Assets/ Basins/ Plants/ Institutes

A. Assets1. Mumbai High Asset, Mumbai2. Neelam & Heera Asset, Mumbai3. Bassein & Satellite Asset, Mumbai4. Ahmedabad Asset, Ahmedabad5. Ankleshwar Asset, Ankleshwar6. Mehsana Asset, Mehsana7. Rajamundry Asset, Rajamundry8. Karaikal Asset, Karaikal9. Assam Asset, Nazira10. Tripura Asset, Agartala

B. Basins1. Western Offshore Basin, Mumbai2. Western Onshore Basin, Baroda3. KG-PG Basin, Chennai4. Cauvery Basin, Chennai5. Assam &Assam-Arakan Basin, Jorhat6. MBABasin and CBM Development Project, Kolkata/Bokaro7. Frontier Basin, Dehradun

C. Plants1. Uran Plant, Uran2. Hazira Plant, Hazira

D. Institutes1. Keshava Deva Malaviya Institute of Petroleum Exploration (KDMIPE), Dehradun2. Institute of Drilling Technology (IDT), Dehradun3. Institute of Reservoir Studies (IRS), Ahmedabad4. Institute of Oil & Gas Production Technology (IOGPT), Navi Mumbai5. Institute of Engineering & Ocean Technology (IEOT), Navi Mumbai6. Geo- data Processing & Interpretation Center (GEOPIC), Dehradun7. ONGCAcademy, Dehradun8. Institute of Petroleum Safety, Health & Environment Management (IPSHEM), Goa.9. Institute of Biotechnology & Geotectonics Studies (INBIGS), Jorhat10. School of Maintenance Practices (SMP), Vadodara11. Centre for Excellence in Well Logging (CEWL), Vadodara12. Regional Training Institutes (RTIs), Navi Mumbai, Chennai, Sivasagar & Vadodara.

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QHSEQHSE stands for Quality Health Safety and Environment

In the QHSE talk delivered to us, we were informed of the various certificates and standards that ONGC complies with:

Q- Quality- IS0 9001:2000

H&S- Health & Safety- OHSAS (Occupational Health and Safety assessment series) 18001:1999

E- Environment- EMS 14001:2004

QHSE is of paramount importance in every aspect of our lives. The health and safety of a company’s employees is generally the top most priority before an assignment is taken up. More over Precautions and measures are taken to ensure the safety of the surroundings too i.e. environment.

For safety of personnel at the site, every site has a clearly marked Assembly Point believed to be a safe point. In case of an impending hazard all personnel are required to gather at the AP were further instructions are issued. Most people have clearly defined roles as to how they will tackle a disaster.

(Eg: In case of a fire it was designated that one person will check that the compressors are shut down while the other will rush to get the fire extinguisher.)

The HSE setup at ONGC is three tired:

1. The Apex Body: ( Corporate HSE body at Delhi)2. The Core Body: ( Regional HSE body at Baroda)3. The Line HSE body: (Asset Office)

The duties and functions of an HSE body at ONGC are as follows:

a) Up gradation of DMP and contingency plan.b) Drafting a recommendation code of practice for safety.c) Coordinating and training of personnel for firefighting and first aid etc.

2

Main Producing horizon of Different Area of Mehsana Field

Area Main producing horizon

Nort Kadi Kalol ,Mehsana , Linch

Sobhasan Sobhasan, MandhaliSanthal Kalol

Balol KalolJotana Mandhali , Linch

Nandasan

Kalol , Mehsana,Mandhali

Lanwa KalolBechraji Kalol

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4

SALIENT STATISTICS OF MEHSANA ASSET

Area: 6000 sq km

No. of fields: 27

Wells drilled: 1777

Oil wells: 1161

Flowing: 954

S/F wells: 233

A/L wells: 721

Gas wells: 16

Flowing: 11

Wells Abandoned: 269

Sick wells: 207

OIL(MMT) SG+GC (MMm3) FG (mmM3)PROVED 338.46 17941.80 2129.70

PROBABLE 12.49 802.90 29.40POSSIBLE 23.81 1559.60 275.90

TOTAL 347.76 20344.30 2435.00

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Visit to the Ignition trailerThe ignition trailer initiates the process of in-situ combustion which is generally sensitive, specialized and critical in nature.

