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In 1957 Emiliani moved to the University of Miami to have access to core-drilling ships and equipment, and began to drill in the Caribbean and collect core data.A numeric system for referring to "horizons" (events rather than periods) may also be used, with for example MIS 5.5 representing the peak point of MIS 5e, and 5.51, 5.52 etc.representing the peaks and troughs of the record at a still more detailed level.Indeed, that the MIS data matched Milankovich's theory, which he formed during World War I, so well was a key factor in the theory gaining general acceptance, despite some remaining problems at certain points, notably the so-called 100,000-year problem.For relatively recent periods data from radiocarbon dating and dendrochronology also support the MIS data.

The sediments also acquire depositional remanent magnetization which allows them to be correlated with earth's geomagnetic reversals.

For older core samples, individual annual depositions cannot usually be distinguished, and dating is taken from the geomagnetic information in the cores.

Other information, especially as to the ratios of gases such as carbon dioxide in the atmosphere, is provided by analysis of ice cores.

The SPECMAP Project, funded by the US National Science Foundation, has produced one standard chronology for oxygen isotope records, although there are others.

Over 100 stages have been identified, going currently back some 6 million years, and the scale may in future reach back up to 15 mya.

Some stages, in particular MIS 5, are divided into sub-stages, such as "MIS 5a", with 5 a, c, and e being warm and b and d cold.

Currently a number of methods are making additional detail possible.

Matching the stages to named periods proceeds as new dates are discovered and new regions are explored geologically.