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Everything is Broken: Broken hands on broken ploughs, broken treaties, broken vows, broken pipes, broken tools, people bending broken rules…(Bob Dylan). In the spirit of global discordance, let’s look at failed #welltests… Sometimes mysterious, unusual, and bizarre things happen

Looking to Expand your Repertoire? Impulse testing is done without flowing. Impulse tests are used very early in the life of a well, before any flow. Pressure recorders can be run at surface or downhole to the sandface.

Everything is Broken: Broken hands on broken ploughs, broken treaties, broken vows, broken pipes, broken tools, people bending broken rules…(Bob Dylan). In the spirit of global discordance, let’s look at weird #welltests… Sometimes mysterious, unusual, and bizarre things happen

Everything is Broken: Broken hands on broken ploughs, broken treaties, broken vows, broken pipes, broken tools, people bending broken rules…(Bob Dylan). In the spirit of global discordance, let’s look at failed #welltests… Sometimes mysterious, unusual, and bizarre things happen

Want an Edge on the Competition? Thermal data provide vital welltest diagnostics. Subsurface pressure recorder data includes corresponding sensor temperature data, a vital but underused resource for diagnostics.

Welltest 105: Thermal focuses on observations and diagnostics

More than Just PTA… Temperature validation and differentials help with qualitative assessment and adds value. This example displays liquid influx and wellbore hydrodynamics throughout both flow and buildup periods. Thermal diagnostics have saved economic wells by illustrating unexpected liquid

More than Just PTA… While PID and PIDD tests have their place as stand-alone assessment tools, this example of added value wasn’t planned that way! To shorten a long, complicated story, two zones were perforated before installing an isolation

New to Gas Field Operations? Surface pressure data are a valuable resource. Surface pressure recorders are deployed by the same team that runs Acoustic Well Sounders, often in conjunction. Surface data recorders can also have channels for Production Testing,

More than Just PTA… Checking differentials provides added value. The operator was ready to walk away from this well due to uneconomically low gas rates. However, note the huge tubing/casing differential, not to mention the casing pressure trend shift

More than Just PTA… Checking differentials provides added value. Note this case where an unusual reversal was exhibited by the tubing/casing differential after flowing the well. This suggested there may have been an air column trapped in the annulus.

New to Oil Field Operations? Acoustic Well Sounders (AWS) help estimate bottomhole pressures in pumping wells. Acoustic well sounders and surface pressure recorders are installed, operated, and maintained by surface data crews, often in conjunction.  

PTA is an Exploration tool when we conduct a drill stem test (DST). DST’s are one of the first tests we can run, while drilling, thus in the open hole environment. DST’s are simple closed chamber impulse tests, dual

PTA is a Management tool for decision tree analysis. PTA is an invaluable piece of the complex hydrocarbon recovery puzzle, where everything is measured indirectly and interpreted by a team of specialists. Corroborating with seismic, core, logs, cross-sections, maps,

New to petroleum Welltesting? Production Testing services clean up and flow test wells.  Production testing teams operate a range of equipment from simple one-man flow provers to complicated four-stage separation and multi-phase metering manned 24/7 by tandem crews.

PTA is an Evaluation tool when we forecast hypothetical cases to probe and ascertain project viability. Theoretical, what-if, scenarios can be generated to evaluate economics and feasibility of proposed projects. For example, completing a PTA once, management wondered what-if

PTA is a Marketing tool when we generate theoretical test designs for financial sales presentations. Externally for attracting capital investment, or internally for budget proposals. Hypothetical, what-if, scenarios can easily be generated, complete with productivity forecasts into the future.

New to the term Wireline? Wireline services run welltest pressure instruments. Slickline operators, equipment, tools, and instruments are intrinsic to petroleum welltesting.

Welltest 101: Wireline focuses on topics related to wireline (slickline) deployment of subsurface pressure

PTA is a Geological tool when we test CBM desorption properties. Coalbed Methane (CBM) is a Biogenic gas, very high C1 content, clean burning, plentiful here in Alberta, Canada, perfect for heating homes, stores, barns, workshops, and greenhouses from

PTA is a Reserves tool when we analyze gas material balance. Of course, MBA requires at least two satisfactory test results and quality production accounting. Maybe two tests are okay for a single well, but in a pool with

Did you know that Mini-Frac’ or Diagnostic Fracture Injection Tests (DFIT) can “Double For Initial Tests” in Alberta if subsurface pressure recorders are installed long enough. Formation leak-off data can be extrapolated to a p* acceptable for AER Initial

PTA is a Reserves tool when we model reservoir boundaries. Analysts often assume a single drilling spacing unit (DSU) for external boundaries and, thus, volumetric reserves. This is an acceptable standard for initial tests, which are usually (hopefully) infinite

PTA is a Geological tool when we ascertain rock mechanics. Diagnostic Fracture Injection Tests (DFIT), Mini-Frac’ tests, and Step-Rate tests all evaluate hydraulic rock-stress properties. G-Function analysis quantifies break-over pressure, frac’ closure pressure, closure dynamics, and frac’ gradient. Known

Did you know that Alberta gas wells with deliverability over 300 e3m3/d require multi-rate or isochronal flow tests? Moreover, but little known, is that: if you didn’t do a multi-rate test, but did do a pressure build-up test, and

PTA is a Geological tool when we infer hydrocarbon limits. Pressure derivative pattern or trend changes include several characteristics which infer hydrocarbon deposit boundaries or limits. External no-flow boundaries like faults and channel widths are identifiable. High flow conglomerate