Specialized and critical in nature .the trailer is a self contained movable unit equipped with a high pressure gas compressor ,air and gas control panel ,wire line winch etc,it regulates moniters and injects high pressure air and gas into the injector well.

Mobile van(ignition trailer van)

From Canada in 1989(petroleum company )

Normal pressure maintained at 95-97 kg/cm^2

TEB (tri ethyl borane) is lowered between (350-400)C

TEB burns in oxygen atmosphere.

For 1 m perforation heat generated : 3.1-3.2 heat calone

Air and gas ratio =55: 1

After 6 months when well in wet phase

Volume of air * 0.09 =vol of water injected

Water cools the system

For 1 week = 6 days air injection + 1 day water injection

For measuring the bottom hole temperature .thermocouple is used thermocouple starts from burner (heat shield) to the annulus a temperature panel displays the temperature of flame and other parts .

A lubricator assembly provides for transport though insitu combustion has a good EOR technique ,it also has some disadvantages like:-

It is highly expensive

Corrosion of tubing is also a problem

It produces undesirable H2S

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The tools involved in ignition trailer are:-

Gas flow meter

Winch cylinder

Compression unit

Burner arrangement

Casing and tubing pressure gauge

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VISIT to Sobhasan GGS CUM CTF, GCP and ETP

Sobhasan gas cum CTF is biggest CTF in Mehsana asset. The dispatched oil from this place is recived in Nalagan CTF. This is further transformed to Vadodra refinery. We visited to the all parts of the GGS cum CTF and saw different units involved in initial treatment of crude oil .we were taken to the control room from where all the parts of GGS was controlled and monitored.

Various steps involved in GGS are as follows:1) Oil from all the wells in Sohbhasan are collected in GGS unit different types

of pressure header. These are high pressure header. these are high pressure , medium pressure & low pressure header

HP = 4.5 kg / cm

LP = 2.5 kg/cm

Then crude is sent in vertical separator where the liquid separated from gas Gas is itself is used in GGS itself for heater treater and both heater Crude is sent to both heater to be heated to around 100 c After this crude is passed through heater treater where the oil emulsion is

feed from water to a larger extent and water collected is sent to affluent treatment plant ( ETP)

Heater treater has 3 section inside it .1) Heating section 2) Settling section3) Electrical section ( electrical coalescing)

The storage tank is of fixed root type. Gas from the vertical separator is sent to scrubber where the small amount of

oil present is removed and dry gas passes through it . oil is sent back to heater treater

There is a particular colour for each type of fluid flowing pipes. These are as follows :

Yellow - gas Brown – oil Light green – effluent waterBlue – instrument air Red – sire water

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VISIT TO ETP

1) Effluent tank ( 1300m) receives effluent water from CTF at 100 c2) Wash tank into which water from GGS and effluent tanks enters at 70 c3) Then effluent water is sent to settling tank where oil is separated from

water as oil come to the top surface. Oil is skimmed off the surface of water in settling tank.

4) In reaction dump, chemicals like alum, FeSO4, poly electrolyte were added to purity water, remove oil, bacteria.

5) From settling tank, water is sent to filler containing activated carbon filter. sludge from settling tank is put in sludge tank for drying .

6) Water after treatment is stored in a tank from where it is sent to the well site where water is used for injection deep inside earth.

CTF, Sobhasan

Crude oil from oil wells of Sobhasan comes to CTF. At CTF crude oil is separated from water present in it. Water is reduced to below (1- 1.5) %. Oil from this place is sent to storage tanks from where it is sent to Ahmedabad CTF.

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PMS, ARTIFICIAL LIFT & PTYS Production maintenance services are required to maintain unhindered flow of

fluid from the reservoir to the refinery. Maintenance services are required for maintenance of the flow lines .from well

head to required place, well bore to well head etc.

ARTIFICIAL LIFT SECTION

For artificial lift two methods are applicable

Mechanical - SRP Gas Lift

SRP

It has a NRV-Non Return Value. It is lowered with pump barrel, the NRV being at lowest position of barrel. Plunger is put inside the pump barrel .Plunger is put inside the pump barrel to which sucker rods are connected. Tubing is connected to pump barrel.

Sucker rod are ¾ , 7/8 ,1 “ diameter rod & 76m long.

SRP is positive displacement pump. But it is not suitable for suspended solid. Progressive cavity pump – spiral sucker rod.

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GAS LIFT

In this method high pressure compressed gas is injected through annulus.

