ir ▁field ▁or , ▁more ▁specifically , ▁Sar ir ▁C ▁is ▁on ▁west ▁edge ▁of ▁the ▁Cal ans cio ▁Sand ▁Sea ▁at ▁the ▁sout heast ▁margin ▁of ▁the ▁Sir te ▁Bas in . ▁Sar ir ▁C , ▁which ▁is ▁part ▁of ▁a ▁three - field ▁complex , ▁is ▁ 5 6   km ▁long ▁and ▁ 4 0   km ▁wide ▁covering ▁ 3 7 8   km ². ▁To ▁its ▁north ▁is ▁Sar ir ▁L , ▁covering ▁. ▁Situ ated ▁between ▁the ▁two ▁is ▁a ▁much ▁smaller ▁Sar ir ▁North ▁pool . ▁Est im ated ▁ult imate ▁oil ▁recovery ▁from ▁Sar ir ▁L ▁is ▁. ▁ ▁Pre - Dis cover y ▁In ▁ 1 9 5 7 , ▁the ▁Lib yan ▁government ▁granted ▁Con cess ion ▁ 6 5 ▁to ▁B unker ▁H unt , ▁an ▁independent ▁oil ▁producer ▁from ▁Texas . ▁By ▁ 1 9 6 0 , ▁B P ▁had ▁assumed ▁a ▁ 5 0 % ▁interest ▁in ▁C - 6 5 ▁and ▁became ▁the ▁operator . ▁After ▁large ▁discover ies ▁in ▁the ▁Sir te ▁Bas in ▁in ▁ 1 9 5 8 ▁and ▁ 1 9 5 9 , ▁a ▁reflection ▁se ism ology ▁survey ▁was ▁conducted ▁on ▁C - 6 5 , ▁followed ▁by ▁an ▁aer om agnet ic ▁survey ▁showing ▁the ▁existence ▁of ▁large ▁structures . ▁Later ▁that ▁year , ▁B P ▁began ▁dr illing ▁in ▁C - 6 5 , ▁ 8 0 , ▁and ▁ 8 1 , ▁target ing ▁Pale oc ene ▁and ▁C