The term Anthropocene, proposed and increasingly employed to denote the current interval of anthropogenic global environmental change, may be discussed on stratigraphic grounds. A case can be made for its consideration as a formal epoch in that, since the start of the Industrial Revolution, Earth has endured changes sufficient to leave a global stratigraphic signature distinct from that of the Holocene or of previous Pleistocene interglacial phases, encompassing novel biotic, sedimentary, and geochemical change. These changes, although likely only in their initial phases, are sufficiently distinct and robustly established for suggestions of a Holocene-Anthropocene boundary in the recent historical past to be geologically reasonable. The boundary may be defined either via Global Stratigraphic Section and Point ("golden spike") locations or by adopting a numerical date. Formal adoption of this term in the near future will largely depend on its utility, particularly to earth scientists working on late Holocene successions. This datum, from the perspective of the far future, will most probably approximate a distinctive stratigraphic boundary.
The Anthropocene, an informal term used to signal the impact of collective human activity on biological, physical and chemical processes on the Earth system, is assessed using stratigraphic criteria. It is complex in time, space and process, and may be considered in terms of the scale, relative timing, duration and novelty of its various phenomena. The lithostratigraphic signal includes both direct components, such as urban constructions and man-made deposits, and indirect ones, such as sediment flux changes. Already widespread, these are producing a significant ‘event layer’, locally with considerable long-term preservation potential. Chemostratigraphic signals include new organic compounds, but are likely to be dominated by the effects of CO 2 release, particularly via acidification in the marine realm, and man-made radionuclides. The sequence stratigraphic signal is negligible to date, but may become geologically significant over centennial/millennial time scales. The rapidly growing biostratigraphic signal includes geologically novel aspects (the scale of globally transferred species) and geologically will have permanent effects.
The GSSP for the base of the Eocene Series is located at 1. 58 m above the base of Section DBH in the Dababiya Quarry, on the east bank of the Nile River, about 35 km south of Luxor, Egypt. It is the base of Bed 1 of the Dababyia Quarry Beds of the El Mahmiya Member of the Esna Formation, interpreted as having recorded the basal inflection of the carbon isotope excursion (CIE), a prominent (3 to 5%) geochemical signature which is recorded in marine (deep and shallow) and terrestrial settings around the world. The Paleocene/Eocene boundary is thus truly a globally correlatable chronostratigraphic level. It may be correlated also on the basis of 1) the mass extinction of abyssal and bathyal benthic foraminifera (Stensioina beccariiformis microfauna), and reflected at shallower depths by a minor event; 2) the transient occurrence of the excursion taxa among the planktonic foraminifera (Acarinina africana, A. sibaiyaensis, Morozovella allisonensis); 3) the transient occurrence of the Rhomboaster spp. -Discoaster araneus (RD) assemblage; 4) an acme of the dinoflagellate Apectodinium complex. The GSSP-defined Paleocene/Eocene boundary is approximately 0.8 my older than the base of the standard Eocene Series as defined by the Ypresian Stage in epicontinental northwestern Europe.
Summary Volcaniclastic deposits in sedimentary sequences of the North Sea Basin and adjacent areas indicate that two phases of early Palaeogene explosive volcanism took place in the north-eastern Atlantic region. The earlier, late Palaeocene (NP5-NP6) phase involved significant activity along a N-S trend that included both the British and Faeroe-Greenland Tertiary volcanic provinces. The later phase spanned the latest Palaeocene and early Eocene (NP9 to NP13), with much or all of the activity taking place in the Faeroe-Greenland Province. Early ashfalls of mixed basaltic to silicic compositions may have included contributions from the final phase of British volcanism, but were followed by a series of 200 or more tholeiitic ashfalls of Faeroe-Greenland provenance. These tholeiitic eruptions appear to have marked the onset of separation of Greenland from Europe in mid NP10 times. A subsequent return to pyroclastic activity of more variable compositions appears to have marked the re-establishment of stresses within the E Greenland crust that continued throughout the early Eocene (mid NP10 to end NP13). The mechanism of eruption of the tholeiitic ashes, which are equivalent to a magma volume of several thousand cubic kilometres, is uncertain, but they would appear to involve hydrovolcanic processes.
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