PTA is an Economics tool when we produce deliverability forecasts. Well test rates (initial) are not the same as steady-state flow rates in the future. Flow rates usually exhibit a decline curve. Given a good synthetic model pressure build-up

Did you know there are several alternate or unconventional welltesting methods for achieving AER Initial Pressure requirements? Perforation inflow or injection tests, fracture injection or fall-off, and formation leak-off tests are some examples. Just a little known TechTip…

PTA is an Exploitation tool when we draw isobaric pressure maps. Maps are a pool tool — you must have several wells in the same formation, with appropriate tests, and qualified PTA data, to draw maps. Notwithstanding, good maps

PTA is an Exploitation tool when we evaluate under-performing assets. Making the most of what you have is astute business practice, especially during times of low commodity prices and market volatility. Operations should always be on the lookout for

Did you know Pressure Transient Analysis (PTA) can extrapolate a reservoir pressure (p*) to satisfy AER Initial Pressure requirements? You don’t have to conform with the “2 kPa Rule.” Engineering can move your completion operations along faster and more

PTA is a Completions and Workover tool when we test for skin — near wellbore damage. Oil well productivity (IPR), gas well deliverability (AOF), and water well injectivity, are all a function of flowing conditions between the rock matrix

PTA is a Production Engineering tool when we investigate pump performance. Pump performance is directly related to sandface inflow (AOF, LIT, IPR). Bottomhole tests are therefore recommended, but running pressure recorders below a sucker rod or screw pump, or

Did you know that AER Annual well testing requirements can often be satisfied from surface? Acoustic Well Sounders (AWS) are common in oil fields, and surface pressure recorders are acceptable in dry gas pools. Just a little TechTip hint…

PTA is a Production Engineering tool when we draw tubing performance curves. Liquid lift is a factor we must contend with in most natural gas wells. Recovering (lifting) liquids with the gas is a velocity issue, and velocity is

PTA is a Production Engineering tool when we produce inflow relationships: AOF, LIT, and IPR curves for production operations. Gas Absolute Open Flow (AOF) curves help size separation and compression facilities and set wellhead operating pressures. Laminar-Inertial-Turbulence (LIT) curves

With regards to AER Initial Pressure requirements, did you know that subsurface pressure recorder data can be submitted without the extrapolated pressure (p*) from Pressure Transient Analysis (PTA), if data meet the 2 kPa Rule? Economic strategy if completion

PTA is a Reservoir Engineering tool when we infer liquid contacts from pressure derivative buildup pattern deflections. Remember, analytical equations solve for transmissivity (kh/µ); net pay (h) and viscosity (µ) are assumed to be constant to derive perm’ (k).

PTA is a Reservoir Engineering tool when we detect fluid volatility. Free gas caps, solution gas, volatile oil, and retrograde condensate gas all leave signature pressure buildup response patterns. Shut-in pressure humps may indicate phase redistribution, gas going back

Welltest Engineering is idiosyncratic: words are different, acronyms are strange, expectations are high, accuracy and precision are standard protocols. All staff in the responsibility chain need an awareness of equipment, tools, and operations. Practical knowledge about quality control, data

PTA is a Reservoir Engineering tool when we identify interference or communication or isobaric pressure boundaries. Interference can occur while frac’ing up-hole zones or nearby wells in dense drill spacing units (DSU). Communication due to production of offset wells

PTA is a Reservoir Engineering tool when we infer drive mechanics. Gas caps reveal themselves in the pressure buildup because of a dramatic change in reservoir fluid viscosity (µ) — the gas/water interface manifests as a deviation in derivative

So are we… Re-branding with a fresh new website to publicize our Technical Coaching employee training and development material. Well testing is about measuring and recording flow rate and pressure data. Talented and experienced wellsite equipment operators are always

PTA is a Reservoir Engineering tool when we qualify induced fracture (frac’) effectiveness. Successful fracture stimulation treatments generate an Infinite Conductivity pattern, identified by a long Linear half (½) slope dominating the pressure build-up. Less effective treatments generate a

PTA is a Reservoir Engineering tool when we differentiate dual porosity or, more particularly, natural fracture vs. matrix deliverability. Natural fractures derive from tectonic events: folding and faulting. Permeability in natural fractures is orders-of-magnitude higher than in porous rock

So are we… Re-branding with a fresh new website to publicize our Technical Coaching employee training and development material. Corporate directors, managers, and stakeholders depend on realistic, practical, advice from testing wells. Petroleum Reservoir and Production Engineering teams initiate

PTA is a Reservoir Engineering tool when we derive insitu permeability to oil, gas, or water. Remember, PTA analytical equations solve not for permeability (k), but transmissivity (kh/µ); net pay (h) and viscosity (µ) are assumed to be constant

PTA is a Reservoir Engineering tool when we identify reservoir flow regimes. Flow regime development, or lack thereof (obscured, absent, transient), is crucial to analytical confidence levels. Vertical Radial flow was the norm fifty years ago: easy discovery, conventional,

So are we… Re-branding with a fresh new website to publicize our Technical Coaching employee training and development material. Technical Coaching is for anybody new to a welltest workspace: wellsite data acquisition, field-office data processing, or engineering data analysis.

