Some material avoids rapid mineralization and enters:

Operational definition

Postmortem storage fate.

The retention of organic matter in a pool whose turnover time is substantially longer than the organisms or ordinary ecological processes being considered.

Examples include:

Sequestration is relative, not necessarily permanent. A changing environment can remobilize the stored material. Postmortem change begins with loss of homeostatic control and autolysis, after which scavengers, detritivores, microbes, and abiotic processes fragment, assimilate, mineralize, respire, or sequester the remaining matter. (NCBI)