Two type of technique:

a) Continuous liftb) Intermittent liftc) Gas lift values are attached to the production tubing ie between casing and annulus . values are

SPM .( side pocket mandrel). The valve is NRV ( non retuning value)

GLV DESIGN 1/8 4000-5000 scm 3/16 8000 scm

As gas passes through tubing the mobility of oil increases.

PRODUCTION TOOL YARD & SERVICES ( PTYS)

It is used for maintenance of production tools that are used in fields.

TOOLS are as follows:

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1) SRP2) Packers

a) Mechanical packer b) Tension packer c) Hydraulic packer

3) Tubing 4) Sucker rods 5) Bridge plug

EOR TECHNIQUE AND INSITU COMBUSTION AND VISIT INSITU

PLANTEOR-Enhanced Oil Recovery. It is type of tertiary oil production from well.

Different Oil Techniques

1. Thermala. Insitu combustion:-It is based on principle of heating of oil

bearing sand itself, thereby making it more mobile. Insitu is successful in Mehsana.

b. Steam injection- Steam flooding is done in this case which is also known as huff and puff.

2. Non-Thermala. Chemical EOR- Use of surfactant, alkali, polymer in

increasing the recovery from reservoir.b. Microbial EOR- Employed in Shobhasan field. Microbes

absorb waterand reduces water from the well.

BALOL FIELD

Reservoir : Sandstone

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Average Porosity: 28.0%

Permeability: 8-15 darcy

Avg.Depth:1050m

Insitu combustion:

This technique was implemented on a commercial scale in 1997. It gave new life to older wells. The recovery also increased to 2-3 folds from 6-15% to 39-45%. Incremental oil from these wells is 8000bbls/day Worth more than Rs.500 crores/year.

Various Zones During Combustion

1. Burnt zone2. Combustion Zone3. Coking zone4. Cracking and vaporizing zone5. Condensing zone6. Light Hydrocarbon zone7. Combustion Gases

Phases of Insitu

1. Inception Phase- Ignition of oil in vicinity of injector.2. Dry Composition Phase- Sustaining injection by air injection3. Wet combustion Phase- Cyclic injection of water

To reduce temperature after 6day air injection and one day water injection.

Insitu combustion technique in the heavy oil belt of Balol and Santhal oil fields of Mehsana asset has been successfully implemented.

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Visit to NK- GGS-4, Mehsana CTF &NK- ETP Oil from 14 self flow wells and38 SRP wells come here which is then classified

into low pressure (LP) and low level pressure (LLP). The crude after being mixed with water soluble chemical is send to bath

heater where the temperature is raised to 55°c. The crude is then send to vertical separator where liquid and gas is separated. The gas is then send to knock out drum where the oil revived is sent along

with separated oil while the gas is sent to compressor plant. The crude is then send to heater treater where the temperature is raised to72-

75℃ and the water is sent to ETP. The crude separated is kept in oil storage tanks.

The LP gas is sent to flare KOD. Here any liquid left is removed. The filtered gas is sent to flaring tower where cold flaring is done as the gas has not enough heat content.

To provide pressure to extremely low pressure wells Activation tank are used. Two test tanks for are also used along with storage tanks for storage and

testing purpose. For safety purpose, fire water tank is also present. The water tank is

connected to centrifugal pumps which increases pressure from 4kg/cm2 to 10kg/cm2

For electrical purpose a 400kv generator is also installed in GGS.

Mehsana CTF

It has oil coming from NK-CTF, Sobhasan CTF, Becharaji GGS. Oil from Mehsana CTF is displaced to Navagaon CTF and finally to Baroda Refinery.

The Mehsana CTF has

6 pumps of 400kw each. 7 storage tanks of 10000m3 each.

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2 bottom transfer tanks of 2000m3 each. Setting time is 24 hours. Water is separated only by settlement in Bottom transfer tank. It was often noted that oil from two tanks are mixed and finally water cut is

reduced to less than 2%.

Visit to DTYS (Drilling Tool Yards and Services)

Directional Drilling is performed in the following cases:

1. If the point is inaccessible.2. Land acquisition problem3. To have more production4. Salt dome encountered5. For relief wells

The deviated wells are of L,J,S profile.

From kick-off point we start deviating from the perpendicular. We lower kick off assembly to set the well in the required Azimuth. Then we use build up assembly.

Dropping Assembly: To drop angle used in S profile.

