health state of personnel

2.3 concise description of contract areas

The closest settlement is the city of Alat located 60 km to the north-west. 8-10 km to the east of the deposits the settlement of Dengizkul is situated, and the district center Mubarek (Kaga-Karshi railroad) is 120 km to the east. 20 km to the south-east of the deposits Urtabulak gas field is situated.

Exploratory drilling at Khauzak-Shady was commenced in 1967. Drilling of the well 1 on Khauzak site in 1968 revealed industrial gas presence in the upper jurassic carbonate deposits. The main exploratory works in this area were finished in 1974, though supplementary exploration of its single spots continued up to 1993. In total, 20 exploratory and one observation well were drilled in Khauzak area.

Most of them (16 wells) was drilled during 1967-74 and closed down as having been fully recoved. Nowadays practically all these wells are flooded by Lake Dengizkul. Two more exploratory wells 301, 301 and one monitor well 242 were drilled in 1988-93; as of 01.10.2001 they belong to the monitor wells fund (to my opinion, they still belong to it as far as they are not in the LUKOIL balance).

Shady located to the north of Khauzak was first preliminary drilled in 1972. Industrial gas presence in the jurassic carbonate deposits was detected during the testing of the well 1 in this area in 1974, which was confirmed by the testing of the exploratory wells 2 and 3. The drilling results of the exploratory wells 4,5 and 5 and testing prospecting wells allowed concluding that Shady together with Khauzak is a single, large-scale gas-condensate deposit. In total, 8 exploratory wells were drilled at Shady. In recent years a range of seismic exploration works have been performed.

The peculiarities of geographical location of Khauzak and Shady of Dengizkul deposit are:

• 
  sites location in a desert zone, pretty distantly from human settlements;
  
• 
  no drinking water supply sources in this area;
  
• 
  Khauzak and Shady location comparatively closely to other important facilities of oil-gas industry;
  
• 
  facilities dislocation in extremely continental climatic zone;
  
• 
  location in the area with poor-developed road system and infrastructure.
  

The lower part of the horizon (XVSR) was determined as unpromising. During XVP horizon testings at Khauzak commercial gas inflow with an output from 140 to 450 thous. m³/day was produced. During XV-HP horizon testings commercial gas inflow with an output from 28 to 381 thous. m³/day was obtained. Thus, resulting from the tests, commercial gas presence was detected in ХV- Р, ХV-НР horizons. Besides, in the lower ХV-НР horizon in the south-east of Khauzak area (wells 14, 5, 12) a fissile stratigraphic equivalent of Khausak reef knolls is distinguished. Reef bed is multipay. Its size is 1.3-2.3 х 2.7-3.5 km, the height ranges within 18-12 m. GWC of the reef bed is detected at 2332 m; of the lower above-reef bed – at 2336 m. The above-reef bed is multypay-common contact, lithologically screened from the east. Bed size is 29 х 12-14 km, height 40-150 m (pictures 7 and 8).

Gas bed is covered with sulphate-halogen Kimmeridgium-Tithonian deposits, the capacity of which ranges from 200 to 506 m. Gas-water contact was detected at 2332 m. Strata pressure made up 277,3 kg/cm², temperature – 98 ^оС.

Khauzak and Shady blanket gas composition is as follows: methane – 88,15%, ethane – 1,38%, propane – 0,32%, butane – 0,17%, pentane plus – 0,52%, hydrogen sulphide – 4,25%, carbon dioxide 4.3%, nitrogen – 0,31%, density – 0.769 kg/m³. Deposits gas is methanic and dry. One cubic meter of gas contains 56,6 g of sulphur.

Deposits condensate is heavy, high-sulfur and basically is composed of benzene and kerosene fractions. By hydrocarbon group content of benzene fractions condensate is of methane-aromatic-naphthenic type (table 1).

Table 1 - Group hydrocarbon composition of stable condensate

Fractions,	Output,	Hydrocarbon content in condensate, weight in %.
оС	weight in %.	Aromatic	Naphthenic	Paraffin
Up to 60	-	-	-	-
60-95	3.8	1.0	1.7	1.1
95-122	10.8	3.1	4.9	2.8
122-150	13.0	4.5	5.3	3.2
150-200	15.1	3.3	3.0	8.8
>200	57.3	12.1	14.3	30.9
	100.0	24.0	29.2	46.8

Stratum water connected to the gas-bearing intervals has mineralization from 85 to 108 g/l within Khauzak deposits. Chloride-sodium and chloride-potassium prevail in this water. It contains high concentrations of iodine (up to 31 mg/l), bromine (up to 329 mg/l), boron oxide (not more than 102 mg/l).

The set potential condensate content is 24.3 g/m³.

Thus, the main peculiarity of these sites is high content of hydrogen sulfide and carbon dioxide in natural gases.

However, the deposits belong to complicated geological and field facilities and many parameters have to be specified. Based upon the results of production wells drilling and their operation, filtration and capacity characteristics of gas deposits and wells deliverability will be specified.