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June 29 (Reuters) - Oil and gas company Matador Resources MTDR.N said on Monday its midstream joint venture San Mateo Midstream has agreed to acquire the operating subsidiaries of Cardinal Midstream Partners for $752 million in cash.

The deal underscores continued consolidation in the U.S. energy sector as producers and midstream operators build scale and expand infrastructure to support rising shale output and growing liquefied natural gas export demand.

Cardinal's assets include a cryogenic natural gas processing complex in Loving County, Texas, with a designed inlet capacity of about 320 million cubic feet of natural gas per day and roughly 145 miles of natural gas gathering pipelines across West Texas and southern Eddy County, New Mexico.

The assets are located in the Delaware Basin, a key U.S. shale producing region.

Matador acquired 5,154 net undeveloped acres in the core of the Delaware Basin in southeast New Mexico for about $1.1 billion in May, strengthening its position in the region and in the prolific shale play.

The latest transaction, which is expected to close on or before July 31, is expected to increase San Mateo's processing capacity to more than 1 billion cubic feet per day and expand its gathering system to over 800 miles of pipeline, while also adding new third-party customers.

San Mateo Midstream, Matador's 51%-owned midstream joint venture with private equity firm Five Point Infrastructure, expects to finance the acquisition, in part, through a new term loan of up to $650 million under its existing credit facility.