APPENDIX 4 - Drilling Activity

APPENDIX 4 - Drilling Activity

(A) Offshore exploration drilling (1) : exploration wells started in each geographical area

	1991	1992	1993	1994		1995	1996	1997	1998	1999	2000
East of England	22	15	14	21⁽¹⁾	Southern N Sea	12⁽²⁾	12	16	12	3	3
East of Scotland	54⁽¹⁾	42⁽¹⁾	24	20⁽¹⁾	Central N Sea⁽⁵⁾	24⁽⁵⁾	31⁽¹⁾	24⁽²⁾	17⁽²⁾	10⁽¹⁾	11⁽²⁾
East of Shetland	16	10⁽¹⁾	5⁽¹⁾	5	Northern N Sea	4	13⁽²⁾	13⁽²⁾	10⁽²⁾	1⁽¹⁾	6⁽¹⁾
West of England/Wales	8	7	5	8	West of England/Wales	5	8	2	2	-	-
West of Shetland⁽³⁾	5	-	2	8⁽¹⁾	West of Shetland	14	7	6	6	2	6
Channel/SW Approaches	2	-	1	-	Channel/SW Approaches	1	1	-	-	-	-
Total all areas⁽²⁾	107⁽¹⁾	74⁽²⁾	51⁽¹⁾	62⁽³⁾		60⁽⁷⁾	72⁽³⁾	61⁽²⁾	47⁽⁴⁾	16⁽²⁾	26⁽³⁾

(B) Offshore appraisal drilling⁽¹⁾: appraisal wells started in each geographical area

	1991	1992	1993	1994		1995	1996	1997	1998	1999	2000
East of England	11⁽¹⁾	9⁽³⁾	9⁽¹⁾	12⁽⁴⁾	Southern N Sea	12⁽⁵⁾	4	9⁽⁴⁾	2⁽¹⁾	5⁽²⁾	3
East of Scotland	43⁽¹¹⁾	31⁽⁶⁾	41⁽⁹⁾	11⁽²⁾	Central N Sea⁽⁵⁾	16⁽⁶⁾	16⁽²⁾	9⁽¹⁾	14⁽⁶⁾	11	11⁽¹⁾
East of Shetland	18⁽⁷⁾	7⁽²⁾	5⁽²⁾	5⁽³⁾	Northern N Sea	1⁽¹⁾	14⁽²⁾	14⁽⁶⁾	17⁽¹⁰⁾	4⁽¹⁾	16⁽⁹⁾
West of England/Wales	3	2⁽¹⁾	4	1	West of England/Wales	-	2⁽¹⁾	-	-	-	1
West of Shetland⁽³⁾	4	8⁽⁴⁾	-	8⁽¹⁾	West of Shetland	9	4⁽²⁾	3⁽¹⁾	-	-	2⁽¹⁾
Channel/ SW Approaches	-	-	-	-	Channel/ SW Approaches	-	-	-	-	-	-
Total all areas⁽²⁾	79⁽¹⁹⁾	57⁽¹⁶⁾	59⁽¹²⁾	37⁽¹⁰⁾		38⁽¹²⁾	40⁽⁷⁾	35⁽¹²⁾	33⁽¹⁷⁾	20⁽³⁾	33⁽¹¹⁾

(C) Offshore development drilling⁽¹⁾:development wells started in each geographical area

	1991	1992	1993	1994		1995	1996	1997	1998	1999	2000
East of England	40⁽²⁾	47⁽⁴⁾	27⁽³⁾	39⁽¹¹⁾	Southern N Sea	39⁽⁸⁾	13⁽⁵⁾	20⁽⁶⁾	30⁽¹²⁾	35⁽¹⁷⁾	29⁽¹²⁾
East of Scotland	60⁽⁹⁾	79⁽¹²⁾	58⁽¹¹⁾	88⁽¹⁹⁾	Central N Sea⁽⁵⁾	110⁽¹⁸⁾	104⁽²⁵⁾	100⁽³⁶⁾	105⁽³⁰⁾	92⁽⁴⁴⁾	66⁽²⁴⁾
East of Shetland	41⁽⁸⁾	37⁽¹¹⁾	71⁽¹⁴⁾	67⁽¹⁷⁾	Northern N Sea	78⁽¹⁴⁾	117⁽³⁴⁾	129⁽³³⁾	120⁽⁴³⁾	82⁽²⁵⁾	103⁽³⁶⁾
West of England/Wales	3	4	6	7⁽¹⁾	West of England/Wales	13⁽²⁾	14⁽²⁾	1⁽¹⁾	3⁽¹⁾	8⁽³⁾	8⁽²⁾
West of Shetland⁽³⁾	-	-	-	1	West of Shetland	4	13⁽²⁾	7⁽²⁾	18⁽¹⁾	13⁽³⁾	10⁽⁷⁾
Total all areas⁽²⁾	144⁽¹⁹⁾	167⁽²⁷⁾	162⁽²⁸⁾	202⁽⁴⁸⁾		244⁽⁴²⁾	261⁽⁶⁸⁾	257⁽⁷⁸⁾	281⁽⁸⁹⁾	225⁽⁹⁰⁾	216⁽⁸¹⁾

(D) Onshore drilling: numbers of wells drilled

	1991	1992	1993	1994		1995	1996	1997	1998	1999	2000
Exploration	11	6	2	3	Exploration	2	6	12⁽²⁾	5	6	8
Appraisal	-	-	-	-	Appraisal	-	1	2⁽²⁾	9⁽⁴⁾	2⁽¹⁾	6
Development	3	8	9	13	Development	19	28	26⁽⁹⁾	21⁽¹³⁾	11⁽⁵⁾	11⁽⁶⁾
Total⁽²⁾	14	14	11	16		21	35	40⁽¹³⁾	35⁽¹⁷⁾	19⁽⁶⁾	25⁽⁶⁾

(1) Sidetracked wells are shown in brackets. Sidetrack wells are only counted where the intent was to acquire new geological data (sidetracks drilled due to mechanical problems with the original well are not counted).

(2) From 1988, the first figure is the total number of wells including the number of geological sidetracks. The actual number of geological sidetracks included in the total is the second figure shown in brackets. Previously published figures have been amended.

(3) �West of Shetland� includes �West of Scotland�.

(4) The figures for offshore activity are no longer collated by geographical area as has been done in past years. The tables and diagrams from 1995 reflect the geological approach to grouping wells broadly by sedimentary basin area, as described in Chapter 2. The major areas of change are the outer Moray Firth which is now partly included in the Northern North Sea rather than �East of Scotland�, and the Central North Sea which was previously split between �East of Scotland� and �East of England�: the figures for these areas are thus not directly comparable with previous years. DTI database definitions of the Geological Basins are currently based on Quadrant/Block criteria.

(5) Central North Sea includes inner and most of the outer Moray Firth areas.

NB The year in which a well is drilled is determined by its start date.

Appendix 5