drilling – LDI Training

Oil companies, oilfields in Indonesia, Pipelines

The Amazing Rise of Medco Energi

Medco Energy International is the first publicly owned oil company in Indonesia.

Medco is celebrating more than forty years of presence and continuing successes as one of the leading energy companies in Indonesia and Southeast Asia.

Medco Energi International became a public company in 1994, and today it operates in eight countries.

It has interests in oil and gas exploration and production, geothermal power generation, gas distribution and trading, and mining.

The year 2022 is a wonderful year for Medco Energy. It booked net profits of 531 million USD in 2022 which is more than 10 times higher than the US$ 47 million it made in 2021. The company produced 163 million barrels of oil equivalent (BOE) in 2022, a 73% increase over the previous year.

The Beginning of Medco

Medco Energi has come a long way in a short time since it started as an oil drilling service company in 1980, Meta Epsi Pribumi Drilling Company (MEDCO).

Founded by Mr. Arifin Panigoro, Medco Energi was a visionary and a trailblazer ever since its beginning.

The Acquisition of Stanvac Indonesia

The first breaks that made Medco became big and successful were the acquisition of Stanvac’s oil and gas assets in South Sumatera in 1995, and the following discovery of the big oil fields in Kaji and Semoga in the Rimau Block, in South Sumatera.

Stanvac Indonesia, set up by Standard Oil of New Jersey in 1912, was one of the oldest and biggest oil companies in Indonesia during the Dutch colonial era.

The Acquisition of ConocoPhillip’s Interest in West Natuna Sea Block B PSC

Medco Energi further expanded in 2016 when it purchased ConocoPhillips’s 40% interest in the West Natuna Sea Block B and took over the operatorship of the block.

This acquisition added substantial gas and liquids reserves and increased Medco Energi’s daily production by over 35%.

The block is in approximately 300 feet of water and had 11 offshore platforms, four producing subsea fields, and one FPSO – the Belanak FPSO – in addition to two dedicated floating storage and offloading vessels.

The Belanak FPSO was described as one of the most complex FPSO in the world. It was the first offshore liquefied petroleum gas (LPG) facility on a floating vessel in the Asia Pacific region when it was commissioned in 2004.

The fields include the Belanak field, South Belut field, Hiu field, Kerisi field, North Belut field and Bawal field.

The produced natural gas is sold to Singapore and Malaysia through a 654 KM long 28 inch gas pipeline.

Medco Energi also assumed the operatorship of the Onshore Receiving Facility in Singapore following the acquisition.

Acquisition of Ophir Energy

Medco Energi Internasional continued to expand by acquiring Ophir Energy, a London-based independent in 2019.

The acquisition of Ophir Energy increased Medco Energi’s daily oil and gas production by 29% to 110,000 BOE per day.

By taking over the operatorship of Ophir Energy’s offshore Bualuang field in Thailand, Medco Energi became a leading regional oil and gas player in South East Asia.

Acquisition of Corridor PSC and Transasia Pipeline

On March 3, 2022, Medco Energi acquired the entire remaining assets of ConocoPhillips in Indonesia..

Through this acquisition, Medco Energi is now the operator of the Corridor block with 54% interest and has 35% ownership of Transasia Pipeline Company.

The Corridor PSC has two producing oil fields and seven producing gas fields located onshore South Sumatra, Indonesia, adjacent to MedcoEnergi’s existing operations in South Sumatra. The Corridor is the second-largest gas-producing block in Indonesia.

Through Transasia, MedcoEnergi now owns a minority interest in the gas pipeline network supplying Central Sumatera, Batam, and Singapore customers.

Epilogue

With this latest acquisition, Medco Energi is now one of the largest oil and gas operators in Indonesia.

Besides acquiring producing assets, Medco Energi is also active in exploring new oil and gas reserves.

Its 2020 exploration drilling campaign in the South Natuna Sea Block B was 100% successful. It tested hydrocarbon in all the four exploration wells it drilled. The wells are Bronang-2, Kaci-2, Terubuk-5, and West Belut-1.

Medco Energi is planning to develop these fields.

As Medco Energi celebrates its more than 40 years of progress, with its solid management team, it certainly will continue to march toward an even brighter future.

Top Management Team of Medco Energi

Here is the top management team of Medco Energi.

