Page 1. Late Quaternary landscape evolution of the Tiber River delta plain (Central Italy): new e... more Page 1. Late Quaternary landscape evolution of the Tiber River delta plain (Central Italy): new evidence from pollen data, biostratigraphy and 14C dating by ... Hier akkumulierte der Ti-ber ein Delta, das lange Zeit eine regressive Tendenz zeigte. ...
A new x-ray diffraction procedure for the determination of cristobalite in the presence of amorph... more A new x-ray diffraction procedure for the determination of cristobalite in the presence of amorphous silica is described. The standards are obtained by deposition of thin layers of watery suspensions of cristobalite and amorphous silica mixtures on silver or lead disks or cellulosa filters. Six calibration curves are then calculated to reduce weight and sampling errors. Six mcg of cristobalite mixed with 594 mcg of amorphus silica is the lowest detectable limit. The method may be used for the analysis of both raw materials and respirable dust.
Mineralogical and sedimentological features of conglomeratic bed, founded in the “minor basin” of... more Mineralogical and sedimentological features of conglomeratic bed, founded in the “minor basin” of Tagliacozzo, are described in this paper. The conglomeratic bed have been displaced in the emipelagic clay, by a debris flow flowing, into the basin, from NW to SE. This bed is a carbonatic elements of the Calcari a Briozoi e Litotamni Formation; extrabacinal clasts, probably deriving from a fragment of Thirrhenic Alpine Chaine (Alvarez, 1976), are characterized by fragments of metamorphic, volcanic and sedimentary rocks. The depositional environment of the conglomeratic bed and emipelagic clay is porbably the base of Continental slope.
Il sistema di calcolo degli indici statistici secondo FOLK & WARD (1957) viene da trenta ... more Il sistema di calcolo degli indici statistici secondo FOLK & WARD (1957) viene da trenta anni quasi universalmente utilizzato per il confronto delle distribuzioni granulometriche relative ai sedimenti incoerenti. Le semplificazioni insite nella risoluzione grafica di passaggi matematici di notevole complessità superano dì gran lunga gli effetti deleteri dell'imprecisione relativa alla trasposizione grafica dei dati. Per questo motivo ancora oggi, pur in presenza di mezzi di calcolo di notevole potenza che permetterebbero una rapidissima e ben più precisa elaborazione dei dati granulometrici attraverso il metodo dei momenti matematici, nella gran parte dei casi si continua ad utilizzare il metodo grafico, anche per la facilità di confronto dei dati così ottenuti con quelli archiviati negli anni precedenti con lo stesso metodo, Lo scrivente, dopo essersi occupato in precedenti lavori di fornire una scala di valutazione relativa agli indici statistici ottenuti con il metodo dei momenti matematici, con il presente articolo intende mettere a disposizione anche di chi utilizza il metodo grafico le facilitazioni proprie finora di chi, adottando il metodo dei momenti matematici poteva utilizzare moderni sistemi di calcolo con rapidità di elaborazione, ripetitività dei risultati e quasi totale assenza di errori accidentali.
Sono esposti i risultati della trattazione matematica della dinamica delle particelle in sediment... more Sono esposti i risultati della trattazione matematica della dinamica delle particelle in sedimentazione durante prelievi in aria. Viene evidenziata l’influenza della durata del prelievo e delle caratteristiche granulometriche degli inquinanti sulla zona volumica che li contiene, con particolare riferimento alla massima altezza di prelevamento. Si presuppone che il mezzo in cui le particelle sedimentano sia in quiete. Summary . The results of the mathematical treatment about the dynamics of the sedimenting particles during the drawings occurring in the air are reported. It is also stressed the influence of the drawing length and of the grain-size characteristics of the polluting agents on them, referring in particular to the drawing maximum height. It is supposed that the medium in which the particles fall is at rest.
In the last years, the great development of the computer programs is going to reach the geologica... more In the last years, the great development of the computer programs is going to reach the geological stratigraphical field. As a matter of fact, very powerful programs, which leave more to the geologist for data interpretation, are available. These programs are to be preferred rather than those developed by single scientists in the «first age» of computer research. However, these latter programs continue to be useful when powerful data elaboration systems are not easy available. A revised edition of the program for memorizing and processing data employed in Rome University by the Department of the Earth Sciences is presented here. This program is used in order to recover data contained in the data bank of the Tiber Delta. The running of a part of this System has still been explained in a previous work (Bellotti et al., 1986). But in these work a large part of the program was not presented as the peripheral programs needed further tests and refinings. The system allows to memorize the data of different kind, numerical, literal and graphical (names of fossils, minerals, coordinates, elevation, lithological sections, contour lines, mor-phological characters of the area, hydrography and so on). Several memorized data processing, the drawing of maps containing quoted planes of statistical indexes, lithological columns or schematic topographical maps on several scales, are possible as well as the calculus of the distance between remarkable points.
