Should Raw Earth Be Improved? An Environmental Assessment
As the authors of this paper say:
Compressed earth blocks behave like a concrete of moderately poor environmen-tal and mechanical performance. Self-compacting clay concrete is close to the worst - in environmental terms - ordinary concrete for-mulations. Stabilized rammed earth and mud bricks have extremely poor environmental performances, with a CO2 intensity index about ten times worse than the average concrete values. The conclusion of this analysis is clear. Stabilization of raw earth with Portland cement is not advisable, neither in mechanical nor in environmental terms. It provides very moderate benefits while using large volume of binders.
So the conclusion is "improving" earth with high emitting binders creates more problems than it solves.