Muhammad Lutfi – President Commissioner

Hilmi Panigoro – President Director

Roberto Lorato – Chief Executive Officer

Anthony R Mathias – Chief Financial Officer

Ronald Gunawan – Chief Operating Officer

Amri Siahaan – Chief Human Capital and Business Support Officer

Myrta Sri Utami – VP Corporate Planning & IR

Siendy K Wisandana – Head of Legal Counsel and Secretary

As a final note, Dr. Arifin Panigoro, the man who started it all and the founder of Medco group of companies died on 27 February 2022 at age of 76.

Written by Jamin Djuang – Chief Learning Officer of LDI Training and author of the published book The Story of Oil and Gas: How Oil and Gas are Explored, Drilled and Produced.

Mud logging

The Job of A Mudlogger

Mudlogging is one of the many important activities during drilling, especially in exploration drilling. Third-party service providers make up about half of the workforce on an offshore rig. With so many hi-tech and specialized operations being performed at all stages of the drilling operations it’s imperative that experts in their field perform these tasks.

The job of the “mudloggers” is to monitor the drilling operations from the time the well is spudded to the time the well is safely drilled, tested and secured for either production or abandonment.

“Mudlogger” is the generic term used to describe the field specialists who monitor the well and also collect samples for the geologist. The career progression for a mudlogger is to generally start as a sample catcher while they learn about the drilling operations, then progress to a mudlogger and with further experience, become a data engineer.

Sample Catchers

Dedicated sample catchers aren’t always part of the team but they often get “thrown in” as a complementary part of the mudlogging services. They don’t need to have any prior experience in working offshore or as a mudlogger, so it’s a very good entry-level job and is generally the starting position for a graduate geologist (or anyone else) who wishes to work offshore. Although you don’t need to be a geologist to be a sample catcher, most of them will be and will go on to get trained as a mudlogger.

Sample catching is without a doubt the least glamorous and lowest paid of all jobs on the rig…but you have to start somewhere! The role of a sample catcher is to provide the most basic geological data acquisition on the rig and to assist with all general activities when possible. The main duties of the sample catcher are:

Ensuring that representative geologic samples are caught throughout the drilling or reaming phases of the well program. This is done by collecting cuttings (drilled rock) samples, from the proper “lagged” (explained below) depths and at the proper intervals as required for evaluation. These samples are collected off the shale shakers, screened and washed, divided into correct portions, and packed into sets for the Client, partners, and government agencies. They may also have to assist in core recovery and packaging as required.
Preparing a clean “cuttings” sample on a sample tray for the wellsite geologist and mudlogger, who will then examine it under the microscope and describe the lithology of the drilled formation.
Assisting mudloggers and data engineers to perform regular and frequent calibration checks of instruments, perform normal routine maintenance of sensors and other equipment and also assist logging crew with rig-up/rig-down procedures.

The sample catcher reports directly to the mudlogging crew who will ensure his duties are performed correctly. This may include on-the-job training as required. They work out of the mudlogging unit, which is always close to the shale shakers and these are generally one or two levels below the drill floor.

The shale shakers are vibrating screens that separate the drilling fluid from the drilled rock cuttings. The “shaker house” is a very noisy place and double hearing protection must always be worn. There will be multiple shakers to accommodate the large volume of cuttings that can be produced when the drilling rate of penetration is high (i.e. they are drilling fast!). It’s a very “dirty” job and multiple layers of personal protective equipment need to be worn to prevent skin contact with the drilling mud, which can cause serious skin inflammation.

Mudloggers and Data Engineers (DE)

Mudloggers and data engineers are responsible for gathering, processing and monitoring information pertaining to drilling operations. They don’t only collect data using specialist data acquisition techniques – they also collect oil samples and detect gases using state-of-the-art equipment.

The information amassed by these guys is analyzed, logged and then communicated to the team that is responsible for the physical drilling of the well. Without the help of the mudlogger, the drilling operations would be less efficient, less cost-effective and much more dangerous. The mudlogger is vital for preventing hazardous situations, such as well blowouts.

They also provide vital assistance to wellsite geologists and write detailed reports based on the data that is collected. Being an entry-level position, employees will be given a mixture of ‘on-the-job’ training and expert in-house training courses, which cover different aspects of drilling operations. A major part of the training will focus on the use of specialist computer software.

