ABSTRACT: The Geological Society of London Proposal for “â€¦ending the distinction between the dual stratigraphic terminology of time-rock units (of chronostratigraphy) and geologic time units (of geochronology). The long held, but widely misunderstood distinction between these two essentially parallel time scales has been rendered unnecessary by the adoption of the global stratotype sections and points (GSSP-golden spike) principle in defining intervals of geologic time within rock strata.â€ Our review of stratigraphic principles, concepts, models and paradigms through history clearly shows that the GSL Proposal is flawed and if adopted will be of disservice to the stratigraphic community. We recommend the continued use of the dual stratigraphic terminology of chronostratigraphy and geochronology for the following reasons: (1) time-rock (chronostratigraphic) and geologic time (geochronologic) units are conceptually different; (2) the subtended time-rock’s unit space between its “golden spiked-markedâ€ lower and upper boundaries, actually corresponds to the duration of the time-rock unit’s defining geologic s.l. events-set; therefore, in no way can physical time (instants or intervals) be directly defined by GSSPs, (3) combining in a single system of “chronostratigraphic unitsâ€ the time-rock and geologic time units as currently understood, leads to the epistemological error of uniting evidence (rock successions) with inference (the interpreted duration of chosen defining events); (4) the redundancy of the terms eonothem, erathem, system, series, and stage with eon, era, period, epoch and age lacks support, given that they are conceptually different; in fact, referring to “eon,â€ “era,â€ etc. as terms uniting both time-rock and geochronologic connotations will produce needless nomenclatorial confusion, attaching different meanings to already well known and widely used geologic terms; and (5) the reversion of ‘geochronology’ to its main stream and original meaning of numerical dating has no foundation, just by considering that the use of geochronolgy precedes numerical dating, which became practical by the 1960’s. We endorse the following: (1) the GSSP network needs to be improved through the use of reference sections at high latitude sites, and in sedimentary continental rock successions of achievable, dependable positioning in the global standard timetable; and (2) to attend to researchers using astronomically-forced sedimentary systems, the designation of unit stratotypes needs to be reinstated as a valid and as a, complementary means of defining chronostratigraphic units, particularly at the stage and lower chronostratigraphic rank.
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