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Modified by Alan E. Taylor from the scheme of Dr. Alan M. Jessop
The attached scheme is a hierarchic structure for organizing temperature data from deep permafrost wells along with the associated metadata. This is based on the scheme developed in 1996 by Dr. Alan M. Jessop for the digital Canadian Geothermal Database.
The primary file is the SITE FILE, giving location and other data pertinent to the site. This data does not change between various measurements made on a site or well. In digital form, these files have filenames such as S123-4, where the "S" indicates a site file, and the "123-4" refers to site number 123, subsite 4 (i.e. borehole 4 at site 123).
The secondary file is the LOG FILE, identifying by dates the set of temperature measurements undertaken on the well specified in the SITE file. These files contain details (dates, accuracies) of each log. In digital form, these have filenames such as L123-4.
The tertiary files are the OBSERVATION FILES, giving the actual measurements or observations taken, at the site specified in the SITE file and on the dates specified in the LOG file. While Jessop's scheme has a variety of observation files, for the purposes of CAPS, only temperature files (in digital form filenames such as T123-4), site topography file (TOP123-4) and site description file (D123-4) are provided. These, respectively, give the temperature observations at that site, a digital topography (as available) and general site description (as available). All sites have at least a temperature file. Other Observation files may be added later.
The GSC file numbers (e.g. 123) are keys to the database. Maps (Figures 1-9) and Table 1 facilitate locating sites of interest. A user then need only to note the site number (e.g. 123) and get the Sxxx file, Lxxx and Txxx files (and other files that may be available).
The following describes the data presented and their format in each of the file sets described above: Formats used for the "Canadian Geothermal Data Collection - Deep permafrost temperatures and thickness of permafrost" database
(modified from scheme of Dr. A.M. Jessop, 1996)
________________________________________________________ Quantity format first length column SITE FILE....................................................... Line 1: Site number NNNNN 1 5 Well number NN 7 2 Site name 48A 10 48 Industry name 48A 59 48 Latitude NNN-NN.N 114 8 Longitude NNNN-NN.N 123 9 UTM NN NNNNNN NNNNNN (not used) Location accuracy NNNN (m) (not used) Ground elev'n ASL NNNNNN (m) 169 6 KB above ground NNN (m) 176 3 Total Depth TD (gnd)NNNNNN (m) 180 6 Date of drill start yymmdd 187 6 Date drilling end yymmdd 194 6 Date well abandonmt yymmdd 201 6 LOG FILE........................................................ Site number NNNNN 1 5 Well number NN 7 2 Log number NNN 10 3 Type of log16A14 16 Date of log yymmdd 31 6 Depth accuracy N.NN 38 4 Units (m or %) A 43 1 Temp. accuracy N.NN 45 4 Comments 100A 50 100 .....Note that this format allows many logs per site, each identified with a date, etc. TEMPERATURE FILE................................................ Site number NNNNN 1 5 Well number NN 7 2 Log number NNN 10 3 Measured depth NNNN.N (m) 14 6 Vertical depth NNNN.N (m) 21 6 Temperature NNN.NNN (oC) 28 7 .....Note that this format accommodates many logs on various dates (key the "log number" to the LOG file for date).
SITE TOPOGRAPHY FILE.....(FIRST LINE)...........................
(N.B. Parameters here are those used in the "Topo correction" known to terrestrial heat flow researchers; these parameters construct a rough digital topography surrounding the well. See, Jaeger, J.C., 1965. Application of the theory of heat conduction to geothermal measurements. In, W.H.K. Lee, ed., Terrestrial heat flow, Geophysical monograph series vol. 8, AGU, Washington, DC. NOTE THAT THIS FILE CONSISTS OF A "FIRST LINE" AND "SUBSEQUENT LINES"...
Site number NNNNN 1 5 Well number NN 7 2 Log number NNN 10 3 Increment of radius NNNN.N (m) 14 6 Inc'mt of elevation NNNN.N (m) 21 6 Inc'mt of azimuth NNN (degrees) 28 3 Collar height above datum NNNN.N (m) 32 6 Measured thermal gradient N.NNNN (mK/m) 39 6 Lapse rate N.NNNN (mK/m) 46 6 Collar temperature NNN.NN (oC) 53 6 (note change) Water temperature NNN.NN (oC) 60 6 Age of water body NNN.N (kyear) 66 5
SITE TOPOGRAPHY FILE.....(SUBSEQUENT LINES AS NEEDED)...........
Site number NNNNN 1 5 Well number NN 7 2 Log number NNN 10 3 Azimuth NNN (degrees) 14 3 Starting radius increment NNN (increments) 18 3 Elevation data 25 per line b,NN.N (x25 inc'mt) 26 125
SITE DESCRIPTION FILE...........................................
Site number NNNNN 1 5 Well number NN 7 2 Site description 140A 11 140 (as many lines as needed)
N.B. This file can contain any information or description that does not seem to fit elsewhere (e.g. metadata).