| dc.description.abstract | Permeability has been calculated for three exploration wells from the “Smørbukk” field, from the mid – Norwegian Sea. Permeability from logs, cores and cross plots have been derived and compared with permeability from well testing.
Permeability from logs alone is derived by the Timur’s correlation. It is observed that this permeability is affected by the shape of the well. Timur’s correlation is based on porosity and water saturation, porosity has been calculated from density log which is easily affected by the shape of well. And the constants in the correlation must be corrected for each formation to give a good match.
Permeability from cores, gives a good overview of the permeability distribution in the cored interval, but is difficult to scale up for the un – cored interval. The Arithmetic scaling gives much higher values than the geometric method. Gas slippage (Klinkenberg effect) has also been discussed, this effect leads to wrong (higher) permeability and must be corrected for at low pressures.
Test
Top
Bottom
K DST
K Arith
K geom
6406/2-1
DST 7
4427
4495
0,03
0,05
0,44
DST 6
4645
4704
4,2
16,62
0,61
DST 5
4816
4858
3,2
5,89
0,43
DST 4
4910
4924
4,0
0,94
0,76
DST 3
5021
5041
0,49
1,45
1,06
DST 2
5099
5170
6,5
8,515
0,67
DST 1
5201
5227
0,29
0,41
0,98
6406/2-2
DST 2
4714
4745
15
56,40
1,62
DST 1
4868
4927
0,7
9,18
1,59
6406/2-4SR
DST 2
4684
4704
0,07
4,02
0,95
DST 1
4874
4904
16,1
26,8
1,71
Permeability from cross plot gives a good overview of permeability distribution, as seen from the result. The best permeability is from well testing; the effective permeability of the tested interval is calculated. All effects are counted for in the permeability, as seen in the literature study, minerals and overburden pressure reduces the permeability. | no_NO |
