Back in 2004, my brother applied for oil and gas jobs on the internet ( I couldn't remember the company). About 1 week or 2 weeks later, the company sent a mail to my brother and the mail looked really professional; they wrote it on hard paper with professional looking address and contact info.

They told my brother that he was approved for the job and must pay about US$300 - US$500 (I couldn't remember); but luckily for him I made thorough research about the company and they turned out to be a complete scam!

My advice is do not pay for money when you're applying for oil and gas jobs; usually oil and gas job companies do not ask for money to process job application. Because they have a lot of money.