Welltesting & Pressure Transient Analysis (PTA) are Vital Tools for Upstream Oil & Gas Strategy. Welltesting and PTA are disciplines of Reservoir and Production Engineering. Reservoir engineering because: we identify insitu flow regimes, interpret matrix and fracture flow characteristics,

Everything is Broken (including our web site): Broken hands on broken ploughs, broken treaties, broken vows, broken pipes, broken tools, people bending broken rules…(Bob Dylan). In the spirit of global disorder, let’s look at failed #welltests… Sometimes mysterious, unusual,

Everything is Broken (including our web site): Broken hands on broken ploughs, broken treaties, broken vows, broken pipes, broken tools, people bending broken rules…(Bob Dylan). In the spirit of global disorder, let’s look at failed #welltests… Sometimes mysterious, unusual,

Everything is Broken (including our web site): Broken hands on broken ploughs, broken treaties, broken vows, broken pipes, broken tools, people bending broken rules…(Bob Dylan). In the spirit of global disorder, let’s look at weird #welltests… Sometimes mysterious, unusual,

Everything is Broken (including our web site): Broken hands on broken ploughs, broken treaties, broken vows, broken pipes, broken tools, people bending broken rules…(Bob Dylan). In the spirit of global disorder, let’s look at failed #welltests… Sometimes mysterious, unusual,

Working from home is one thing, working from anywhere takes some special gear, know-how, and patience. You should know how to tether your laptop to your mobile phone, to create a Wi-Fi connection, on the road, for RUSH situations.

Regulatory requirements are those rules that an operator has a legal obligation to meet and against which the #AER may take enforcement action in cases of non-compliance. The AER issues weekly Initial and Annual Outstanding requirements. Extensions to deadlines

Working from home is one thing, working from anywhere takes some special gear, know-how, and patience. We’re on the road enough that we cancelled our land line in favour of a VoIP Internet Phone Service. No change to our

The manner in which #welltests are conducted and reported is always critical to the value of data obtained. Directive 40 (D40) defines the #AER quality standards required for well tests to fulfill survey requirements.

Annual

The manner in which #welltests are conducted and reported is always critical to the value of data obtained. Directive 40 (D40) defines the #AER quality standards required for well tests to fulfill survey requirements.

Stabilized

Working from home is one thing, working from anywhere takes some special gear, know-how, and patience. One of our must-have road warrior tools to keep us lean, light, and productive while travelling, is a USB Monitor. These portable 14

Well test information is critical for the prudent management of oil and gas reservoirs. Well testing is thus an integral part of the overall production and depletion strategy of a reservoir. The Alberta Energy Regulator (#AER) defines the minimum

Well test information is critical for the prudent management of oil and gas reservoirs. Well testing is thus an integral part of the overall production and depletion strategy of a reservoir. The Alberta Energy Regulator (#AER) defines the minimum

Working from home is one thing, working from anywhere takes some special gear, know-how, and patience. Road warriors know there are plenty of opportunities for problems, sometimes things just don’t work as advertised. Internet, and therefore cloud services, aren’t

Well test information is critical for the prudent management of oil and
gas reservoirs. Well testing is thus an integral part of the overall production
and depletion strategy of a reservoir. The Alberta Energy Regulator (#AER) defines
the minimum

Well test information is critical for the prudent management of oil and
gas reservoirs. Well testing is thus an integral part of the overall production
and depletion strategy of a reservoir. The Alberta Energy Regulator (#AER) defines
the minimum

Working from home is one thing, working from anywhere takes some special gear, know-how, and patience. Road warriors need to know the particular plug types and voltages to accommodate their electronic devices. Most devices charge off transformers, so either

Heading into a roller-coaster of a break-up, both Oil and Gas (#LNG) wells, coming on-stream in March, were up 40% over last year. Torxen has lead Oil wells steadily for seven months, while Peyto takes over Gas from 7G

Regulations pertinent to Alberta well testing are contained in the Oil and Gas Conservation  Regulations. Section 11.102 authorizes #AER Directive 40 (D40) to set well test requirements and standard procedures, as well as compliance and enforcement protocols.

Coalbed Methane is a Biogenic #Gas, extremely high C1, plentiful here in Alberta, perfect for heating homes, stores, shops, and sports facilities on our clean natural gas grid. Eventually maybe even #LNG cruise and container ships. Coalbed (#CBM) developments

Working from home is one thing, working from anywhere takes some special gear, know-how, and patience. Don’t open your mobile bill to an April Fool’s Joke: roaming and mobile data costs can be significant working on the road. Not

Coalbed Methane is a Biogenic #Gas, extremely high C1, plentiful here in Alberta, perfect for heating homes, markets, churches, and schools on our clean natural gas grid. Eventually maybe even #LNG ferries and trains. Coalbed (#CBM) developments all require

Coalbed Methane is a Biogenic #Gas, extremely high C1, plentiful here in Alberta, perfect for heating homes, ranches, greenhouses, and community centres on our clean natural gas grid. Eventually maybe even #LNG buses and trucks. Coalbed developments all require

Working from home is one thing, working from anywhere takes some special gear, know-how, and patience. On the road low quality sporadic bandwidth can be very frustrating. When even Radio Paradise starts breaking up while streaming, and you just

Coalbed Methane is a Biogenic #Gas, extremely high C1, plentiful here in Alberta, perfect for heating homes, farms, greenhouses, and businesses on our clean natural gas grid. Eventually maybe even #LNG exports. Coalbed developments all require at least one

Planning a Section 4.3 application for Underground Gas Storage? Maximum bottomhole injection pressure and maximum average reservoir pressure data are required to define the upper limit to the operating pressures of the scheme (i.e. maximum wellhead injection pressure). A

