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This approach can be employed most directly in the case of wood samples with many years growth present (but not able to be dated by dendrochronology), where the tree-ring series of unknown date can be compared against the similarly constructed (super 14) C calibration curve built from known-age wood.

This process of curve-fitting has come to be called "wiggle-matching." In this paper, we look at the requirements for getting good precision by this method: sequence length, sampling frequency, and measurement precision.

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We also look at 3 case studies: one a piece of wood which has been independently dendrochronologically dated, and two others of unknown age relating to archaeological activity at Silchester, UK (Roman) and Miletos, Anatolia (relating to the volcanic eruption at Thera).

The method has both advantages and limitations vis-a-vis the calibration of individual dates.

In many valleys, the thickness of ignimbrite may be 70–80 m.

The Changbaishan ignimbrite has a low aspect ratio of 1.87 × 10, respectively.

The column collapse probably was a pulsing collapse, because the ignimbrite and pumice fall deposits are interleaved. In a Plinian pumice-fall section, the grain-size of pumice is reversely graded (coarse pumice on bottom and fine pumice on top).

Machida et al.,(1990) divided the Millennium eruption into 4 stages: Baegdu Plinian pumice fall, Changbai pyroclastic flow, Yuanchi tephra falls, and Baishan pyroclastic flow. The variation of pumice size shows a major fluctuation in eruption column height during this Plinian event.Chlorine concentrations in the peralkaline from the Millennium eruption were postulated to have reached up to 2% and an average of 0.44%.The Millennium eruption was thus thought to have emitted an enormous mass of volatiles into the stratosphere, potentially resulting in a major climatic impact.The ignimbrite-forming eruption may have lasted one and a half to four days (35–104 hours), while the Plinian eruption may have lasted three to nine and a half days (77–230 hours).The total duration of the eruption may have been four and a half to fourteen days (111–333 hours).In order to compare environmental and inferred climatic change during the Preboreal in The Netherlands, five terrestrial records were analysed.

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