form of tubular sandscreens 12 for reducing inflow of solid particles and a plurality of tubular bodies 14 as is shown in fig1 the screens 12 and the tubular bodies are arranged in alternating order in the horizontal wellbore section 4 each tubular body 14 is provided with a series of outlet ports 16 of relatively small diameter for injection of fluid into the reservoir zone 2 a of the earth formation 2 as discussed hereinbefore outlet ports of this type are referred to as limited entry perforations lep which limit the flow rate of injection fluid into a zone at a given injection pressure by virtue of the fact that the velocity of injection fluid exiting the outlet ports approaches the sonic velocity the outlet ports 16 of a series are regularly spaced in circumferential direction of the tubular body 14 the sandscreens 12 are of conventional type including a perforated base pipe not shown and a tubular filter layer 13 extending around the perforated base pipe the base pipe of each sandscreen 12 is connected to the respective tubular bodies 14 adjacent the base pipe by conventional screw connectors not shown or by any other suitable means for example by welding the wellbore 1 is further provided with a production conduit 18 for the transportation of produced hydrocarbon fluid through the wellbore 1 to surface the conduit 18 having an inlet opening 19 near the upper end of the liner 8 and an injection conduit in the form of a coiled tubing 20 for the injection of injection.