X I 



X 2 



X 20 



X21 



X22 



B platform 

 Storage tank 



X 7 



X6 



18X 



17 X 



A platform 



X 11 



16X 



1000 ?0J3m 



I i i 



xio 



Figure 3. An example of a sampling pattern made up of a series of transects 

 all emanating from a storage tank. These sampling stations were originally 

 used in a biological monitoring program to asses, possible effects of ballast 

 water discharged from the central storage tank in the Ekofisk oil field. Ana- 

 lytical samples were taken from these and other sampling stations after the 

 Ekofisk blowout which occurred on the B platform. This figure was adapted from 

 "Biological Monitoring of Sediments in Ekofisk Oilfield" (Addy et al. 1978). 



186 