Hold Up Assembly: To hold angle.

Software used for directional drill plan- Well Path 5

Tools Present

Bit- 17 ½ “, 12 ¼ “, 8 1/2 “, 5 ½”…… Bit sub Drill Collar- 8”, 6 ½”……. Drill Pipe 5”, 3 ½”………………… Non-Magnetic Drill Collar (NMDC) Positive Displacement Motor

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Bent sub (NMDC) Kelly, Kelly saver sub, crossover sub. Tongs

Casing tongs

Drill tongs

a. Hydraulicb. Manual

Slips- Used for holding pipe Core barrel Insert TCR, Milling TCR

Fishing Tools

Impression block- Made of rubber used to get the shape of fish.

Overshot, Junk Basket, wireline spear.

Pipes: Colour Bands

Premium- Two band of white colour

2 class- One yellow band.

3 class- orange band (not in use)

Class 1 and premium are used in off-shore drilling.

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Visit to RigsDrilling services of Mehsana consists of

1. Drilling

2. Cementing

3. Mud Services

There are 7 Drilling Rigs in Mehsana. 6 mobile and one electrical (E760X1) manufactured by BHEL.

Different types of onshore rigs are there

a) Conventional: used where roads can easily be constructed. It is cheapest rig. Greater rig up and rig down time is a disadvantage.

b) Mobile: Used for shallow wells. It can drill up to 3000m. It is mounted on the truck.

c) Dessert: used in desert where roads can’t be made easily. Tyres are big and specially designed.

d) Heli: used in difficult areas where it is transported by helicopters. Transportation cost is high.

e) TBA: It means "Transported By Any means". It can be dismantled to smaller modules of 4000 to 5000 lbs and can be transported even by smaller trucks.

Offshore Rigs are classified as:

a) Jack Up or Supported Jack up used in a shallow depth of 100m.

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b) Independent leg Jack Up.

c) Mat Jack Up

ONGC has 8 Jack Up rigs and 2 Drill Ships.

d) Semi Submersible

e) Drillship: having 8 anchors

Rig E760X1 (electrical Rig)

It is a high tech well rig. It is made by BHEL. The height of rig was 144ft and the derric floor was 25 ft above the ground. It has capacity of 3000 m drilling depth.

No. of Sheaves-5

Shale shaker-2

No. of water tanks-1

Degasser-1

Gauges:

-Hook Hold Gauge

-Wireline Gauge

-Weight on bit

-SPM

-RPM

-Rotating Torque

-Pump Pressure

Mud Pumps: 2 in No. - 9'stroke, 7'line

-Spud (Bentonite) mud

-Polymer used (KCL, PHPA)

-Non Damaging, Drilling Fluid (NDDF)

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-17 lit/stroke

Hoppers: 2

Diesel Tank-1(volume-50m3)

Reserve tank 2

-Depth drilled at visit=1100m

-Estimate pay zone-1200m

Bent-1.25-1.5 degrees

I.e. for every 100ft or 30m-bent is 8-9.5

Rig IR90X1

It is a mobile drilling Rig. It has less sophisticated feature as compared to electrical rig. It can drill maximum up to 2000m depth.

During visit to the rig intermediate casing was being lowered.

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Visit to Cementing sectionCementing Services:

#Super Charge-To accelerate the suction of cement slurry.

#Cement carries has the capacity of 20 tonnes.

#There is a pumping unit.

#Gas Mixtures: It is used for homogeneous cementing of casing.

#Two agitators are being used for mixing

#100 psi pressure is used for mixing; the pressure is provided by hydraulic pump.

Cement carrier Bowl (+H2O) Mixing Unit

#Turbulent flow of cement is required.

#New truck was bought from Canada for Rs.11 crores. The mixing and pumping facility was in the same unit.

#Earlier Russian trucks had separate units for mixing and pumping.

#Truck is sent to different fields according to the requirement. The truck is of large size and sophisticated and specialized parts.

Visit to IR-II Santhal

Cementing operation was carried out for conductor casing. The Canadian truck was operating at that time. The drilling BOP was kept aside and other BOP for cementing was in use. The work was Highly Risky due to the chances of pipe bursting due to very high pressure used in cementing. Pumping was stopped only when cement came out of the annulus.