Oil and Gas (#LNG) wells coming on stream last month were down 14% and 9%, year/year, respectively. Activity is still very weak, and that was before the price war broke out. If the Saudis and Russians are trying to

Planning a Section 4.2 application for Acid Gas Disposal? Bottomhole injection pressure, maximum sandface (reservoir) pressure, caprock threshold pressure, fracture propagation pressure, and formation fracture pressure estimates are all required. It is not desirable for acid gas disposal wells

Planning a Water Disposal well application? Disposal refers to the injection of fluids for purposes other than enhanced recovery or gas storage. It is not desirable for water disposal wells to exceed the formation fracture pressure because of possible

Planning to Self Declare Commingled Production? Does the reservoir pressure, in any of the pools or intervals proposed for commingling, exceed 90% of the lesser of the closure pressure or breakdown fracture pressure of any of the other pools

Planning to convert or drill wells for water injection or effluent disposal? You might want to consider an injectivity #welltest before designing surface equipment. I usually recommend a 24 h constant rate test followed by a 96 h pressure

Planning to convert or drill wells for water injection or effluent disposal? #AER Directive 51 (D51), Section 8.1, outlines initial #welltest requirements for either: 1) Step-Rate Injectivity test, 2) an In-Situ Stress test, or 3) a Mini Frac’ test

The most common data inconsistency leading to Alberta #welltest compliance issues is a miss-match between the Gross Completion Interval (GCI) filed in Petrinex, and the measured depth interval (TTOPL.M & TBASL.M) submitted in a PAS file. Even though horizontal

Regulations pertinent to #welltesting are contained in the Alberta Oil and Gas Conservation Regulations. Section 11.102 provides the authority to set requirements for well testing within this directive. Sections 11.005 and 11.120 require that all tests be submitted. Enforcement

Impulse Tests are Useful for many Other Applications. Surface casing-vent tests can be conducted using the closed-chamber method. Closed-chamber drill stem tests. Pre-frac’ evaluations and frac’ falloff tests. Alberta AER Initial Pressure requirements can be achieved with a variety

Exploitation Correlations. Exploitation correlation plots can be developed for specific fields and pools. Enough tests and end-results need to be monitored so correlations can be observed. Eventually these plots are used for making on-site real-time tie-in or fracture treatment

Oil wells coming on stream in January fell from December, and were slightly lower than last year. Gas wells coming on stream were also down from last month, but ahead of last year. Yee Haw! Torxen led in oil

Proving Movable Reserves. In this example a high permeability sandstone overlaid a shale zone. Decline curve analysis indicated natural gas (#LNG) reserves greater than volumetrics could justify. It was hypothesized that the shale gas reserves migrated vertically, due to

Perforation Inflow Distribution Diagnostic (PIDD) Tests. The PID #welltest is analogous to production logging when two or more intervals are perforated. Based on changes to the Dp/Dt slope, gas (#LNG) inflow and AOF ratios can be estimated. Starting with

Perforation Inflow Distribution Diagnostic (PIDD) Tests. The PID #welltest is analogous to production logging when two or more intervals are perforated. Based on changes to the Dp/Dt slope, gas (#LNG) inflow and AOF ratios can be estimated. Starting with

Perforation Inflow Diagnostic (PID) Tests—Modern Analysis. Colleague Florin Hategan suggests that formation net pay (h) be replaced by effective perforated pay (hp) thus generating formation permeability (kf) such that formation flow capacity becomes (kh = kf — h) (unpublished).

Perforation Inflow Diagnostic (PID) Tests—Modern Analysis. Modern analytical techniques to estimate order-of-magnitude reservoir flow characteristics (kh, s, q, p*) have been programmed into IHS WellTest™ software. Slug, PITA, or Closed Chamber diagnostics can be performed for either build-up or

Perforation Inflow Diagnostic (PID) Tests—Conventional Analysis. Using conventional #welltest analysis software, then, data before the critical flow cut-off can be analyzed as a pressure drawdown. Data following the cut-off point can be analyzed as a pressure buildup. Conventional pressure

Perforation Inflow Diagnostic (PID) Tests—Conventional Analysis. For this test, a surface #welltest data recorder was rigged in, the well was perforated, and the resulting pressure buildup was recorded. As per accepted closed-chamber #DST theory, gas inflow rates were calculated

Surface Data Recorders Modernize Underutilized Techniques. Impulse testing has been around for some time and analytical theory is well documented. Modern electronic surface data acquisition equipment has made impulse testing practical and economic in the Western Canada Sedimentary

Finally, Welltest Specialists believes #welltest analysis (#PTA) software should be upgraded to utilize the available temperature data for calculation of pseudo-pressure and pseudo-time variables. This should not pose a significant problem to programming code. Since thermal data are already

N2 p/T inversion curves

Wet #gas (#LNG) temperature sensors (as in production logging) could easily be added to modern electronic pressure recorder designs. As the use of temperature data increases for welltest diagnostics, limitations of

New oil wells coming on steam post the strongest month in over a year, while new gas wells (#LNG) continue a steady upward trend for the winter. Torxen and 7G continue the steady lead they have held for several

Thermal Storage – Pressure Derivative

Thermal Data Helpful for Identifying Valid Radial Flow Conditions. Temperature data recorded during a #welltest can be reflective of wellbore storage or afterflow effects and can help identify valid radial flow

Complex Derivative Behaviour = Heterogeneous System

Thermal Interference Demonstrated Beyond 50 m Radius. Such extensive alteration of reservoir temperatures suggests that a considerably long time might be required for the formation to return to insitu thermal

Joule-Thompson (JT) Cooling – Observation Well

Thermal Interference Demonstrated Beyond 50 m Radius.

