Perhaps the oil and gas industry didn’t get the memo about how the ongoing U.S. debt ceiling crisis and government shutdown are threatening a resurgent M&A market. At least that’s the way it looks given the trio of major energy deals announced Thursday that yielded roles for a half-dozen Am Law 100 firms.

Vinson & Elkins took the lead on two of those transactions, advising PVR Partners on its $5.6 billion sale to rival natural gas pipeline operator Regency Energy Partners, and Crestwood Midstream Partners on its $750 million acquisition of Arrow Midstream Holdings.

In the day’s third deal, Houston-based pipeline operator Buckeye Partners announced its $850 million acquisition of the East Coast oil terminals and storage tanks business of struggling oil company Hess Corp.

New York–based Hess has been busy shedding assets in recent months, with Kirkland & Ellis handling its first-ever assignment for the company in July by advising on the $1 billion sale of an energy marketing business to Centrica, according to our previous reports.

This time around, Hess stuck with its longtime outside lawyers at White & Case for counsel on the deal with Buckeye. John Reiss, global head of M&A at White & Case, and M&A partner Gregory Pryor are leading a team from the firm working on the transaction. Reiss is a former colleague of Hess general counsel Timothy Goodell—the two used to cohead the M&A group at White & Case. (Goodell is the brother of NFL commissioner Roger Goodell and son of late U.S. Senator Charles Goodell.)

Morgan, Lewis & Bockius corporate partners Benjamin Wills and Howard Meyers are advising Buckeye along with associate Morgan McDevitt. The firm has previously handled work for Buckeye, whose general counsel is Todd Russo. Fellow attorney Joseph LaSala serves as an independent director of Buckeye’s general partner.

The deal—which is expected to close before year’s end—will see Buckeye take control of 19 Hess liquid petroleum product terminals in the eastern U.S. and one on the Caribbean island of St. Lucia. (Hess remains one of the largest oil producers in North Dakota’s Bakken shale, which has made the state a popular place for lawyers, itinerant workers, and members of the world’s oldest profession.)

It was a search for more shale that led Houston-based pipeline company Crestwood to acquire oil and gas gathering systems operator Arrow Midstream. The deal, which is expected to close in the fourth quarter of this year, will allow Crestwood to expand its own footprint in the Bakken region, which last month saw DLA Piper advise Houston-based Oasis Petroleum on its $1.5 billion purchase of properties in the Williston Basin.

Vinson M&A partner Christopher Collins and capital markets partner Gillian Hobson are leading a team from the firm advising Crestwood on its acquisition of Tulsa-based Arrow Midstream. Other Vinson lawyers working on the deal include antitrust partner Neil Imus, labor and employment partner Sean Becker, employee benefits partner Shane Tucker, tax partners John Lynch and David Peck, environmental counsel Larry Pechacek, real estate counsel Harold Taylor, and associates Christie Alcala, Robert Jacobson, Emily Malandra, Igor Norinsky, Brian Polley, Paul Saputo, and Jared Whalen.

Earlier this year, Vinson advised gas pipeline and energy services company Ingery on its merger with Crestwood, according to our previous reports.

Legal advisers for privately held Arrow Midstream weren’t available by the time of this story.

Meanwhile, another Vinson team led by capital markets partners Michael Swidler and Michael Rosenwasser are advising PVR—formerly known as Penn Virginia Resources Partners—on its proposed $5.6 billion sale to Regency, a Dallas-based energy partnership. The duo are being assisted by Vinson capital markets partners John Johnston and Rachel Packer, tax partners L. Price Manford and Gary Huffman, employee benefits partner David D’Alessandro, and associates Ryan Carney, Jacobson, and Melissa Spohn.

Bruce Davis Jr. serves as general counsel of Radnor, Pennsylvania–based PVR, whose chairman is former Morgan Lewis partner Edward Cloues II. Former Hunton & Williams attorney James Gardner serves as an independent director of PVR’s general partner.

The deal, which includes the assumption of $1.8 billion in PVR debt, will help Regency push into the Marcellus and Utica shale fields. The transaction is expected to close in the first quarter of 2014.

Neel Lemon, head of the corporate department in the Dallas office of Baker Botts, is representing Regency on the matter. Other Baker Botts lawyers working on the deal include corporate partners M. Breen Haire and Joshua Davidson, tax partner Stephen Marcus, employee benefits partner J. Rob Fowler, antitrust partner Paul Cuomo, environmental partner J. Scott Janoe, finance partners Douglass Rayburn and Luke Weedon, and associates A.J. Ericksen and Daniel Gottschalk.

Former Haynes and Boone partner Paul Jolas serves as Regency’s chief legal officer. Earlier this year Regency turned to Akin Gump Strauss Hauer & Feld and Locke Lord for counsel on its $1.5 billion cash-and-stock buy of Southern Union Gathering, according to our previous reports.