WYTCH FARM FIELD

Wytch Farm is an oil field and processing facility in Purbeck district of Dorset, England. It is the largest onshore oil field in Western Europe. It was discovered in 1973 by the Nationalised British Gas Corporation and it began operation in 1979. The field is presently operated by Perenco.

The table below shows the monthly production from the field from 1973 to 2012. The data was obtained from the Department of Energy and Climate Change, United Kingdom but was modified to include the unproductive years from 1973 and 1978. The field is expected to last until 2020.

Production in bblYear Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Yearly Total

1973 0 0 0 0 0 0 0 0 0 0 0 0 01974 0 0 0 0 0 0 0 0 0 0 0 0 01975 0 0 0 0 0 0 0 0 0 0 0 0 01976 0 0 0 0 0 0 0 0 0 0 0 0 01977 0 0 0 0 0 0 0 0 0 0 0 0 01978 0 0 0 0 0 0 0 0 0 0 0 0 01979 0 0 4,293 4,791 5,224 5,950 5,859 5,447 5,311 5,482 5,308 5,160 52,8251980 6,754 12,485 9,725 16,205 19,069 21,864 24,842 24,718 22,124 13,791 13,842 13,507 198,9261981 13,735 12,296 13,797 14,283 14,173 14,286 17,352 4,633 15,985 18,259 17,669 16,909 173,3771982 10,800 14,519 18,655 18,220 18,265 17,545 11,213 16,149 19,000 11,269 20,254 20,497 196,3861983 19,365 21,250 23,945 22,165 20,502 20,184 26,406 25,677 12,636 20,138 22,912 23,417 258,5971984 24,330 23,244 23,489 21,701 22,484 24,417 22,341 22,158 21,288 15,769 28,706 23,651 273,5781985 28,534 28,070 20,112 15,804 22,888 26,453 21,354 24,888 28,322 31,425 30,347 25,692 303,8891986 33,216 28,524 28,381 30,353 32,781 26,739 33,495 26,978 12,371 17,507 29,491 33,194 333,0301987 32,992 29,471 31,976 30,785 31,872 28,437 29,472 32,265 30,645 31,442 28,509 14,456 352,3221988 33,676 50,127 53,006 40,531 48,662 50,389 52,291 59,846 48,580 51,567 51,256 44,977 584,9081989 48,526 40,722 48,702 43,500 45,010 48,569 47,015 50,065 48,816 51,286 49,701 51,184 573,0961990 45,313 39,084 43,567 18,344 45,549 60,366 163,344 249,036 167,355 240,374 270,038 303,579 1,645,9491991 321,579 287,428 328,367 330,176 316,384 301,673 323,488 319,488 314,279 350,193 326,938 314,654 3,834,6471992 331,914 334,855 370,059 359,783 362,489 346,489 360,294 362,034 339,691 349,012 323,079 337,415 4,177,1141993 341,508 297,140 322,734 93,609 330,323 326,281 349,072 397,243 371,239 364,718 343,103 370,473 3,907,4431994 406,699 352,833 390,661 419,534 409,745 430,296 431,885 446,279 434,235 441,565 436,822 439,768 5,040,3221995 454,181 412,810 451,471 441,507 474,292 464,249 489,943 476,542 444,243 478,535 473,818 493,866 5,555,4571996 507,765 456,803 456,600 477,671 506,758 484,808 526,270 515,919 446,981 444,557 464,574 531,370 5,820,0761997 527,280 468,987 512,943 486,900 489,299 413,101 402,141 421,468 458,026 470,460 424,393 451,190 5,526,1881998 465,842 474,544 526,514 481,334 436,804 460,447 495,015 513,018 490,769 501,496 449,720 484,343 5,779,8461999 453,341 384,235 418,074 391,975 376,146 377,161 388,881 391,353 355,874 409,528 385,129 396,317 4,728,0142000 379,829 352,048 370,340 336,724 93,821 309,362 321,473 281,279 282,164 290,902 272,495 295,868 3,586,3052001 282,027 254,431 279,587 254,813 271,852 262,444 273,916 264,401 275,509 288,456 275,383 282,572 3,265,3912002 272,788 239,937 265,980 241,770 241,942 234,894 254,150 247,054 225,617 243,131 229,393 223,729 2,920,3852003 237,136 193,728 203,852 208,490 144,385 144,604 207,788 218,740 203,439 205,363 189,703 190,642 2,347,8702004 184,917 176,420 184,504 170,115 174,019 145,798 153,354 167,050 166,986 172,481 163,059 165,591 2,024,2942005 160,702 143,638 154,495 143,927 141,241 141,935 144,543 153,907 140,166 128,051 127,215 133,415 1,713,2352006 130,727 105,237 121,559 107,102 113,118 127,743 135,938 124,669 122,001 119,156 86,788 105,738 1,399,7762007 125,456 112,097 110,258 76,959 112,050 113,214 104,737 106,924 88,625 112,952 101,116 115,945 1,280,3332008 117,800 108,456 119,061 110,307 112,242 106,978 111,511 109,063 107,469 107,481 81,902 99,942 1,292,2122009 98,117 93,095 101,365 97,896 101,187 104,440 107,567 106,053 97,605 104,102 88,534 104,565 1,204,5262010 101,452 89,972 99,935 92,680 97,813 94,977 90,755 85,719 62,883 84,125 31,121 0 931,4322011 67 29,192 58,253 56,462 60,769 63,282 68,642 66,652 48,410 55,991 57,542 62,298 627,5602012 66,687 64,054 61,707 72,331 72,583 67,601 70,217 73,081 71,062 74,754 0 0 694,077

Production Profile

As explained earlier, the field was discovered in 1973. As shown in Figure 1, exploration activities were carried out between 1973 and 1978. Production started in March, 1979 with 4,293 bbl and it is expected to last till 2020.

Figure 1: Production Profile for Wytch Farm Field, between 1973 and 2012

Build -Up: The build –up stage in Wytch Farm Field is between 1979 and 1995. This is the phase of production from start to peak. It involves the drilling of development wells and upsurge of new wells. The output at this stage depends on the rate at which the wells are drilled and brought on stream, and performance of these wells as they come on stream. The speed of build -up is diminished by mechanical drilling problems and geological problems in the reservoir. Lastly, the speed of build- up is imposed by pre-drilling of wells and ensuring that early wells intersect the most productive parts of the reservoir

Plateau/Peak: The plateau or peak is between 1995 and 1998 when the field averaged about 5.8 million barrel per year.

Decline: After the peak/plateau years, the field entered the decline phase where production decreased monotonically. Output depends on the skill of the geological, reservoir and production engineers to understand the reservoir, to drill infill wells and to apply pressure maintenance and artificial lift technology

Economic limit: As time goes by, the revenue from the field will decline with production and it finally get to a stage where the field will not the profitable and wells will be abandoned. Wytch Farm is expected to last till 2020 for its oil production

https://www.og.decc.gov.uk/pprs/full_production.htm

1970 1975 1980 1985 1990 1995 2000 2005 2010 20150

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7000000

Production in Wytch Farm Field, UK

Year

Pro

du

ctio

n, b

bl

Discovery

Ap-praisal well

First oil

Build up

Peak/Plat-eau

Decline

Economic limit