Dipartimento di Scienze della Terra

 

PRINCIPAL INVESTIGATOR: Luca ALDEGA
TITLE: Deciphering the timing of deformation of polyphase faults in fold-and-thrust belts: Insights from K-Ar dating of clay gouges and U-Pb of calcite veins 
FUNDING AGENCY: Sapienza Università di Roma

START DATE: Febbraio 2019
END DATE: Febbraio 2022
ABSTRACT:
We apply for funding to run an innovative research initiative aiming at a quantum leap in the Apennines and Iberian Chain knowledge by addressing, by means of a novel multidisciplinary approach, two different, but fully complementary, research targets. The proposed activities will improve our fundamental multiscalar understanding of the dynamic evolution of the belts and potential impact thereof on society. By studying carefully-selected, geological transects across- and along strike the Apennines and the Iberian Chain, this research project will address the: (1) deformation style in space and through time between continuum and discretized/episodic, possibly seismic, deformation and (2) analysis of the time relationships among thrust-sheet emplacement, internal deformation by folding and extensional tectonics and the study of the rates of the controlling processes. The project will implement a completely novel and integrated scientific approach based on the combination of multiscalar structural analysis with dating of low temperature deformation episodes. We aim to measure the timing and rates (within a detailed structural framework) of the processes that have steered the nucleation and growth of the belt by K-Ar dating fine-grained synkinematic clay minerals formed authigenically in brittle and brittle-ductile fault rocks and those processes that have triggered the orogenic extension by U-Pb analysis of synkinematic calcite. The outcome will be the improvement of the existing and only loosely time-constrained model of the Apennines and Iberian chain nucleation and development by adding tight constraints on the exact temporal dimension involved in buildup and subsequent tearing down of the orogen. Numerical modeling will aid the final synthesis of the project, where results will be collated to constrain the long-term tectonic evolution of the orogens in space and through time.

 

PRINCIPAL INVESTIGATOR: Luca ALDEGA
TITLE: Obduction of ophiolites in the Alpine-Himalayan belt: a regional comparison via a multidisciplinary approach
FUNDING AGENCY: Sapienza Università di Roma

START DATE: novembre 2019
END DATE: novembre 2021
ABSTRACT:
The best worldwide examples of obducted ophiolite sequences occur along the Alpine-Himalayan belt in Italy (Northern Apennines), in Cyprus (Troodos ophiolite) and in Oman (Semail ophiolite). Despite the fact that these Ophiolite sheets belong to the same orogenic belt, they were not so far compared. We propose to compare quantitatively for the first time these three areas concerning the following aspects: thickness of obducted ophiolite sheets; thermal evolution of sub-ophiolite rocks; structural level at which obduction processes occurred; tectonic structures that accommodated ophiolite obduction and unroofing of sub-ophiolite rocks; nature and temperature of fluids involved during faulting; timing and duration of obduction and exhumation processes. To do this, we propose a multidisciplinary study based on stratigraphic and structural field geology, geochemical laboratory analyses (clumped isotopes), fluid inclusions on calcite veins, mixed layers illite-smectite (I-S) paleothermal indicators, paleomagnetic analyses and U-Pb datings.
The following research objectives will be pursued: 1) the lateral variation of the thickness of ophiolite sheets will be constrained by paleothermal analysis of sub-ophiolite rocks; 2) the structural level at which obduction processes occurred will be constrained via paleothermal analysis of sub-ophiolite rocks and via analysis (clumped isotopes and fluid inclusions on syn-kinematic calcite veins associated with faults) of fossil fluids which permeated fault zones; 3) the tectonic structures that accommodated ophiolite obduction and exhumation of sub-ophiolite rocks will be constrained by field and laboratory structural analyses and by paleomagnetic analysis on sub ophiolite rocks; 4) the age and duration of obduction and exhumation processes will be constrained by U-Pb datings of syn-tectonic calcite veins; 5) we will finally propose evolutionary models for ophiolite obduction in the investigated areas.

