Antropozenoa: "Urre koloreko iltze"-aren bila

Abstract

Antropozeno hitzak, gizakia, Holozeno Epokaren aurreko dinamika naturalak aldatzeko gai eta indar geologiko erabakigarri bihurtu den denbora tarte geologikoari egiten dio erreferentzia. 2009az geroztik, Antropozenoko lantaldea Antropozenoa ikuspegi geologikotik definitzen zentratu da, Estratigrafiari buruzko Nazioarteko Batzordeak ezarritako arauak jarraituz eta, hortaz, zer unitate kronoestratigrafikoa, beheko mugaren adina eta haren markatzaile estratigrafiko nagusiak adierazten dituzten proposamenak eginez. Erradionuklido artifizialek (137Cs, 241Am, 239Pu, 240Pu) potentzial handia eskaintzen dutela dirudi, ingurunean sinkronikoki agertzen direlako 1950 inguruko “Great Acceleration” prozesuaren ondorioz. Hala eta guztiz ere, oraindik azterketa sakonagoak behar dira denbora geologiko hau formalizatzeko behar diren irizpide estratigrafiko guztiak betetzen dituen GSSP egokia aurkitzeko. Lan honen helburua Antropozenoko lantaldearen jarduera, Antropozeno kontzeptua egituratzen duten eztabaida-elementu nagusiak eta orain arte lortutako ondorio nagusiak laburbiltzea da.; The term Anthropocene refers to the geological time interval in which humans have become a significant geological force capable of altering the previous relatively stable natural dynamics of the Holocene Epoch. Since 2009 the Anthropocene Working Group has been focused on defining the Anthropocene from a geological point of view, following the standards established by the International Commission on Stratigraphy and, thus, proposing what type of chronostratigraphic unit it represents, the age of the lower boundary and its main stratigraphic indicators. Artificial radionuclides (137Cs, 241Am, 239Pu, 240Pu) appear to offer great potential owing to their synchronous onset in the environment, coinciding approximately with the “Great Acceleration” of about 1950. However, more in-depth studies are still needed to find the appropriate GSSP that meets all the necessary stratigraphic criteria to formalize this geological time. This work is intended to summarize the activity of the Anthropocene Working Group, the main elements of discussion that vertebrate the Anthropocene concept and the main conclusions reached so far.