scholarly journals Late Eocene impact-induced climate and hydrological changes: Evidence from the Massignano global stratotype section and point (central Italy)

2009 ◽  
Author(s):  
Rodolfo Coccioni ◽  
Fabrizio Frontalini ◽  
Silvia Spezzaferri
Keyword(s):  
Central Italy ◽  
Late Eocene ◽  
Hydrological Changes ◽  
Stratotype Section

Regional to global correlation of Eocene–Oligocene boundary transition successions using biostratigraphic, geophysical and geochemical methods

2019 ◽  
Vol 157 (1) ◽  
pp. 80-100
Author(s):  
Brooks B. Ellwood ◽  
Lawrence Febo ◽  
Laurie Anderson ◽  
Rebecca T. Hackworth ◽  
Guy H. Means ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Central Italy ◽  
Geophysical Methods ◽  
Global Scale ◽  
Multiple Correlation ◽  
Southeastern Usa ◽  
Global Correlation ◽  
Extinction Event ◽  
Oxygen Stable Isotope ◽  
Stratotype Section

AbstractRegional to global high-resolution correlation and timing is critical when attempting to answer important geological questions, such as the greenhouse to icehouse transition that occurred during the Eocene–Oligocene boundary transition. Timing of these events on a global scale can only be answered using correlation among many sections, and multiple correlation proxies, including biostratigraphy, lithostratigraphy, geochemistry and geophysical methods. Here we present litho- and biostratigraphy for five successions located in the southeastern USA. To broaden the scope of correlation, we also employ carbon and oxygen stable isotope and magnetic susceptibility (χ) data to interpret these sections regionally, and correlate to the Global Boundary Stratotype Section and Point (GSSP) near Massignano in central Italy. Our results indicate that approaching the Eocene–Oligocene boundary, climate warmed slightly, but then δ18O data exhibit an abrupt c. +5 ‰ positive shift towards cooling that reached a maximum c. 1 m below the boundary at St Stephens Quarry, Alabama. This shift was accompanied by a c. −3 ‰ negative shift in δ13C interpreted to indicate environmental changes associated with the onset of the Eocene–Oligocene boundary planktonic foraminiferal extinction event. The observed cold pulse may be responsible for the final extinction of Hantkeninidae, used to define the beginning of the Rupelian Stage. Immediately preceding the boundary, Hantkeninidae species dropped significantly in abundance and size (pre-extinction dwarfing occurring before the final Eocene–Oligocene extinctions), and these changes may be the reason for inconsistencies in past Eocene–Oligocene boundary placement in the southeastern USA.

Integrated stratigraphy at the Bartonian–Priabonian transition: Correlation between shallow benthic and calcareous plankton zones (Varignano section, northern Italy)

2019 ◽  
Vol 132 (3-4) ◽  
pp. 495-520
Author(s):  
Valeria Luciani ◽  
Eliana Fornaciari ◽  
Cesare A. Papazzoni ◽  
Edoardo Dallanave ◽  
Luca Giusberti ◽  
...  
Keyword(s):  
Late Eocene ◽  
Northern Italy ◽  
Critical Interval ◽  
Larger Foraminifera ◽  
Ne Italy ◽  
First Occurrence ◽  
Calcareous Plankton ◽  
Stratotype Section ◽  
Primary Base ◽  
Zonal Boundary

Abstract The Varignano section (Trento province, northern Italy) provides an exceptional opportunity for a direct correlation between shallow benthic (SB) zones and standard calcareous plankton zones at the Bartonian–Priabonian transition (middle–late Eocene). This transition has attracted great attention by biostratigraphers in the last decades in searching for a boundary stratotype section. The Alano di Piave section (NE Italy) is the leading candidate for the base Priabonian Global Stratotype Section and Point (GSSP). However, at Alano, larger foraminifera-bearing resedimented levels occur exclusively well below the critical interval. Conversely, the Varignano section, located ∼80 km west of the Alano section, preserves several coarse bioclastic levels rich in larger foraminifera throughout the section. These levels are intercalated with basinal marlstones, crystal tuff layers, and an organic-rich interval. The Varignano section spans planktic foraminiferal Zones E10 and E11 to lower E14, calcareous nannofossil Zones MNP16Bc to MNP18 and Chrons 18n to 17n.2n. The main calcareous plankton events recently proposed as primary base-Priabonian correlation tools, i.e., the last occurrence of the genus Morozovelloides and the Base common (= acme beginning) of Cribrocentrum erbae occur, respectively, within C17n.3n and C17n.2n. We correlate prominent crystal tuff layers exposed at Varignano with those outcropping at Alano, including the Tiziano bed, whose base has also been proposed as the GSSP level. The Varignano section spans the upper SB17 and the lower SB18 Zones, with the zonal boundary marked by the first occurrence of the genus Pellatispira. This event occurs in the lower part of Zones E13 and MNP17A within C18n, well below all the potential criteria to identify the GSSP that also includes Chron C17n.1n base. We point out that the usage of shallow-water biostratigraphers in placing the base of the Priabonian at the base of Zone SB19 is inconsistent with the proposed plankton events.