Typically, you will need a degree in geology to start a career as a mudlogger. However, candidates with degrees in physics, geochemistry, chemistry, environmental geoscience, maths or engineering may also be accepted.

Along with the sample catchers and data engineers, the mudloggers work out of the mudlogging unit, which is a pressurized sea container-type of office, which is positioned close to the drill floor and shaker house.

The unit will have an air-lock compartment when you first enter it so as to maintain the positive pressure within the unit whenever somebody leaves or enters the unit.

This is the main control room for monitoring the drilling operations and is full of sophisticated and delicate equipment and computer systems. Positive pressure needs to be maintained to ensure the air pressure inside the container is higher than that of the outside area to prevent contamination of sensitive monitoring equipment – and also to ensure the safety of the crew working inside the unit should the outside air become contaminated through uncontrolled releases of hydrocarbons from the well.

mudloggingunit-amanda — A mudlogging unit

One of the most important tasks of the mudlogger is to oversee the collection of not only geological samples but also mud and gas samples from the well during drilling operations. To be able to do this accurately they have to know the exact “lag time” (or “bottoms-up time”) that it will take for the drilled cuttings or mud and gas to arrive at the surface after being drilled and circulated up the outside of the drill hole (annulus) while suspended in the drilling mud. The lag time maybe a few minutes in a shallow hole or as much as several hours in deep wells with low mud flow rates. To be able to work this time out accurately there are many factors that have to be taken into consideration. The lag time depends on:

the annular volume fluid
flow rate, which in turn requires knowledge of:
dimensions (internal diameter (ID) and outside diameter (OD)) of surface equipment, drill string tubular, casing and riser.
mud pump output per stroke, pumping rate, and efficiency.

While the computer’s software will work this out automatically, the calculated value may be incorrect if the operator has entered erroneous or incomplete values for the pipe or hole dimensions, or if the hole is badly washed out. This has to be monitored very carefully to avoid catching mud, gas and cuttings samples at incorrect depths.

Sensors

The mudloggers and DE’s monitor the drilling operations via a series of sensors that are placed at various locations around the drill floor, pit room, and shaker house.

The main drilling and mud parameters that are recorded are: hook movement, weight on hook, standpipe pressure, wellhead pressure, rotary torque, pump strokes, RPM, mud pit levels, mud density, mud temperature, mud resistivity, and mudflow.

These parameters are monitored in real-time and any deviances from the expected normal values must be immediately reported to the driller. The DE will view and monitor all the drilling parameters on a screen as shown below.

drilling parameters-amanda — A drilling parameter screen

The five most important monitoring tasks that the mudlogger and DE must watch out for are:

Rate of penetration increase, which could indicate they have drilled into a reservoir formation
Mud pit volume gain or loss, which could indicate the well is taking a kick, or losing fluid into the formation
Mudflow rate change
Mud density variation
Indication of oil or gas.

The mudlogging unit is a very confined workplace and there may be up to several people working in there at any one time, especially if it’s a “combo” unit, which houses the mudloggers, MWD engineers and possibly also the directional drillers.

Generally (but not always), the same service provider company performs all of these roles so it is quite common for data engineers to progress into a role as an LWD/MWD engineer. Other common career progressions for mudloggers/data engineers are as a wellsite geologist or drilling fluids engineer (mud engineer).

inside a mudlogging unit - amanda — Inside a mudlogging unit

The complete list of responsibilities of the mudloggers is too exhaustive to detail in this article but the above-mentioned roles are the main ones. Like most jobs on the rig, daily reports are a big part of the data engineer’s responsibilities.

The mudloggers report directly to the wellsite geologist, who are generally working in the mudlogging unit alongside them. Because the mudloggers are required to monitor the drilling operations from the commencement of drilling they will always be employed on a permanent rotating roster, which is generally 4-weeks on, 4-weeks off.

This article was written by Amanda Barlow, a wellsite geologist and published author of “Offshore Oil and Gas PEOPLE – Overview of Offshore Drilling Operations” for a beginner guide to working in offshore drilling operations, and “An Inconvenient Life – My Unconventional Career as a Wellsite Geologist”

Another great book you may want to read if you like to get an overview of oil exploration, drilling and production is “The Story of Oil and Gas”: How Oil and Gas Are Explored, Drilled and Produced”.