A common assumption is that temperature changes around a wellbore do not penetrate deep into the formation during a

Thermal Derivative

One overlooked characteristic of thermal #welltest data is the interpretation of lithology changes. The temperature buildup, as temperatures return to insitu conditions, is a function of lithology conductivity, which differs for #gas filled pores

Still Low Year/Year

New wells coming on stream are rebounding after the summer season, but are down compared to a year ago. Gas (#LNG) was split between 7G and Tourmaline, while oil was dominated again by

Thermal Storage = Non Radial Flow

Thermal Data Trends are Useful for Welltest Diagnostics (#PTA). Research demonstrates that skin in a gas (#LNG) well is a function of temperature. Significant JT cooling would be a function

Decreasing JT Effects = Cleaning-up

Thermal Data Trends are Useful for Welltest Diagnostics (#PTA). Another common effect is for the temperature data in gas (#LNG) wells to exhibit an increasing trend (i.e. less JT cooling) while

Thermal Warming = Liquid Slugging

Thermal Data Trends are Useful for Welltest Diagnostics (#PTA). Downhole temperature data provide a useful diagnostic tool for understanding #welltest behaviour. Often thermal data offer the only indication of anomalies. Thermal

PVT Corrected Radial: s = +1, k = 24 mD

As we can see from the real gas law (pv = nZRT), changes in Temperature (Delta-T) also alter the pressure/volume term, thus affecting #welltest pseudo-pressure

Normal Pseudo-pessure/time: s = -1, k = 14 mD

As we can see from the real gas law (pv = nZRT), changes in Temperature (Delta-T) also alter the pressure/volume term, thus affecting #welltest pseudo-pressure

Joule-Thompson Cooling Effects Alter Pressure Transient Analysis Results. Western Canada Sedimentary Basin #welltests are often conducted in gas (#LNG) bearing formations. At the sandface, during production, Joule-Thompson (JT) cooling is the thermal effect most often

There are many useful applications for surface pressure data instruments, besides those already described. Optimization or surveillance purposes for determining timing for the running or pulling of subsurface pressure recorders or termination of critical #welltests. Surface casing-vent tests can

It is common practice in pumping oil wells
to use acoustic well sounder instruments (#AWS) to obtain reservoir pressure
buildup data without pulling rods and pump. With this method each pressure measurement is tied to a liquid
level shot,

Electronic surface pressure gauges have several fundamental advantages over acoustic well sounder instruments (#AWS). First, the sampling rate is significantly higher, whereas acoustic instrument sampling rates are controlled by the liquid level nitrogen gas shot frequency. Second, an electronic

Valid interference
#welltest results can be obtained from water injection wells, flowing oil wells,
and pumping oil wells. For
this example, pressure buildup data were obtained on a pumping oil well using both an acoustic well sounder and an

It appears only
logical that surface pressure data could prove useful for interference #welltesting in high permeability gas zones. Valid
results have been derived from both producing wells and injection wells. This example illustrates the surface pressure data
trace

Gas (#LNG) wells coming on stream in November actually trumped oil wells. Seven Generations led the gas surge, while Torxen sticks with oil. Great news to see the upswing going into winter.

Gas pops ahead

Perforation Inflow Distribution Diagnostic (#PID) #welltests can differentiate inflow ratios in multi-layer completions. By perforating subsequently better layers, an increase in surface pressure buildup slope is equal to an increase in gas inflow. It may be necessary to blow

Perforation Inflow Diagnostic (#PID) #welltests can be conducted in high permeability systems. Analytical results are useful for testing-on-the-fly decisions, tie-in decisions and facility infrastructure planning. For specific fields and pools, correlations can be developed whereby tie-in decisions can be

Production Testing crews take note: daylight savings time changes should NEVER be adjusted during a #welltest. Production tests MUST terminate in whatever time standard the test was started in. Pressure recorder clocks aren’t going to stop for an hour,

Pre-frac’ #welltests have proven successful using closed chamber methods. Surface pressures are recorded during perforation. The surface pressure buildup is proportional to gas influx into the closed chamber (wellbore). Quantitative order-of-magnitude results (kh, s’) can be estimated using Perforation

Sometimes using surface pressure data is the only practical testing method available. This example illustrates a #welltest where downhole gauges were set below an open sliding sleeve that was above the perforations. Valid pressure transient data were totally obliterated

Surface pressure data recorders
can be a valuable #welltesting tool. Validity of the technique is demonstrated
by two illustrations. This example flow and buildup #welltest was conducted on a 350 m low density sweet
gas well with both subsurface

If a liquid level is the only requirement then a wellbore schematic with tubing data (for collar counts), and gas properties (for velocity calculations) are sufficient. An appropriate natural gas relative density (i.e. a mixed gas) is critical for

While we’re featuring #AWS surveys, who remembers these 10 Point Calipers for reading paper charts? Google doesn’t even seem to know anything about them. They make counting collars easier, and more accurate, as sound waves actually speed up with

Factory setting paper chart speed for an Echometer™ model D #AWS is 9.2075 cm/s. This can change with age, environment, level of use, and battery charge. Don’t pull on the chart as it comes off the machine. Some

Sonic surveys can also be conducted down: an annulus (casing) with coiled, endless, or seamless tubing installed; inside coiled tubing; inside casing only; even inside drill pipe. Acoustic velocity methods are then employed for depth calculations. This requires an