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Visit to PTYS (Sobhasan), work over section Tools observed in PTYS

#Hydraulic packer, Tension packer, mechanical packer, centralizer, bridge plug

#sucker rod

Bridge Plug: It is used to isolate zone just like packer. On rotating dye on the top opens. After that it is pulled and the $$ratchet$$ expands.

Cement Retainer: It is used in case when cementation between casing and formation is poor. It improves Cementing.

POP: Pump out Plug

Fishing Tools: The fishing tools observed were similar to that of DTYS fishing section.

RCJB: Reverse circulation junk basket.

Maintenance of tools was also done here.

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Well Services1) well completion and testing2) work over services3) down hole operations

ST-OWN THEWELL

SST-ANALYSIS THE WELL

WORK OVER

Work over has wide range of jobs.

a) Water shut off-20%

b) Zone transfer-10%

c) SRP/Gas lift section-60%

d) ED (effluent disposal) services-10%

Workover Rigs are employed for work over jobs.

Type of work over Rigs

1) Rotary Rigs: can perform rotation

2) Non Rotary Rigs: up and down movement only,(generally used for SRP)

WATER SHUT OFF (WSO)

When the water cut is increasing in the well, water shut off jobs are required.This include squeeze cementing and selective perforations.

ZONE TRANSFER23

It is used to isolate the zone with bridge plug or cement plug depending on depth.

EFFLUENT DISPOSAL (ED) WELLS

According to pollution control board a minimum depth of 1000 meter is suitable for effluent disposal. At depth greater than 1000 Mt loose sand zone is perforated according to guidance of SS. Length of perforated zone is 10-25 Mt @36 spm(shot per meter).

PMS (Preventive maintenance section)

PMS does acid fracturing if perforations are blocked by junks. If it does not work, workover services are called.

EOR (Enhanced Oil Recovery)

Well should not contain any hydrocarbon. For this chemical washing is done. The tubing and hydraulic packer are lowered by work over rig. The kill mud (NaCl) in the annulus is corrosive in nature so often after removing packer it is replaced by dichromate solution. Then packer is released again and insitu operations are carried.

WELL ABONDAMENT

When casing is damaged and well is not producing, it has to be abandoned. For it we require Work Over rig. All the perforations are choked by squeeze cementing and cement plug is placed. The top of all the casing is cut up to some meter and well is completely seal off by plate and is buried in the soil.

WORK OVER RIG (Nandasan) VISIT

NDN #84

Capacity- 50 tonnes

Rotary rig

Production started in 2007.

SRP was removed and work over was carried out.

Well was a directional well.

Production was reduced and zone transfer was done earlier. On checking it was found that the cementing job was not done properly. So during our visit the drilling was done for preparation of squeeze cementing job.

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Role of SST with reference to geological reservoir and other operation

BHS (bottom hole study), Nandasan Field

a) Sub-Surface pressure

b) Temperature

c) Pressure Gradient

d) Sampling

RDAG (Reservoir Data Accumulation Group)

This requires gathering of sub-surface data of Mehsana oil fields. Reservoir Pressure Gauge (RPG) is used for this purpose. Parts of RPG or sub-surface pressure gauge:

a) Mechanical Spring loaded clock

b) Chart Holder

C) Stylus

d) Bourdons Tube

e) Thermometer

f) Metallic Chart

Models of Sub Surface Pressure gauge:

90015

90100

90098

Function:

The metallic chart is fixed in Place and a baseline is drawn by the stylus on the metallic chart

Lubricator is separated from the well by closing Christmas tree valve.

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Sub Surface pressure gauge is lowered in the lubricator with a wireline attached to a winch. The winch is mounted on the truck.

The tool is lowered first 150 m and kept stand by to get the pressure and the pressure at that place is engraved on the metallic chart. The tool is hold for 2 min and then again lowered 100m and kept at that position for 2 min.

Metallic chart is drawn with step wise graph. After reaching the lowest depth the instrument is taken back and graph is studied.

The deflection at each depth interval is measured and then corresponding pressure is measured and then the gradient at that point is calculated.

During the visit the well was in flowing condition and shut in bottom hole pressure (SBHP) is measured.

The metallic chart is read either electronically or manually with microscope.

Pressure Gradient

0-0.1 - Gas

0.1-0.25 - Condensate

0.25-0.50 - High GOR Oil

0.50-0.80- Light Oil

0.80-0.96- Heavy Oil

Greater than 0.96- water/brine/other heavy solids

Temperature of bottom hole is measured by inbuilt thermometer present in measured by inbuilt thermometer present in the sub surface pressure gauge.