 

PRINCIPAL INVESTIGATOR: Luca ALDEGA
TITLE: Constraining rates and mechanisms of vertical movements of orogenic belts in space and through time by thermal and geochronological evolution of sedimentary successions and fault rocks
FUNDING AGENCY: Sapienza Università di Roma

START DATE: Dicembre 2020
END DATE: Dicembre 2023
ABSTRACT:
This research initiative aims at improving our fundamental multiscalar understanding of the dynamic evolution of orogenic belts from rifting to shortening and late orogenic extension. By studying carefully selected key areas of the Apennines, northern Calabria and Oman Mountains, this project will address the: 1) definition of burial and exhumation paths in space and time; 2) deformation style (continuum vs. episodic, and possibly seismic deformation); 3) analysis of the time relationships among thrust-sheet emplacement, internal deformation by folding and extensional tectonics and the study of the rates of the controlling processes.
The project will implement a completely novel scientific approach based on the combination of multiscalar stratigraphic and structural analysis with the study of thermal and thermochronological evolution of sedimentary units and dating of low-temperature deformation episodes. We aim at measuring the timing and rates of the processes that have steered the nucleation and growth of the belts, by K-Ar dating of fine-grained synkinematic clay minerals formed in brittle and brittle-ductile fault rocks and by X-ray diffraction of mixed layered minerals formed during burial. We further aim at investigating the processes that triggered orogenic extension by U-Pb analysis of synkinematic calcite and U-Th/He and fission track analysis of apatite crystals dispersed in sediments. We expect to improve significantly the existing and only loosely time-constrained models of nucleation and development of the Apennines and Oman Mountains by adding tight constraints on the exact temporal dimension involved in buildup and subsequent tearing down of the orogens. Numerical modeling will aid the final synthesis of the project, where results will be collated to constrain the long-term tectonic evolution of the orogens in space and time. A fine understanding of orogen dynamics will help us to better assess hydrogeological and seismic risk in the Italian region.

 

PRINCIPAL INVESTIGATOR: Marco BRANDANO
TITLE: The C-isotope record of anthropogenic CO₂ in the Mediterranean Holocene bioclastic interval: a possible analogy with PETM (Paleocene-Eocene Thermal Maximum)?
FUNDING AGENCY: Sapienza Università di Roma (Progetto SEED-PNR)

START DATE: Gennaio 2022
END DATE: Gennaio 2025
ABSTRACT: Anthropogenic CO₂ emissions are strongly influencing the current climate change. The C released into the atmosphere is increased from 2454 Pg in 1959 to 9897 Pg in 2015. Planet Earth has experienced several episodes of significant CO₂ emissions, the event known as PETM (Paleocene-Eocene Thermal Maximum) is an example. During the PETM, 12300 Pg of C were released into the atmosphere in a very short interval (20Ky), producing an 8 ° warming of the ocean. These large C emissions from methane and mantle CO₂ produced a strong negative excursion of the ¹³C / ¹²C ratio (δ¹³C). Similarly, since the industrial revolution, CO₂ emissions from the use of fossil fuels have produced a progressive decrease in the δ¹³C of atmospheric CO₂ from - 6.5 ‰ to the current value of approximately - 8 ‰. This decrease was recorded by the carbonate shells of marine biota, which can be an excellent tool for monitoring the trend of CO₂ released into the atmosphere. However, most of them only live a few decades. This research intends to analyze a sedimentary succession deposited on the seafloor consisting of bioclastic sediments starting from the upper Holocene. Consequently it will be possible to analyse a much longer time interval that allows to observe the trends of CO₂ emissions over the last 4000 years. The goal of this project is to use carbon isotopes to reconstruct the long-term influence of CO₂ emissions. We therefore intend to elaborate a curve of δ¹³C for the upper Holocene (4.2 ka BP) to evaluate the extent of the isotopic excursion of C produced by the anthropogenic action. The signal will be compared with that of the PETM to verify whether the current CO₂ emissions are comparable to those occurring during this well-known thermal event.

