analysis).



Taking the stop out of the loop: the old loop is measure, stop, interpret, resume; the loop moving to the bit is measure, interpret, act while drilling, with a gate between interpret and act; below the automation pathway, in its own human-authority band, the gate that does not move: agent proposes, engineer accepts or rejects, every action recorded under management of change
Figure 5. The stop leaves the loop; the engineer does not. The authority gate sits outside the automation pathway and follows the SPE The Way Ahead framing of an agent that proposes and an engineer who accepts or rejects, inside management of change (WillCo analysis).

🔭 What We're Watching Next

  • Gunnar: Will Gunnar report the intercept from the ongoing US relief-well locate phase its paper describes, and will AMR-WD move into routine P&A campaigns?

  • SLB + Valeura: Will SLB and Valeura extend DDS beyond the two reported wells, and how will they handle magnetic Zone of Exclusion intervals at scale?

  • ATCE (October 21-23): the UT Austin in-BHA actuator (SPE-234124-MS) was on the October 21 program, in the Rig Efficiency / Performance Optimization session. Its published abstract stops at simulation, so the proof point to watch is a prototype or test plan from the authors.

  • Corvacon (October 20): Corva centered this year's event on Corva 4.0. As of publication, we are watching for any public measured field result and for the first named customer pilot from the Corva and Oliasoft integration.

  • Q3 calls: what SLB (Oct 23) and Baker Hughes (release Oct 27, webcast Oct 28) put on the record about at-bit measurement, survey while drilling, or real-time advisory; we will report it in the coming editions.

  • Halliburton + INPEX: their APOGCE paper on the October 13 Technical Session 06 program (paper 234525) uses in-sub high-resolution downhole vibration data to drive RPM staging. Does it hold up as a repeatable stick-slip mitigation for Australian offshore drilling?


✅ Practical Recommendations

For operators and service companies (WillCo analysis): find the stops in your own loop and decide which ones you are ready to remove.

  • ⏱️ Count the stops: for one recent well, list every planned pause that existed only to acquire information, such as survey stations, wireline ranging runs, and logging trips, and the rig time each consumed. That list is the business case for measurement while drilling.

  • 📍 Know where the stop must stay: before adopting continuous surveying, map the intervals where it does not apply, such as magnetic interference zones that still need static surveys, so the plan carries both modes.

  • 🔗 Close the offset loop: confirm that offset-well risks reach the real-time team as structured data rather than a pre-spud slide deck, and that real-time events flow back to the next well's plan.

  • ✅ Write down the gate: for every advisory or automated recommendation, define who accepts or rejects it, how that decision is recorded, and how it is handled under management of change before the loop gets faster.


📚 References and Sources

  1. G. Rassadkin, C. Moss, F. Moss, T. Woolridge, J. Timbs, C.A. Jelly (Gunnar Energy Services). "Active Magnetic Ranging While Drilling for Relief Well Intercepts and Complex Plug and Abandonment Applications," SPE-234404-MS, SPE Asia Pacific Oil and Gas Conference and Exhibition (APOGCE 2026), presented Oct 14, 2026. DOI: 10.2118/234404-MS. https://onepetro.org/SPEAPOG/proceedings-abstract/26APOG/26APOG/D021S015R002/808532

  2. Chulakorn Yosakrai, Kritamorn Phanpanawan, Azrin Soh, A. Rakestu Prababirawa (SLB); Prairaya Somanandana, Praisont Prasertamporn, Khamawat Siritheerasas, Pattarapong Prasongtham, Siriporn Shibano (Valeura Energy). "Definitive Dynamic Survey While Drilling Reduces Collision Risk and Rig Time in Congested Mature Fields," SPE-234490-MS, APOGCE 2026, presented Oct 14, 2026. DOI: 10.2118/234490-MS. https://onepetro.org/SPEAPOG/proceedings-abstract/26APOG/26APOG/D021S015R004/808519

