(Adds earnings context, Dreamworld safety comments, details on...

(Adds earnings context, Dreamworld safety comments, details on share price)

SYDNEY, Oct 27 (Reuters) - Australia's Ardent Leisure Group (ADD), the owner of an amusement park where four people were killed on a water ride this week, said on Thursday the tragedy "will have a significant impact" on the company's earnings for the remainder of the year.

Two men and two women were killed on Tuesday when they were trapped under an upturned raft on the Thunder River Rapids Ride at Dreamworld, near the Gold Coast in Queensland state. Ardent has said the ride completed an annual safety inspection less than a month ago.

"Revenue lost as a result of this tragic event will have a significant impact on EBITDA for the remainder of the year, due to the high level of fixed costs required to operate the business," Chief Executive Officer Deborah Thomas said in a speech prepared for the company's annual general meeting in Sydney. "It is not possible to provide any further guidance at this time."

In the year through June, Ardent reported an 18.7 percent rise in earnings before interest, tax, depreciation and amortisation (EBITDA), partly helped by an 8.5 percent rise in theme park EBITDA.

The company does not report its individual theme park performances, but said in August that its theme park admissions rose 13 percent in the year to end-June, lifted largely by a 36 percent spike in visitors from China.

But in the two trading sessions since the fatal accident, shares of Sydney-listed Ardent have slid 22 percent. The company issued its guidance on Thursday before the market opened.

Ardent, which holds its annual general meeting later on Thursday, has been under pressure to defend its safety practices amid suggestions it failed to follow warnings about technical problems on the ride involved in the incident.

In a separate statement on Thursday, Dreamworld said it completed an "annual mechanical and structural safety engineering inspection" on Sept. 29, four weeks earlier.

"As per regulations, this safety audit was conducted by a specialist external engineering firm," the Dreamworld statement said, adding that it would provide the results of that audit to the workplace safety investigators and other authorities.

Dreamworld has said will reopen for a memorial service on Friday. Ardent Chairman Neil Balnaves said the amusement park will reopen "as normal" the following day, although the Thunder River Rapids Ride would stay closed until the end of a coronial inquiry.