The Sleeping Beauty of instant fossilization

Asphyxiation by volcanic gases then instant fossilisation through electromagnetic transmutation processes?

Or 2 dinosaurs sleeping peacefully, not noticing a local volcano eruption when most animals seem sensitive to eruptions before they happen? Bodies not damaged and perfectly persevered with not one single sign of a death struggle?

The perfect preservation of the skeleton of both its holotype and referred specimen in a lifelike posture implies that the animals were rapidly entombed while they were still alive.

It is tentatively hypothesized that both Changmiania liaoningensis specimens were suddenly entrapped in a collapsed underground burrow while they were resting, which would explain their perfect lifelike postures and the complete absence of weathering and scavenging traces.

Vertebrate fossils unearthed from the lower Lujiatun Beds often retain a three-dimensional form, remaining perfectly articulated without any trace of weathering, scavenging or other disturbance.

Such a perfect preservation of the skeleton in a lifelike posture, as observed in both the holotype and referred specimen of Changmiania liaoningensis and also in countless fossils from the Lujiatun Beds, implies that the animals were rapidly entombed while they were still alive.

It has also been proposed that some of the most fossiliferous locations in the Yixian Formation, and particularly in the Lujiatun Beds, are the result of instant catastrophic mass mortality events preserved in tuffaceous ashes; in such a Pompeii-like scenario, the main cause of death for the vertebrates from the Lujiatun beds would have been asphyxiation by toxic volcanic gases of ashes.
A new basal ornithopod dinosaur from the Lower Cretaceous of China

asphyxiation instant fossilization fossils

They found the remains of two of the same new species, which the researchers have named Changmiania liaoningensis. Both were in nearly pristine condition. The name means "eternal sleeper" in Chinese, because both of the dinosaurs appeared to have been buried while alive with their eyes closed, looking as though they were asleep. The researchers suggest the reason for the quick demise and nearly pristine condition was likely due to a volcanic eruption catching them both as they slumbered in their burrow. The area where the dinosaurs were discovered was part of the plain that had been covered in debris from an ancient massive volcanic eruption, which had also covered many other creatures. The area is a well-known archeological dig site.

The researchers suggest that the burrows in which the dinosaurs had been sleeping likely collapsed under the weight of the debris from the volcano, giving the dinosaurs no chance to dig themselves out. They note also that the tails of the dinosaurs had been stretched out due to stiffness.
New eternal sleeper dinosaurs unearthed in China | Phys.org

Or just instant in situ preservation or transmuted chemical elements to rock?

Eternal sleepers through catastrophe?

showed that the sediments entombing a herd of juvenile Psittacosaurus skeletons from the Lujiatun Beds near Liu Tai village in western Liaoning represent a lahar (volcanic mudflow), either during the eruptive phase of a nearby volcanic center, or during a non-eruptive debris flow that reworked previously deposited volcanic material. This scenario might be extended to other exceptionally preserved specimens from the same beds, but again we lack precise stratigraphic, sedimentological and taphonomic information about those specimens as most were discovered by local farmers and most of them were heavily restored.

Gao argued that lifelike posture of vertebrate fossils from the Lujiatun beds contradicts burial in a low energy lahar at least for those specimens: even a low energy lahar is likely to move a small animal out of a perimortem position.

It has also been proposed that some of the most fossiliferous locations in the Yixian Formation, and particularly in the Lujiatun Beds, are the result of instant catastrophic mass mortality events preserved in tuffaceous ashes; in such a Pompeii-like scenario, the main cause of death for the vertebrates from the Lujiatun beds would have been asphyxiation by toxic volcanic gases of ashes.

his hypothesis implies a brief but painful agony, which is certainly not supported by the apparent peaceful posture of the Mei and Changmiania specimens. Faux & Padian (2007) suggest that death resulting from asphyxiation, toxins and infections can be reflected by an opisthotonic posture (hyperextension of the spine with both neck and tail recurved over the back) of the fossil skeleton; this posture is frequent in the two-dimensionally preserved specimens from the Jianshangou and Dawangzhangzi beds of the Yixian Formation, but is markedly different from the ‘sleeping’ dinosaurs from the Lujiatun Beds. However, Reisdorf & Wuttke (2012) interpret the opithotonic posture as a post-mortem rather than a perimortem phenomenom, depending on the varying decay resistance of the soft tissues. Gao et al. (2012) similarly show that the troodontid specimens (and also the Changmiania fossils) from the Lujiatun Beds lack the ‘pugulistic’ hyperflexion of hands and toes often observed in humans that perished in pyroclastic flows and surges at Pompeii and Herculanum, interpreted as a perimortem response to death from high temperatures and fire (Mastolorenzo et al., 2010).
A new basal ornithopod dinosaur from the Lower Cretaceous of China

Can material appear in enough volume to instantaneously bury the Dinosaurs of Mongolia? Or around the world to preserve dinosaur tracks and human footprints on paths?

There were at least three major sand accretion events comprising the Gobi desert region. The third one, the virtually lose structureless sandstone with no bedding features is the one that interred the Gobi dinosaurs. Over the years the sand cemented together to form sandstone, fossilizing the dinosaurs and other animals in the process.

Extraterrestrial Sand (and other debris) rained down almost instantaneously – probably in a matter of hours or less – a ‘sand weather bomb’ so to speak. The speed at which if fell was enough to choke and entomb all life forms virtually instantaneously.
Were the Dinosaurs of Mongolia rapidly buried by Extraterrestrial Sands? | God King Scenario