Great to see an upswing in new production activity early this Autumn, for both oil and gas wells coming on stream. Narratives around #LNG sound better every month, too, with positive announcements recently, shipping to both east and west

Be sure to actually count every collar!  The field method of marking the first 10 collars on a cigarette pack, and quickly extending the measurement to the liquid level can result in significant errors! The sound wave actually speeds

The most familiar application of an #AWS is
a #welltest down the annulus (casing) to determine the liquid level depth by
counting tubing collars. Jointed tubing sections are screwed together with a
collar which is an obstruction
(thicker than

Most #AWS instruments have two amplitude (attenuation) settings: collars and liquid. This is analogous to a volume control, the collar setting is turned up listening for quiet reflections while the liquid setting is turned down listening for a loud

The most common method of creating an #AWS sound wave is to charge a gas gun chamber with compressed N2 or CO2. When this is released instantaneously into the wellbore an explosion impulse is created. An alternative method, in

Application of the #AWS for oil well pressure build-up surveys is well documented and avoids pulling rods and pump. Sonic surveys are also useful in a variety of other #welltest circumstances, including clean-up operations, gas (#LNG) well testing, and

Acoustic well sounders (#AWS) are sonar or sonic instruments. A small gas impulse at surface generates a sound wave, which travels down the wellbore. A microphone picks up the amplitude of reflected sound waves. The signal is recorded on

Wow, a 65% year/year decline in oil wells coming on stream in August. In other words, only 35% of the oil activity compared to 2018. Gas (#LNG) has been fairing better lately, with 60% of

In Canada, petroleum well testing is
controlled by provincial Boards, each with a variety of rules, regulations, and
submission requirements:

Alberta Energy Resources Conservation Board (#AER)British Columbia Oil and Gas Commission (#BC-OGC) Saskatchewan Industry and Resources

Frac’ sand returns (an abrasive) should be eliminated,
before running subsurface pressure recorders. Load fluids should be minimized, before conducting a single or multi-point
test gas (#LNG) #welltest. Clean-up
gas volumes are important for welltest analysis (#PTA) and reservoir

Gas (#LNG) #welltest
metering requires measurement of several parameters to solve the
equation-of-state: temperature, static pressure, and differential pressure. Gas
gravity (density), composition (H2S, CO2, N2)
and properties (pPc, pTc) should
also be known.

Critical

The most basic of production #welltests is to blow a gas (#LNG) well to atmosphere through a bean choke or critical flow prover. A small water knock-out separator can be added for minor liquids.

Production testing is a generic term for #welltesting through portable facilities. Usually production testing is done prior to tie-in for commercial operations. Production tests clean up wells and help define deliverability or productivity for economics and facility design. Production

In Canada, petroleum well testing is mandated
and controlled by provincial boards, each with a variety of rules, regulations,
and submission requirements:

Alberta Energy Regulator (AER)British Columbia Oil and Gas Commission (BC-OGC)Saskatchewan Industry and Resources (SIR)

In Canada, petroleum well testing is mandated and controlled by provincial boards, each with a variety of rules, regulations, and submission requirements:

Alberta Energy Regulator (AER)British Columbia Oil and Gas Commission (BC-OGC)Saskatchewan Industry and Resources

Differentials should be created for both #welltest pressure and temperature traces, for quality control and data validation. Liquid shifts are most clearly exhibited by differential diagnostics. Drift is also evident from the differential. Every effort should be undertaken to

Temperature data are a
primary #welltest measurement (i.e. not calculated like pressure data) and should
be examined for quality control and anomalies. Temperature data are a good
indicator of wellbore and reservoir characteristics.

Joule-Thompson cooling

Pressure buildup data
should always be examined for #welltest analysis (#PTA) quality control and anomalies.

Several phenomena might cause data
anomalies immediately after shut-in. Phase redistribution (gas going back into
solution) can cause a hump

Most often the initial pressure is just before purging portable production test facilities. This operation usually causes one of two patterns. If the wellbore is gas filled, a characteristic drawdown spike occurs. If there is liquid in the hole,

When #welltest recorders are run into a well they are measuring pressure vs. time (Dp/Dt). Liquid levels can be observed based on changes in the slope. Approximate liquid levels can be calculated assuming a constant running speed (Dd/Dt). This

Pressure recorders are available in two
basic types: strain gauges for general usage and quartz gauges, with higher resolution,
where better accuracy is required. Strain or quartz elements provide a primary amplitude signal, from
which pressure is inferred.

Braided electronic wireline (e-line) instruments include open hole logs (sonic, neutron) and production logs (pressure, temperature, and gradiometer recorders, and flow spinners), or even video cameras. For welltesting, pressure recorders (bombs) are the primary slickline instrument.

Wireline (Slickline) is one method of
running various measuring instruments and tools into petroleum wellbores. Basically, subsurface devices are
attached to the end of a long spool of wire, instruments are then lowered
down hole and winched back up.

An Isochronal #welltest in gas wells (#LNG) can be analyzed
for Laminar-Inertial-Turbulent (LIT) effects. Transient #AOF magnitude and turbulence
factors will be especially relevant if there are sour gasses and #AER blowout notification/evacuation
plans. Drawdown magnitude (%) should be

For the original 4-Point Isochronal #welltest
theory in gas wells (#LNG),
incremental flow and shut-in pressures needed to reach
stabilization. Sequences

In gas wells (#LNG) involve sequences of alternating flow and shut-in periods. Inflow rates are incremented for each point. In Alberta the #AER requires an isochronal test when the transient AOF >300 e3m3/d, mainly for sour gas blowout considerations.

