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Porous Formation A Formation can be damaged mainly while one of following activities (ordered in timely manner). 1) During Drilling and Completions 2) During and after production and workover operations 3) During Injection  Formation Damage Mechanisms: 2) During  and after production and workover operations. (This is part 2 of this topic, for part one of this topic click here .) This kind of formation damage is divided into following types. 1) Due to increase in relative permeability of fluid other than desired fluid. 2) Due to viscosity increase 3) Due to precipitations. 3) Formation Damage Due to precipitations: Main precipitation problems on field during production: 1) Inorganic scales, 2)  Precipitation related to acidizing In stimulation jobs ( Sludge formation) , 3)  Paraffin 4)  Asphaltene We have aqueous formation water is already present inside reservoir rock pores along with oil, and during Workover or other activities, when other fluid enter into formation, which is not comp

A Formation can be damaged mainly while one of following activities (ordered in timely manner). 1) During Drilling and Completions  (click to see) 2) During and after production and workover operations 3) During Injection  Formation Damage Mechanisms: 2) During  and after production and workover operations. This kind of formation damage is divided into following types. 1) Due to increase in relative permeability of fluid other than desired fluid. 2) Due to viscosity increase 3) Due to precipitations. 1) Due to increase in relative permeability of  fluid other than desired fluid: Imagine, you are left with 1 GB of internet with your plan and you are sharing it with your friend with help of wifi. You are surfing at your normal speed, but your new friend is watching movie online What will happen ? You will be not able to surf more time ?  Same thing happened in reservoir also. We want more oil flow for More time, but other fluids (water, gas) block path of oil flow and results into less o

Image referred from Internet What is basic difference between Workover, Well intervention and Well stimulation ? Work over is operations of repair and maintenance of well which requires Work over rig or drilling rig or hydraulic work over units. So, it is term used to describe heavy well maintenance or repairing works. X mas tree is removed and BOP is installed for workover or well service processes. It is not performed on live wells.(well needs to be killed to perform work over operations) Work over operations : 1) Water shutt off 2) Gas shutt off 3) Servicing 4) Fishing  5) Recompeltion 4) Layer transfer 5) Profile modification in injection wells 6) Well deepening 7) Side tracking 8) Long drift side track (LDST) 9) Short drift side track (SDST) 10) Well abandonment and Plugging Well interventions is term, which is used to describe operations, which doesn't involve rig. So, it is Rigless operation. So, it is term used for, light duty works of well repair and maintenance. It is pe

Formation Damage  Part 1 Definition: Formation damage is impairment or resistance to fluid flow from or to Reservoir (Formation) near the wellbore area.(vicinity of wellbore). So, it’s a process . If formation is damaged, we cannot produce or inject fluid at predicted or desired rate. Formation can be damaged mainly while one of following activities (ordered in timely manner). 1) During Drilling and Completions 2) During and after production and workover operations 3) During Injection   Formation Damage Mechanisms: 1)  During Drilling and Completions We start from drilling activities which result into formation damage. First is Selection of Drilling fluids and its effects. Drilling fluids are part and heart system of Drilling activities.  When drilling fluids come into contact with Formation, many changes occurs to reservoir rock and to fluid also (here two different things are going to get into contact, so its natural to happen something). Whole drilling fluid is unable to go into for