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For each well including the new planned well:
The local slot coordinates relative to the site centre
15.56 ft N
(Note these must be in the clients preferred North Reference) Any deviation of TVD origin above (or below) site drill floor Current Magnetic Vector at site (for inclusion in drawings only)
1.41 ft E
0 ft
50017 nT @ 70.19 o Dip Angle -7.76 o Declination
Magnetic Field Date Magnetic Field Model
27th July 2009 BGGM 2009
*If IFR data is to be used then the Magnetic Vector relevant to each hole section must be identified.
25.3 The Existing Well Data Including Survey Tools and Depth Ranges
Any missing data within the drilling range of the new well constitutes a serious safety hazard. Whilst the legal responsibility for the completeness and quality of a survey database rests with the asset owner, in practice, many operators do not have a formal survey focal point with responsibility for this. It is imperative that all steps be taken to ensure the quality and completeness of the data before the well is planned and this should be formally agreed in writing with the operator and included in any new proposals.
The required data includes the surveys and the detail of the individual tool runs in each survey leg, for example:
Notes on the treatment of vertical wells: 1. f ny “inclination only” su ys
p ofh d bs hy b s n dw h h ncln onssetto0.00 fo h n “ ncl n on only” su y. A common error is to enter the actual inclination whilst leaving the azimuth set to 0.00. This erroneously enters a well that has been drilled due north and creates a false impression that a safe clearance exists passing to the south side of h “ c l” w ll. 2. If the vertical well has been surveyed by “ ncl n on only” h n w ll planners should assume the vertical well can deviate 50 feet per thousand in any direction as the safety envelope for planning around this “ c l” well. 3. Wh n ‘ c l’ w ll w h “inclination only” su ys cons u s high collision risk a recommended practice is to enter the “w ll” at least six times into the database. This should be done by entering the actual inclinations (in six successive wells) first with azimuths of 0°, then another with azimuths of 60°, and then additional wells at azimuths of 120°, 180°, 240° and 270° succ ss ly o c n ‘E ff l ow ’ of poss bl loc ons of h c l w ll. h w ll pl nn s’ nd d c on l d ll s’ sof w c n h n conduc n - collision scans against these dummy wellbores.
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