We check the #AER Initial Outstanding List every week (due diligence). It’s surprising how many times #welltests which we have analyzed (#PTA) and submitted (for regulatory compliance) pop up. It’s often because the GCI doesn’t match the measured depth

In high deliverability gas (#LNG) wells help to quantify turbulence factors for rate-dependent skin and tubing performance evaluations. An isochronal #welltest can even illuminate blocked, crimped, or parted tubing issues. In Alberta, #AER regulations stipulate that all gas wells

Formation Leak-off Tests are a simple, effective,
economical #welltest strategy for #AER
Initial Pressure compliance in oil and gas (#LNG) wells. After landing a horizontal multi-stage frac’ string,
run recorders, open (burst) the toe hydro-port, and monitor the pressure

Mini-Frac’ or DFIT (Diagnostic Fracture Injection Test) is another #welltest alternative that might be worth considering to satisfy #AER Initial oil and gas (#LNG) well test requirements. In horizontal wellbores mini-frac’s can be successful if conducted through the toe

Might be worth considering to satisfy #AER Initial Pressure requirements for oil and gas (#LNG) wells. Underbalanced conditions result in fluid inflow causing a Closed Chamber pressure build-up (similar to a Drill Stem Test, DST). Overbalanced wells react by

Include perforation Inflow diagnostics (PID) and Fracture Fall-off or Formation Leak-off technologies. Impulse and Closed Chamber (DST) theory combine to offer simple, economic analytical (#PTA) options for satisfying #AER initial compliance regulations for both oil and gas (#LNG) wells.

Unconventional #welltest
programs include perforation Inflow diagnostic tests (PID), Formation Leak-off tests
and Fracture Fall-off tests (FLO), and Mini-Frac’ or Diagnostic Fracture Injection
Tests (#DFIT). These simplified methods are now in common usage providing
economical alternatives for compliance with

Re: AER Directive 40 (aka Guide 40) Initial Pressures… Traditionally new oil and gas (#LNG) wells were cleaned up before a single point flow and build-up #welltest was performed. This method is still valid, with pressure transient analysis (#PTA)

D40: #AER Directive 40 (aka Guide 40) Initial Pressures… With a minimum eight hours (8 h) of subsurface #welltest pressure data, it doesn’t matter whether-or-not the test meets the 2 kPa Rule, if the data are analyzable. Pressure Transient

D40: #AER Directive 40 (aka Guide 40) Initial Pressures… What’s not specifically clear in D40 is that Pressure Transient Analysis (#PTA) is an acceptable #welltest protocol for estimating a p* for Initial Pressure Oil and Initial Pressure Gas (#LNG)

Allows for an Initial or Annual #welltest to be submitted without analysis (#PTA). Conventional static gradient surveys, with a 10–15 minute
on-bottom stop, are acceptable. Sometimes the extended gauge won’t pass the 2
kPa Rule, but the gradient will,

For shut-in durations <14 days allows for an
Initial or Annual #welltest to be
submitted without analysis (#PTA). Extended
wireline, surface box, and acoustic well sounder (AWS) tests are submitted in
the TRG.pas (transient gauge) format. If the intent

For shut-in durations <14 days allows for an
Initial or Annual #welltest to be
submitted without analysis (#PTA). Static
gradient survey and ‘single shot’ AWS data are submitted electronically to the #AER in the GRD.pas format. Gradient
recorders must

For shut-in
durations <14 days allows for an Initial or Annual #welltest to be submitted without analysis (#PTA). Note the #AER
computer check has built-in leniency and will accept pressure changes <±2.5
kPa/h. Static gradient and ‘single-shot’ AWS files

Doubles For Initial Test… Mini-frac’ or Diagnostic
Fracture Injection Tests (#DFIT)
help double your #welltest
efficiency if pressure gauges are downhole. G-Function analysis estimates
closure stress, pore pressure, and leak-off type. After-Closure analysis may
provide an estimate of flow

Doubles For Initial Test… Mini-frac’ or Diagnostic
Fracture Injection Tests (#DFIT)
help double your #welltest
efficiency if pressure gauges are downhole. Program pressure recorders for
rapid data sampling (1 sec). Do a Leak-off Test (LOT) to confirm wellbore
integrity.

Doubles For Initial Test… Mini-frac’ or Diagnostic
Fracture Injection Tests (#DFIT)
help double your #welltest
efficiency if pressure gauges are downhole. To satisfy #AER Initial Requirements for Oil or Gas (#LNG) wells a minimum shut-in of 8 h is

Doubles For Initial Test… Mini-frac’ or Diagnostic Fracture Injection Tests (#DFIT) help double your testing efficiency if pressure gauges are downhole. First, a successful test helps estimate hydraulic fracture closure pressure and reservoir flow properties—valuable information for stimulation programs.

