What: Shares of Corenergy Infrastructure Trust Inc (CORR) were under pressure today, after the company announced an asset acquisition from Energy XXI Ltd (NASDAQ: EXXI). Under the terms of the deal, Corenergy agreed to pay $245 million in cash for Energy XXI's Grand Isle Gathering System, or GIGS, which is a subsea, midstream pipeline system for offshore oilfields in the Gulf of Mexico. Further, as a result of the deal, Corenergy announced that it will raise its annualized dividend rate from $0.54 to $0.60 per share.

So what: GIGS is a critical infrastructure asset supporting oil production from seven fields in the gulf, six of which are operated by Energy XXI and one by ExxonMobil (XOM 0.57%). As a result of this transaction, Energy XXI will continue to operate the system, which it will lease from Corenergy under a long-term triple-net lease. That lease contains minimum rent plus variable rent, with an annual minimum rent payment of $40.5 million.

It's the type of asset that Corenergy wants to own, as it's an ideal fit within its REIT structure. Further, unlike its last deal, this one is very accretive to its dividend, which is increasing as soon as the deal closes.

Now what: While the acquisition looks solid on the surface, there are two reasons investors are selling off the stock. First, this is a very large deal for Corenergy, as its current enterprise value is just over $400 million. As such, this one asset will represent a big part of its portfolio. Further, Energy XXI is a financially stressed energy company, which is why it needed to sell this asset to raise cash in the first place. Because of its weak financial condition, there's a risk that it might not be able to make its minimum rent payments if the oil market were to weaken materially. That said, the deal is expected to pay big dividends for Corenergy's investors, as long as everything goes according to plan.