Temperature is measured while lowering the instrument.

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EchometerThis instrument is used in SRP wells where sub surface pressure gauge cannot be used to locate the level of liquid in the well. In this instrument signal is sent downwards and received after refection. The time taken for the process is noted and interpreted to find the pressure gradient at different depth of the well.

It has three components:

1. Well analyzer2. Gas cylinder3. Gas gun

VISIT TO FIELD 51-KAYAL (NANDASAN)

Working of Echometer:

Gas gun is charged with N2 using gas cylinder to a pressure of 500-600 psi

Annulus valve is opened and the gas pressure is released. The gas was accumulated in the annulus

The gun was fixed in the annulus valve/flange. Gas gun has a sensor which is connected to the computer / well analyzer. Gun is shot and the reading is received by the analyzer.

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Presentation on geology/Sub surfaceEstimation of reserve is one of the most important tasks. It is done by-

Volumetric method Application of reservoir performance technique

a. Material balanceb. Numerical simulationc. Decline curve analysis

Properties of various rocks are determined.

Pre requisite for the occurrence of reservoir is a basin

Different types of basins

1. Type craton interior basin2. Continental multi cycle basins3. Continental rift basins4. Delta basins5. Force AMC basins

Different instruments used in exploration are:

Geophones: geophones measures how much and for how long the ground moves, as in an earth quake.

Vibrator truck and vibroseis:

In old days, seismic lines were acquired using dynamite as the energy source. Today most onshore seismic data acquired using vibroseis where energy source is a giant vibrator truck.

The main job of the petroleum geologists is to search for new pools. Sub surface mapping is practical chiefly in working out the geology of the petroleum deposits.

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Different maps are:1. Structural maps and section.2. Isopath maps3. Facies maps4. Geochemical mapping5. Geophysical mapping

6. Seismic mappinga. Magnetic mappingb. Gravity mappingc. Radioactivity mapping

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Well logging operations – visit to logging sectionLog is a record of various properties vs. depth. Majority of logs are recorded while pulling out the tool.

Logging jobs:-

A) Open Hole LoggingB) Cased Hole Logging C) Production Logging

Open Hole Logging:-

1) Electrical lagging for getting the resistivity2) Spontaneous potential (sp) log for litho logy identification, estimation of shale

volume, estimation of formation water resistivity, depth correlation etc3) Gamma ray (gr) log for litho logy identification, estimation of shale volume,

depth correlation purpose either Open Hole or Cased Hole and for mapping purpose

4) Sonic log to get formation travel time from which porosity can be obtained5) Formation density log, neutron log are to get porosity 6) Dip meter log- to get dip of formation along with the direction of dip7) FMI log to indentify fractures8) DSI log to get mechanical properties of formation9) CMR log for bound water identification10) SFT/MDT/RFI to get formation fluid sample, formation pressure and to

have a qualitative idea about the permeability

In case of highly deviated and horizontal wells the conventional logging is not possible. In such cases logging is either carried out through pipe conveyed, measurement while drilling or logging while drilling.

Porosity determination from

(i) Sonic Log (Δ¿¿ t)¿

Φ=(Δ¿¿ t−Δtma)/(Δtf−Δtma )¿

Where

Δtf=189∗µs/ f , Δtma=47.4∗µs / f (lime stone)

(ii) Density Log (ρb)

Φ=( ρ¿¿ma−ρb)/(ρma−ρf )¿

Where ρf=1.09 gm/cc, ρma=2.7 gm.cc (limestone)

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CASED HOLE LOGGING OPERATIONS:-

1) CBL-VDL-CCL-GR – to find out the cement bond quality between casing-cement formation

2) USIT- ultra sonic imaging tool to find out the cement bond between casing cement formation

3) GR-CCL- For depth correlation with respect to open hole logs4) GR-TCL- For depth correlation with respect to open hole logs and it is done

through tubing 5) CHFR – Cased hole formation resistivity. It is useful where UHRL is not

available due to well complications.

PRODUCTION LOGGING OPERATIONS

1) To diagnose the well problems which includes mechanical and production problems

2) To get layer or interval wise production or injection rate3) For reservoir monitoring 4) Spinner logs are used to obtain fluid lfow rates

flow rates, Q=V X A

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