 

PRINCIPAL INVESTIGATOR: Francesco CHIOCCI
TITLE: MARENDOGAS project. Geochemical, biological, and geological characterization of shallow-water sites related to active endogenic gas emissions (Tyrrhenian Sea).
FUNDING AGENCY: Sapienza  - progetti di Ateneo -Grandi

START DATE: febbraio 2019
END DATE: dicembre 2022
ABSTRACT:
The Tyrrhenian Sea is characterised by many active features created by fluid escapes from the seafloor, linked to the tectonic evolution of this back-arc basin and the associated Apennine thrust belt. In particular, various CO₂ emissions are located in active and quiescent volcanic areas (Campi Flegrei, Ischia, Palinuro Seamount, Pontine, and EolianArchipelagos), only one site with CH₄ emissions is reported in the Tyrrhenian Sea at high depths offshore Calabria.
MARENDOGAS project aims to study a recently discovered shallow water site (Scoglio d¿Africa, Tuscan Archipelago) characterized by active CH₄ emissions, and to compare it with well-known shallow-water CO₂ dominated sites (i.e. Panarea). These sites are similar enough to be compared (shallow-water,climate, easy access for sampling and monitoring, occurrence of Posidonia oceanica meadows) but different enough (CO₂ vs CH₄, depressed areas versus mounds) to show contrast in geochemistry, mineralogy, sedimentary structures and impact on fauna.
The CO₂ emissions have been studied extensively in terms of their impact on chemical and biological systems, and as sites to test monitoring equipment. In particular, the site offshore Panarea Island was studied within the European Community funded CCS project ECO2 (http://www.eco2-project.eu/) and ECCSEL (www.eccsel.org) and was subsequently transformed into an ERIC laboratory. Our long-term goal is to propose the Scoglio d’Africa site as a natural laboratory, if it will be proved to be appealing enough to deserve it. 
In fact, opposite the CO₂ sites, knowledge regarding CH₄ seeps is very limited, with few sites in shallow water worldwide, thus numerous scientific issues warrant study. These include, but are not restricted to, the origin and the conduits of the leaking CH₄ (given that the majority of Tyrrhenian sites leak CO₂), the impact of the CH₄ on the surrounding ecosystems, and the quantification of the release CH₄ (a strong greenhouse gas) directly to the atmosphere.

 

PRINCIPAL INVESTIGATOR: Francesco CHIOCCI
TITLE: Laboratorio in situ a Scoglio d’Africa
FUNDING AGENCY: Sapienza Dip. Scienze della Terra - Progetto Dipartimento di Eccellenza

START DATE: ottobre 2019
END DATE: ottobre 2021 
ABSTRACT:
The aim is to establish of a natural scientific and educational laboratory at the Scoglio d'Affrica, an area of extreme interest both for the submarine geological features (mud volcanoes, pockmarks) and for the presence of an extensive Posidonia meadow with varying degrees of disturbance due (probably) to fluid seepages. We intend to perform geochemical monitoring activities, detailed morphological studies, stratigraphic reconstructions and dating of mud volcano eruption events, analyses on microfauna and on the relationship between fluid emissions and Posidonia meadows.
Didactically, the laboratory could be used for fields by master students in geological and natural sciences (as well as doctoral students), having shallow water diving skills, and would become a laboratory analyses that may over time build a database of georeferenced interdisciplinary data, which allow the integrated global analysis of geological structures related to fluid seepage.

 

PRINCIPAL INVESTIGATOR: Massimo SANTANTONIO
TITLE: Evoluzione tettonica Giurassica e ambienti sedimentari e geodinamici a confronto in aree-campione ai margini di tre placche: Europea
(Sila Greca), Africana (Sicilia occidentale) e Apula (Appennino centro-settentrionale).
FUNDING AGENCY: Ateneo

START DATE: 2019
END DATE:
ABSTRACT:
Calabria, Sicily, and the Umbria-Marche and Sabina Apennines display styles of extension during the Early Jurassic rift phase, which can be contrasted based on recent advances in research across these regions. These structural differences also resulted in differences
in the development and geometries of the pelagic and clastic deposits which characterize the network of basins and structural highs of each continental-margin tract. Jurassic Calabria was part of a vast high of the Hercynian basement, also including the Sardinia-Corsica
block, made of metamorphic and intrusive Paleozoic rocks. Here the rift faults coud locally have a marked oblique-slip component, which resulted in the sequestering of clastic sediments within geographically isolated compartments. In the Apennines, the pattern of
synsedimentary faults was dictated over by the existence of very thick Upper Jurassic salt, which acted as a shallow (in the Early Jurassic) detachment layer and was instrumental in producing a dense network of small structural highs and narrow basins. In Western
Sicily (Trapanese and Sciacca Domains), basaltic volcanism accompanied the stretching of the African Plate.