Hydrological changes during the Roman Climatic Optimum in northern Tuscany (Central Italy) as evidenced by speleothem records and archaeological data

2020 ◽  
Vol 35 (6) ◽  
pp. 791-802
Author(s):  
M. Bini ◽  
G. Zanchetta ◽  
E. Regattieri ◽  
I. Isola ◽  
R. N. Drysdale ◽  
...  
Keyword(s):  
Central Italy ◽  
Archaeological Data ◽  
Hydrological Changes ◽  
Climatic Optimum

GEOTHERMAL SYSTEMS IN THE NORTHERN APENNINES, ITALY: MODERN ANALOGUES OF CARLIN-STYLE GOLD DEPOSITS

2021 ◽  
Vol 116 (7) ◽  
pp. 1491-1501
Author(s):  
Richard H. Sillitoe ◽  
Andrea Brogi
Keyword(s):  
Meteoric Water ◽  
Gold Mineralization ◽  
Central Italy ◽  
Late Eocene ◽  
Gold Deposits ◽  
Northern Apennines ◽  
Geothermal Systems ◽  
Reactive Iron ◽  
Northern Nevada ◽  
Younger Age

Abstract Carlin-type gold deposits in northern Nevada are inferred to overlie concealed late Eocene plutons, which are increasingly thought to have provided magmatic input to the meteoric water-dominated fluids from which the gold was precipitated. The Larderello, Monte Amiata, and Latera geothermal systems in the Northern Apennines of southern Tuscany and northern Latium, central Italy, may represent Pliocene to present-day analogues because of their demonstrated association with subsurface plutons and jasperoid-hosted antimony-gold mineralization. The plutons, which at depths of >5–7 km remain at least partially molten, continue to supply heat and magmatic fluids to the meteoric water-dominated geothermal systems. Formerly mined antimony deposits of Pliocene or younger age are exposed on the peripheries of the CO2 ± H2S-emitting geothermal systems, and antimony sulfides are still actively precipitating. Stibnite and submicroscopic gold in disseminated pyrite, along with Au/Ag of <0.5 and anomalous As, Hg, Tl, and Ba values, accompanied jasperoid formation in the Northern Apennines systems. Carlin-type mineralization in northern Nevada and the antimony-gold mineralization in the Northern Apennines are hosted by permeable carbonate rocks, particularly stratabound breccias, where they are intersected by steep normal or oblique-slip faults and confined beneath tectonically emplaced hydrologic seals. The Northern Apennines antimony-gold mineralization formed at shallow, epithermal depths, like that recently recognized in the southern Carlin trend of northern Nevada. Although underexplored, the Northern Apennines gold prospects are unlikely to ever attain the giant status of the Carlin-type deposits in northern Nevada, probably because of lower magmatic fertility (ilmenite-series rather than magnetite-series magmatism) and host-rock receptivity (less reactive iron). Nevertheless, shallow carbonate-rock aquifers within high-temperature, intrusion-related geothermal systems, be they extinct or still active, may be prospective for Carlin-style gold deposits.

Astronomic calibration of the late Eocene/early Oligocene Massignano section (central Italy)

2006 ◽  
Vol 7 (7) ◽  
pp. n/a-n/a ◽  
Author(s):  
Luigi Jovane ◽  
Fabio Florindo ◽  
Mario Sprovieri ◽  
Heiko Pälike
Keyword(s):  
Central Italy ◽  
Late Eocene ◽  
Early Oligocene
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