In general, the enclosure member is preferably prepared from a material which is permeable to a fluid existing in the subterranean environment or which is injected with {HEAD ~ the capsules} into {TAIL ~ the formation} 
into
In general , the enclosure member is preferably prepared from a material which is permeable to a fluid existing in the subterranean environment or which is injected with { HEAD ~ the capsules } into { TAIL ~ the formation }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL