hit pay dirt

English Journal 10月号にディスカバリーチャンネルで放映されたドキュメンタリーの紹介があり、その中に覚えたい表現がありました。
Narrator: After hours of searching, Chief Schwager <B>hits pay dirt</B>. Greg May's car has turned up abondand in a parking lot in Aurora, Illinois, a suburb of Chicago, some 14.5 miles from Bellevue.
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"<B>hits pay dirt</B>" がその表現ですが、は注があり、幸運な発見をする、有望な手掛かりを見つける　★pay dirtは「有望な鉱脈、掘り出し物」の意、となっていました。
これだけでは芸がないので、一応英英辞書での説明も調べます。
・McGraw-Hill Dictionary of American Idioms and Phrasal Verbs:
1. Fig. to discover something of value. (Alludes to discovering valuable ore.) Sally tried a number of different jobs until she <B>hit pay dirt</B>. I tried to borrow money from a lot of different people. They all said no. Then when I went to the bank, I <B>hit pay dirt</B>.
2. Fig. to get great riches. After years of poverty, the writer <B>hit pay dirt</B> with his third novel. Jane's doing well. She really <B>hit pay dirt</B> with her new business.
・Cambridge Dictionary of American Idioms: <B>hit pay dirt</B> also <B>strike pay dirt</B>: to succeed He <B>hit pay dirt</B> with his next movie, which grossed $270 million worldwide. Etymology: based on the literal meaning of <B>pay dirt</B> (dirt that contains valuable metals)
"<B>strike pay dirt</B>" とも言えるのですね。いずれにしても鉱脈を探り当てる努力が必要なようです。