For the first time in over a decade, most of the Big Oil players replaced less than 100% of their reserves. While the low price of oil definitely played a part, the sheer size of the oil giants also factored into their decision to slow down.

In this clip from the Industry Focus: Energy podcast, Motley Fool analysts Sean O'Reilly and Tyler Crowe explain why it's so expensive for big companies to replace their reserves, and how ExxonMobil (NYSE:XOM) is looking to make a deal with Italian integrated oil company Eni S.p.A. (NYSE:E) to mitigate these difficulties. 

A transcript follows the video.

This podcast was recorded on March 31, 2016.

Sean O'Reilly: Does this low replacement rate and lack of investment have anything to do with the recent rumors that ExxonMobil is looking to bid on, for lack of a better term, some huge reserves?

Tyler Crowe: It's certainly part of it. I mean, when you're looking at how expensive it is to explore for new oil, especially for a big oil company who has to go hunting -- they have to go hunting with an elephant gun versus a slingshot, if they want to replace their reserves. They're not like a Whiting Petroleum or somebody like who's just trying to replace 150,000 or 160,000 barrels per day. We're talking about a company that needs to replace 4.1 million barrels per day. And so, when you need to move the needle that much, you need big, big exploration expenses, which normally means going offshore, and going to places where we haven't really found oil yet. And that's going to cost a lot of money.

At the same time, there is an opportunity here with other companies that are struggling for cash that need a little bit of help, and have some lucrative assets, but no way of developing them. This is the case right now, where ExxonMobil is looking at some assets from the Italian integrated oil company Eni S.p.A. They have some very attractive assets off the coast of Mozambique that's looking in the trillions and trillions of cubic feet of natural gas. It's probably one of the largest finds of natural gas that we've had in the last 5-10 years. They're also looking at some of their very lucrative assets in North Africa, such as Egypt and things like that.

O'Reilly: I was just about to ask, you said it's Eni?

Crowe: Yeah.

O'Reilly: Was it them that I read that found a huge gas field in the Mediterranean off the coast of Israel?

Crowe: No, they found a large one off of Egypt.

O'Reilly: OK.

Crowe: It's kind of in the same area--

O'Reilly: It's kind of catty-corner there, between... yeah.

Crowe: Yeah. So, there are some large gas fields off of Israel, Noble Energy for the U.S., they're on the Israel side, basically because they're the only company in the U.S. that doesn't have any ties to the Middle East, so they can operate with Israel, versus everyone else who's kind of been dabbling on the Egyptian side of the border, or, territorial boundary on that offshore area. And they're finding some very large natural gas deposits.