Time to plan for our #AER Annual Pressure Requirements.
Surface pressure recorders are fine for an annual #welltest — the caveat for gas (#LNG)
wells being that there cannot be a liquid level above the top perforation. Measuring
the

Time to plan for our #AER Annual Pressure Requirements. D40, section 4.5.7, states that  “…the minimum number of pressure surveys should equal about 25 % of a pool’s producing well count. Based on quarter section spacing for oil pools

Time to get low priority #welltest odds-and-ends off your desk. It’s also when we should be planning for our #AER Annual Pressure Requirements. Popular annual welltest methods include acoustic well sounder (AWS) for pumping oil wells, and surface pressure

A great time to get miscellaneous, low priority #welltest projects off your desk. It’s
also when we should be planning for our #AER
Annual Pressure Requirements. Plan ahead to
coincide with a scheduled plant turn-around, routine maintenance program, or

We would like to extend our sympathy and understanding to all of our fellow Calgarians during this unprecedented natural disaster. This catastrophe has obviously impacted everybody in our community, and the economic ripples will be felt across Canada. My parents

ERCB–D40, section 4.5.7, states that “…the minimum number of pressure surveys should equal about 25 % of a pool’s producing well count, based on quarter section spacing for oil pools. This translates to one survey per productive section. For gas

April seems to be a perfect time to mention some of our favourite tools that keep us lean, light, and charged while travelling. Our Targus Laptop Charger is essential for reducing cable clutter and transformer weight. Powering two devices at

April seems to be a perfect time to mention some of our favourite tools that keep us lean, light, and productive while travelling. Our most coveted recent acquisition was a Lenovo ThinkVision LT1421 USB monitor. This portable 14″ LCD screen

The ERCB has published the 2013 list of Annual Pressure Requirements. Don’t forget that surface data and acoustic well sounder (AWS) surveys are acceptable for compliance. Since we have a whole year it is a good idea to coordinate testing

Perforation Inflow Diagnostic (PID) tests satisfy ERCB Initial Pressure requirements. These simplified tests, now in common usage, provide an economical alternative to traditional methods. Basically the well is perforated under-balanced, and the subsequent closed chamber pressure build-up is monitored with

Perforation, fracture fall-off, and formation leak-off tests satisfy ERCB Initial Pressure requirements. These simplified tests, now in common usage, provide an economical alternative to traditional methods. There are several different scenarios, depending on your completion operation logistics. One method is

Mini-frac’ or Diagnostic Fracture Injection Tests (DFIT) help double your testing efficiency if subsurface pressures are recorded. First, a successful DFIT helps estimate hydraulic fracture closure pressure and reservoir flow properties – valuable information for stimulation design. Second, the resulting

What’s not specifically clear in G40 is that Pressure Transient Analysis (PTA) is acceptable for estimating Initial Pressure Oil and Initial Pressure Gas conditions.
    

Misconception #1: all tests have to pass the 2 kPa Rule. Not

Fantastic news for Canadian photographers: Bill C-11, the Copyright Modernization Act, became law November 7th, 2012. Canadian photographers will now own copyrights to all of their images, even if commissioned, hired, or employed to take pictures. Photographers have gained equal

I’m paranoid about data loss. I’ve seen years of accumulated information evaporate in a moment – fortunately not mine. Zip, tape, and floppy drives that could never be read again when the hardware died or technology simply marched on. Hard

Cool Tools that keep us connected whenever, wherever. We use a Talkswitch PBX to turn our land-lines into a VoIP system. This Canadian technology is amazing and economical for our small business. First it sends incoming calls to our computers

We did indeed, finally, thankfully, get rid of our exchange server – and moved several systems to The Cloud: e-mail, accounting, and back-up. We are very happy with all of our researched choices for software-as-a-service (SaaS) providers.
There are lots

We did indeed, finally, thankfully, get rid of our exchange server – and moved several systems to The Cloud: e-mail, accounting, and back-up. We are very happy with all of our researched choices for software-as-a-service (SaaS) providers.
We couldn’t wait

We did indeed, finally, thankfully, get rid of our exchange server – and moved several systems to The Cloud: e-mail, accounting, and back-up. We are very happy with all of our researched choices for software-as-a-service (SaaS) providers.
We registered with

We are coming out the other side of closing our office and moving home. Most technical issues have been resolved – but the server is still for sale (cheap!). Now that we have time to breath I can start uploading

Three separate inquiries in one week makes for an easy blog topic!
So, your Initial Pressure Gas (IP Gas) or Initial Pressure Oil (IP Oil) submissions have been accepted by the ERCB – but the UWI still shows up on

Perforation Inflow Diagnostic (PID) Tests are an excellent, and cost effective, method for obtaining a quality estimation of initial reservoir pressure conditions. As the name implies, these tests are conducted during or immediately after perforating – so reservoir pressure transients

Characterizing Reservoir Properties using Diagnostic Fracture Injection Testing (DFIT) was presented at a recent Society of Petroleum Engineers (SPE) luncheon. A great talk – and a great reservoir diagnostic test – as our example Level 2 eREPORT illustrates: DFIT2 Mini-frac’

The second sample eREPORT I’d like to point out is PTA2 Theoretical 4pt AOF – Pressure Transient Analysis Level 2. Our Level 2 eREPORT is simplified in terms of write-up: only a summary of analytical results and conclusions.  Level 2

We now have a variety of sample eREPORTS available for perusal. The first one I’d like to draw your attention to is titled PTA1 Comprehensive: Pressure Transient Analysis level 1 comprehensive. This is the traditional, legacy style, turnkey eREPORT for

Finally – a blog on Welltesting!
It’s taken a while to get this together. Mostly because I’ve been too busy and needed someone to help get the new WordPress based web site designed and loaded. Now that it’s up I

We pioneered digital engineering eReports to allow you to reduce, or even eliminate, paper copies, and lighten up your well files.

We tell it like it is in practical, easy to understand, concise English. We employ visual literacy concepts to make complex subject matter easy to comprehend.

With more than 34 years practical experience we know conventional testing is critical for completion and reservoir engineering. But we also know test alternatives to save you money!