Martinson age dating and the orbital theory

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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.By removing the tectonic uplift effect, a sea-level curve for the past 400000 years is obtained.On this curve, the calculated elevations (m, in relation to the present sea-level), the isotopic substages and the ages (in ka=thousands of years) of the events 1 through 10, detected in Sinai, are: (1) substage: 1.1, age: 6 ka, elevation: 0.5(±0.2); (2) 2.2, 18 ka,-122(±10);(3) 4.2, 64 ka,-65 (±3); (4) 5.1, 79 ka, 0.3(±1); (5) 5.2, 91 ka,-28(±5); (6) 5.3, 99 ka,-1.5(±1); (7) 5.4, 111 ka,-29(±5); (8) 5.5, 124 ka, 6.5(±2); (9) 7.1, 193 ka,-1.4(±2); and event (10) substage: 9.3, age: 331 ka, elevation: 2.9(±2).A review is given of the science-based techniques that have been used to establish archaeological chronologies from the million-year range down to the historical period.

based on the regional teetonics of southern Sinai, and assuming a sea-level of 6.5 m above the present sea-level during the last interglacial high stand (substage 5.5), an average uplift rate of 0.085 mm/year is estimated.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.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.

In 2010 the Subcommission on Quaternary Stratigraphy of the International Commission on Stratigraphy dropped other lists of MIS dates and started using the Lisiecki & Raymo (2005) LR04 Benthic Stack, as updated.

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