  3. SLB newsroom feature on Retina at-bit imaging, Oct 15, 2026. https://www.slb.com/newsroom/features/2026/2026-1015-retina

  4. P. Arevalo, K. Bone, S. Boks (Baker Hughes). "Integrating Offset Well Data and Digital Twins to Deliver Context-Aware Real-Time Drilling Advisory," SPE-234607-MS, APOGCE 2026. DOI: 10.2118/234607-MS. https://onepetro.org/SPEAPOG/proceedings-abstract/26APOG/26APOG/D011S006R001/808601

  5. "Corva and Oliasoft create a continuous learning loop between well design and drilling" - Oliasoft, Oct 12, 2026. https://oliasoft.com/articles/corva-and-oliasoft-create-a-continuous-learning-loop-between-well-design-and-drilling

  6. Jiaqing Yu, Yangjun (Kevin) Liu, Jason Sheng, Weihong Gao, Yongliang You, Chris Cheng, Haige Wang, Yu Jiang, Lance Endres (Yu, Liu, Cheng and Wang: CNPC USA, Houston). "Intelligent Pre-Drill and Real-Time Optimization of Drilling Parameters," SPE-234470-MS, APOGCE 2026. DOI: 10.2118/234470-MS. https://onepetro.org/SPEAPOG/proceedings-abstract/26APOG/26APOG/D012S001R001/808554

  7. Myung Sun Park, Yifan Zhang, Pradeepkumar Ashok, Dongmei Chen, Eric van Oort (The University of Texas at Austin). "Real-Time Drillstring Vibration Mitigation Using an Automated Downhole Actuator," SPE-234124-MS, SPE Annual Technical Conference and Exhibition (ATCE 2026), presentation Oct 21, 2026. DOI: 10.2118/234124-MS. https://onepetro.org/SPEATCE/proceedings-abstract/26ATCE/26ATCE/D011S005R005/808963

  8. Ashish Fatnani, Shashwat Verma, Yusuf Ajibola Falola, Vivekvardhan Reddy Kesireddy, Aman Srivastava, Geetha Gopakumar Nair. "At the Bit: AI-Driven Real-Time Drilling and Geosteering" - SPE The Way Ahead (JPT), Oct 15, 2026. https://jpt.spe.org/twa/at-the-bit-ai-driven-real-time-drilling-and-geosteering

  9. APOGCE 2026 technical programme, Technical Session 06 (Drilling Technologies) and Technical Session 15 (Directional Drilling). https://www.spe-events.org/apogce2026/technical-programme/technical-session-06-drilling-technologies and https://www.spe-events.org/apogce2026/technical-programme/technical-session-15-directional-drilling

  10. ATCE 2026 technical program, Rig Efficiency / Performance Optimization. https://www.atce.org/2026-technical-program-1/rig-efficiency-/-performance-optimization

  11. Corvacon: Nexus, Oct 20, 2026 - https://www.corvacon.ai/

  12. "SLB Announces Date for Third-Quarter 2026 Results Conference Call" - SLB, Sep 28, 2026. https://www.slb.com/newsroom/press-release/2026/pr-2026-0928-q3-earnings-call-announcement

  13. "Baker Hughes Announces Dates for Third-quarter Earnings Release and Webcast" - Baker Hughes, Sep 28, 2026. https://investors.bakerhughes.com/news/press-releases/news-details/2026/Baker-Hughes-Announces-Dates-for-Third-quarter-Earnings-Release-and-Webcast/default.aspx

  14. Prior WillCo Drilling Intelligence editions and archive - https://willcodrilling.com/blog


About this report: The WillCo Drilling Intelligence Report is a weekly synthesis of verified developments in digital drilling and well construction, published by WillCo Drilling Consulting. Analysis, forecasts, and recommendations reflect WillCo's independent engineering perspective.



📖 Glossary of Acronyms



Comments

bottom of page