Oil / Gas Condensate Well Stimulation for Enhancing Oil and Natural Gas Recovery - field application

.Region of fracturing Volga region (Tatarstan), Russia Krasnodarsky Territory, Russia Krasnodarsky Territory, Russia Krasnodarsky Territory, Russia Western Ciberia (Sugut), Russia Western Ciberia (Langepas), Russia Western Ciberia (Langepas), Russia Western Siberia(Nizhnevartovsk) Russia
Well product Oil Gas Gas and gas condensate Gas and gas condensate Oil Oil Oil Oil
Formation type Siltstone Terrigene (low permeable sands and claystones) Fractured limestone Sand and clay Poor oil saturated sands and aleurolite (interbedding) Terrigenous Terrigenous Terrigenous
Porosity, % 24 16 8 13 19.6 17-25 17 -
Permeability, md 479 30-40 0.5-30 1-5 0.005 - - -
Reservoir temperature, 0C 23 144 170 130 74 60 78 73
Reservoir pressure before fracturing, MPa 9,2 5,0 50,0 (на 06.1996 г.) 23,2 24,6 19,2 18,3 22,0
Perforation interval, m 1163,6-1166,0 3324-3338 5064-5117 (Packer: 4920 m.) 3002-3015;
2981-2988;
2958-2965
2440,8-2445,5;
2449,8-2450,4;
2454,0-2454,4;
2459,4-2462,0;
2463,2-2463,8
1968,8-1974,2 1821-1830;
1833-1840
2328-2332;
2335-2337
Distance between pay bed and aquifer, m 8,2 5,0 - - 81 30 25 1,2
Date of well operation starting 11.1984 06.1973 02.1988 04.1969 Beginning of well test after drilling (22.11.1999) 1981 Was drilled in 1980 06.1982
Well output (oil) before fracturing, m3/d (date) 1,8 (11.1998.) 0,0 (04.2000) 10000 nm3/d (13.09.1999) 0,0* (10.1997) 4.0 at dynamic level 749 m 0,0* (did not work) 0,0 (since 1985) 0,0 (23.05.1991)
Well output after fracturing, m3/d (date) Around 9 (1.08.2000 ) Max around 7000 nm3/(04.2000 ) 36000 nm3/d Ц max (12.05.2000) Around 40000 nm3/d (max) and around 1,5 m3/d condensate (08.1999) Over 6 m3/d (at dynamic level of liquid 995 m) Oil gusher, then about 5,0 (02.01.1998) Around 5,8 (26.04.1998 ) 9,0 (4.06.1991)
Oil density, g/m3. Content of asphaltenes, resins and paraffin, % wt. 0,93, around 35,0 . - - - 0.796 (at reservoir temperature of 13 0C 0,870 0,874 0,873
Remarks 1. Output is related to the initial stage of well completion after fracturing (swabbing). Water in oil is observed periodically. The well is under completion. (During 2 days fracturing works were carried out on 2 well close by geological parameters.)
2. Maximum achieved oil output was 24 m3/d at zero initial output (South Ural)
The well under operation. 1. Fracturing works were not complete (by CustomТs reasons)
2. The well is under operation (fracturing works is planned to be go on)
* The well was abandoned, i.e. excluded from the well stock. 1. The target of fracturing was to reduce well completion time after drilling. At a moment of fracturing the intervals 2449.8-2450.4 and 2454.0-2454.4 did not yield oil.
2. By the CustomТs reasons the fracturing works were completed only to 30 % of a design value.
1. *) During the preparation to capital repair of the well bottom hole zone was sealed with heavy mud.
2. At the initial stage after fracturing there was uncontrolled oil flow (for this reason the well was temporarily set
The well was dry (there was no even water output). Since 1985 the well was exploratory and since 1989 was under compression.Well drowning accounted for 70 %. During 34 days of the well completion 126 tons of oil were produced. 1. Before performing the offered fracturing technology the formation was treated with injection method at 56.0 MPa, acid-acetone treatment and powder gases. However, there was no oil.
2. After fracturing the well had been working during 6,5 years with an output of from 16.1 to 1.1 m3/d. A total oil production amounted to 9000 tons.
3. Propping agent УparapantФ was not used during fracturing works.


Samotlor

Samotlorskoye Field. Well No. 32605. Cluster 1962
After the HF technology application in April 1992.




Samotlor

Samotlorskoye Field. Well No. 6893. Cluster 1619
After the HF technology application in September 1991.