(S (S (BASENP (PRP It)) (VP (VBZ has) (VP (VBN caused) (NP (BASENP (DT an) (NN oil) (NN slick)) (ADJP (ADJP (BASENP (QP (RB about) (NN nine)) (NNS miles)) (JJ long)) (CC and) (ADJP (BASENP (NN thirty) (NNS yards)) (JJ wide))))))) (PERIOD .))