While the dramatic changes to Kaikōura's landscape were immediately clear after November's 7.8 quake, what happened below sea level has been as clear as mud - until now.
A new NIWA survey of the underwater landslips has shown the extraordinary changes to the canyon, some of which are three times the size of the one which continues to block the road north of Kaikōura.
It also appears to have wiped out all signs of life from the sea floor which had, until the quake, been teeming with creatures and was known as a biodiversity hotspot.
Scientists have visited the site twice since the November 14 quake, finding an extraordinary amount of mud and debris sent into the canyon's central channel.
The canyon itself has remained intact, but it is now a barren wilderness. It is thought such events only happen every few hundred years.
It is a stark contrast from a landmark survey in 2006, which helped the area gain recognition as an important marine reserve.
At the time, the canyon was home to one of the highest volumes of organisms living in mud anywhere in the world.
"It was about 100 times higher than anything reported anywhere else for that kind of seabed," NIWA marine ecologist Dr Dave Bowden says.
But now, nothing.
"We surveyed exactly the same area we did in 2006 and, while fish were still found in the area, this time we didn't record evidence of a single organism living on or in the seabed over a stretch of nearly six kilometres of seabed. Nothing. It was quite sobering, and a catastrophic event for the ecology of the canyon."
What was once dotted with burrows, tracks, pits and mounds made by seabed animals is now "smooth and barren".
He told The AM Show they're the "uncharismatic things" people wouldn't normally see - such as worms and sea cucumbers - but they're an important part of the ecosystem.
Dr Bowden says while there are still fish and whales in the area, what the new lay of the land means for predators is unknown.
However, he remained optimistic, saying he'd be "highly surprised" if life does not return and watching that process will provide scientists with valuable information given such large-scale events are so rare.
"This is a perfectly natural event. It's not the first time this has happened and it's not the last time it'll happen so something about this kind of event is probably important to the whole system, so maybe that's part of the reason why we're seeing such a big biomass of animals in the seabed there is because these kinds of events resets things," Dr Bowden told The AM Show.
There were also stark changes to the canyon rim compared to just a few years ago.
NIWA marine biologist Dr Joshu Mountjoy says mapping done in January showed the force of the earthquake.
"In 2013 everything at the head of the canyon was smooth and draped in mud. Our new data shows that the earthquake resulted in a huge slipping event. Almost every part of the upper slope had mud removed from it."
It has exposed features of the upper slope, revealing far more detail with once mud-filled valleys and ridges now cleared.
Shortly after the earthquake, NIWA noticed a huge current in the area - it is now thought those landslides were the cause.
Closer to the surface, the movement of the earth raised the seabed by nearly two metres, exposing tens of thousands of paua.
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Ministry for Primary Industries (MPI) science manager Dr Shelton Harley says it is important to understand how what's happened to the canyon has affected the food chain.
"There are few people who weren't shocked by the photos of exposed paua beds along the coast, but we know that there are other potential less obvious impacts that we need to understand."
But in perhaps some good news, a preliminary analysis of data shows the likelihood of a damaging tsunami resulting from an earthquake hasn't changed. In fact, it could actually be lower than previously thought.
MPI has created a $2 million emergency research package for the Kaikōura region which covers the effects on rock lobster, paua, blue cod, sperm whales, fur seals, Hutton's shearwaters, and intertidal and subtidal rocky reef animals and seaweeds.
Newshub.
