Officials are trying to work out why jockey Simone Montgomerie was thrown from her horse and killed during a race at the Darwin Cup Carnival.

The part of the track where the accident occurred is used as a crossing by racegoers between races.

But Darwin Turf Club chairman Brett Dixon played down any speculation the condition of that stretch caused the accident and said he was awaiting the outcome of the stewards' investigation.

"Whether it's the crossing, the track being too hard, the barriers not opening properly - we treat every one of those complaints quite seriously," he told reporters in Darwin on Tuesday.

"If we thought there was an issue or the track was unsafe, I can guarantee you we would not be racing."

Mr Dixon would not comment on whether the horse Riahgrand had baulked or shied in the race on Monday before throwing Ms Montgomerie, who was trampled by the rest of the field.

He also would not say whether it was the way the sand track at the Fannie Bay Racecourse had been raked that possibly alarmed the horse.

"We rake every time before a race at that crossing; whether that spooked the horse or not, I can't tell you," he said.

Ms Montgomerie is the first rider to be killed in a Darwin race fall, and this is the first time the Cup has been cancelled.

She leaves behind her partner Brendon Davis, also a jockey, and a five-year-old daughter Kodah.

"This has really rocked (us)," Mr Dixon said.

"We're doing everything we possibly can to help those that have been disadvantaged as a result of this event."

Mr Dixon announced on Tuesday that the $200,000 prize money from the abandoned Darwin Cup would be donated to a fund the club set up to support her family.

Cup sponsors Carlton United Breweries and Lincoln Jenkins have also donated $50,000 to the fund, which has been matched by the Northern Territory government.

Riahgrand's trainer Gary Clarke said it took a long time to find a person of Montgomerie's calibre.

"Simone was a gem of a person," Clarke told the ABC.

"She was a super hard worker, dedicated to her work, to her family, her young daughter.

"She's going to be sadly missed."

Ms Montgomerie's death takes the number of jockeys killed in Australia to 502, according to the National Jockeys Trust.

"Jockeys are just gutted," said trust general manager Tony Crisafi.

"They know how dangerous it is. You should be able to go to work every day and come home (safely)."