Uncategorized

The Job of a Wellsite Geologist

The wellsite geologist (WSG) is the source of operational geological information on the rig and is responsible for all geology-related administrative wellsite activity. They are the operating company’s eyes and ears on the rig and as such, have to make sure that all possible geological and drilling information is gathered in a concise and timely manner.

While the wellsite geologist works in close cooperation with the company man on the rig he is not actually under his authority. Instead, the WSG reports directly to the “Operations Geologist” who is the “shore-based” intermediary between the geologist on the rig and the geology team in town who will be analyzing all the data. The unusual chain of command for disseminating key official geological data from the wellsite geologist follows this line of reporting:

WSG (rig) => Operations Geologist (town) => Drilling Superintendent (town) => Company Man (rig)

While the wellsite geologist is required to immediately notify the company man of any pertinent drilling and geological information, the company man generally cannot act on the information until the town-based drilling superintendent has officially confirmed it.

The wellsite geologist will report all key geological and drilling data to the operations geologist immediately as it comes to hand. It is then the responsibility of the “ops geo” to disseminate this information to all members of the onshore geology and drilling teams who need to know the information for decision-making.

All key drilling decisions are made in collaboration with every department involved in the drilling of the well to ensure that well control barrier criteria are met and any decisions made will not compromise the integrity of the well or process safety systems.

At the commencement of drilling, when the well will be drilled “riserless” with no cuttings coming to surface, there will often only be one wellsite geologist on the rig. There may be two or even three casing strings run before the riser is finally run and drilled cuttings are brought to the surface.

The wellsite geologist will be needed during these stages of drilling to confirm that suitable geological formations have been intersected in order to successfully set casing. This task is commonly referred to as “calling casing point”. It is critical that the casing shoe for the conductor and surface casing is set deep enough to withstand pressure from a “kicking” formation further down.

Surface casing is run to prevent caving of weak formations that are encountered at shallow depths. The wellsite geologist needs to identify when a competent formation is intersected to ensure that the formation at the casing shoe will not fracture at high hydrostatic pressure, which may be encountered later in the drilling of the well.

Because there are no drilled cuttings coming to surface all geological data is interpreted from one, or a combination of both, of the following sources:

Drilling parameters such as ROP (rate of penetration) and torque when there are no LWD (Logging While Drilling) tools in the BHA (Bottom Hole Assembly).
Real-time Gamma Ray and/or Resistivity data from downhole LWD tools.

Once the surface casing has been set and the BOP (blow out preventer) and riser are run to the seabed, all drilled cuttings will then be circulated to the surface, which means the days get a whole lot busier for the wellsite geologist. From this stage on there will generally be two wellsite geologists operating back-to-back 12-hour shifts.

Responsibilities

As the acting representative for the operating company’s geology team, the wellsite geologist will have the following responsibilities:

Evaluating offset data before the start of drilling
Analyzing, evaluating and describing formations while drilling, using cuttings, gas, formation evaluation measurement while drilling (FEMWD) and wireline data
Comparing data gathered during drilling with predictions made at the exploration stage;
Advising on drilling hazards and drilling bit optimization
Making decisions about suspending or continuing drilling. Ultimately, it’s the wellsite geologist’s responsibility to decide when drilling should be suspended or stopped.
Advising operations personnel both on the rig and in the onshore operations office about any pertinent geological or drilling information as it arises.
Supervising mudlogging, MWD (Measurement while drilling)/LWD (logging while drilling) and wireline services personnel and monitoring quality control in relation to these services.
Keeping detailed records, writing reports, completing daily, weekly and post-well reporting logs and sending these to appropriate departments.
Maintaining up-to-date knowledge of LWD and MWD tools and status of all equipment onboard and in transit to make sure the equipment is available and in working order when it is needed.

In expected HPHT (high-pressure high temperature) wells it is critical the wellsite geologist can identify (and immediately communicate) any identifying signs of increases in pore pressure. These can include the following telltale signs:

Changes in flow rate and active mud system volumes. If the formation pressure becomes higher than the hydrostatic pressure being exerted by the circulating drilling fluid then the mud will become “underbalanced” and the well will “kick”. If this kick isn’t detected early enough then a catastrophic blowout could occur.
Presence of “cavings” coming over the shakers. When drilling over-pressured shales, it is common for the formation to undergo stress relief causing chips of rocks to cave from the borehole wall. These overpressure “cavings” tend to be larger than normal cuttings and maybe concave or propeller-shaped.
Increase in ROP (rate of penetration) and volume of cuttings. A pressure transition zone will make drilling easier because of the trapped water-reducing compaction and the increase in pore pressure reducing differential pressure, allowing cuttings to be released more easily into the mud stream.
Changes in LWD data, in particular, resistivity and sonic, density and neutron.
Changes in drilling parameters, especially torque, drag, and overpull. This can be due to deterioration of borehole integrity causing an increase in the volume of cuttings and cavings in the circulating mud.
The rise in background gas level, changes in the composition of the gas, or presence of “connection” gas, which is a result of swabbing downhole hole when the pumps are turned off to make a connection (add another stand of drill pipe).
Changes in pump pressure. An influx of gas into a well may reduce the density of the drilling fluid and therefore it will require less pressure to circulate the drilling fluid.
Change in properties of mud.
Changes in downhole temperature. Generally, there will be a slight decrease in temperature immediately above the over-pressured zone and then a steady increase with depth at a higher rate than in the normally pressured zone above.

If the wellsite geologist identifies any potentially hazardous changes in the drilling, the driller and company man must be notified immediately, and then the operations geologist will be notified.

If a potentially dangerous situation is recognized then the drilling will be stopped immediately while the company man either makes a decision on what to do next or waits for official instructions from the drilling superintendent in town on how to proceed.

The wellsite geologists spend most of their time working in the mudlogging unit (like the hardworking one in the photo above J), which is where all the monitoring equipment for the rig is located and also where the mudloggers/sample catchers will deliver the cuttings samples for them to inspect and describe.

All rock cuttings are inspected under a microscope and a detailed description is written for every sample that is generally collected in composite 5, 10 or 20 m intervals.

Cuttings Descriptions

The cuttings descriptions need to be very detailed and follow an industry-standard format that includes (but is not restricted to) the following observations:

Rock types and percentage of each found in the sample
Color
Texture
Grain or crystal size
Sphericity, roundness, and sorting of sandstone grains
Type of cement and/or matrix
Any fossils or accessory minerals
Presence of hydrocarbon indications, such as fluorescence or “show”
Estimate of porosity

A detailed well log is created combining all the cuttings information, LWD, and MWD data and drilling parameter data, and submitted along with a daily report every 24 hours. When the wellsite geologist finishes the shift and hands over to the next shift they have to have all of the reporting and samples descriptions up-to-date at the time of them handing over.

To become a wellsite geologist, you’ll need a degree in geology or possibly even chemistry, geochemistry or geophysics. There is no formal wellsite geologist qualification, but you would need to obtain knowledge in areas such as wellsite and offshore safety management, wellsite operations, formation evaluation of wireline, FEWD logs, and risk assessment before starting as a wellsite geologist.

Most wellsite geologists start their offshore career working as a mudlogger, MWD engineer or mud engineer and gain knowledge in the fields that a WSG is responsible for. They also need to possess supervisory skills, the ability to work well under pressure and the ability to quickly make decisions.

As most wellsite geologists work as independent consultants and are employed on a contracting basis, it’s up to them to handle their own career progression. Any wellsite geologists who progress beyond this position will generally move into an operations geologist role, with a few even moving up into company man positions.

While a wellsite geologist might earn a lot per day there is little job security, and quite often no permanent rotation. They may only get flown onto the rig the day before drilling operations begin and flown off again immediately after the well is completed or wireline logging is completed. The date of your arrival and departure is quite often only known within days of it occurring so long-term social commitments are impossible to plan. You can either expect to have to fly out to the rig at very short notice or have unplanned months without any work…or even years when the industry is going through a downturn.

Like with many oil and gas roles, being a wellsite geologist can be a very demanding job but the rewards can certainly outweigh the risks if a sensible approach is taken to managing your time and finances. If unpredictability is not your thing then wellsite geology is not for you! Being away from home for several months of the year is part and parcel of the job so people with young families may find this job too demanding on their family life. This will always be the first and foremost decision you will have to make if considering to become a wellsite geologist.

This article is written by Amanda Barlow. Amanda Barlow is a wellsite geologist and published author of “Offshore Oil and Gas PEOPLE – Overview of Offshore Drilling Operations” and “An Inconvenient Life – My Unconventional Career as a Wellsite Geologist”.

Tag: drilling