Lo studio condotto sulla parte emersa dell'apparato deltizio del Fiume Ombrone ha permesso di... more Lo studio condotto sulla parte emersa dell'apparato deltizio del Fiume Ombrone ha permesso di ricostruire le caratteristiche morfoevolutive degli stagni costieri, che contraddistinguono l'ala destra del delta, e l'accertamento della variazione della linea di riva dell'intero paraggio deltizio negli ultimi 70 anni. Sono state esaminate, inoltre, sia le caratteristiche dei sedimenti superficiali (tessitura e composizione principale), come anche l'architettura del sottosuolo.
The Latium and western Abruzzi “turbiditic complex” consists of four main basins oriented from N-... more The Latium and western Abruzzi “turbiditic complex” consists of four main basins oriented from N-S to NW-SE (Apennine trend). The four basins were conventlonally named as follows: a) Salto-Turano Trough to the north; b) Aniene-Sacco Trough to the west; c) Liri Trough in the middle; d) Tagllacozzo Trough, east of c). The terrigenous deposition of hemipelagic sediments ("Marne ad Orbulina” Formation) started in the upper Serravallian, extending upward along with turbiditic sediments, up to the end of the Tortonian. The turbiditic sediments show a widely articulated "deep sea fan" constitution with both a distributary area and depositional apparatus differently developed in each basin. The Salto-Turano basin is connected southward with the other three troughs, whereas these are separated by carbonatic shelf ridges. Within the Salto-Turano Basin, arenaceous facies are widespread with an erosive basal contact and "thinning and fining upward sequences". Minor pelitic-arenaceous facies are sometimes present. The Aniene-Sacco Basin in the northern area is mainly characterized by sand bodies while its central and southern area consists mostly of “outer-fan lobes" passing to fringe pelitic-arenaceous facies toward S and W. The vertical sequence of the Aniene-Sacco turbidite shows a "progradational" (coarsening-up) turbidite suite. Interlobe and fringe facies prevail into the Liri Trough and represent the first term of the turbiditic sequence. Outer-fan lobes over top and are partly interbedded with the previous sediments. Channelized sand bodies are unnoticeable. Proximal lobes and subordinate channelized sediments at top of the sequence fill the Tagliacozzo Basin. In the southern part of the trough distal lobes and fringe facies most probably underlie to the Neozoic alluvial sediments. The paleocurrent patterns show that clastic material flowed into the basin N to S and NW to SE. However a provenance from a western geographycal area could be hypotized on the basis of some petrographic data (from a fragment of the alpine chain to be localized, during Cainozoic, in the Tyrrhenian Sea and/or from the Sicilide and Liguride folds). The “turbidite complex” of Latium and western Abruzzi consists of sandy deep sea fan growing during the Tortonian into elongate troughs in the carbonatic Mesozoic basement, thus leading the turbiditic body to assume the geometry of a “chocked fan" in which physiographic elements appear to be distorted and developed in anomalous way; moreover the sediments are often partially covered by overthrusts of Mesozoic ridges.
At Passo delle Capannelle, along the National Road n. 80, linking up L’Aquila and Teramo, in the ... more At Passo delle Capannelle, along the National Road n. 80, linking up L’Aquila and Teramo, in the calcareous-marly formation type « scaglia » there outcropping, some sedimentary sheetings — that may be connected to those usually called Zoophycos — have been found. These sheetings consist in successions of shuffled and undisturbed sediment. These marks are present in the sediments all over the world from the Silurian period until today but are not yet completely considered for their importance; the large bibliography about this subject is fragmentary and dispersed, and offers to the student contrasting theories on their origin. In this work, the Author makes a rapid critical research of the present bibliography and a detailed description of the marks found at the Passo delle Capannelle; on the ground of the results of the study, made by the Stereoscan equipped with an energy dispersive X-ray analysis sistem (EDAS), too, the marks have been identified as the burrow of a roving polychaete mud-eating annelid. This annelid would have been living buried in the fine mud of the high sea to a depth between 50 and 150 m, excavating a fiat and webbed burrow.
This paper presents TrollHunter2020, a real-time detection mechanism we used to hunt for trolling... more This paper presents TrollHunter2020, a real-time detection mechanism we used to hunt for trolling narratives on Twitter during the 2020 U.S. elections. Trolling narratives form on Twitter as alternative explanations of polarizing events like the 2020 U.S. elections with the goal to conduct information operations or provoke emotional response. Detecting trolling narratives thus is an imperative step to preserve constructive discourse on Twitter and remove an influx of misinformation. Using existing techniques, this takes time and a wealth of data, which, in a rapidly changing election cycle with high stakes, might not be available. To overcome this limitation, we developed TrollHunter2020 to hunt for trolls in real-time with several dozens of trending Twitter topics and hashtags corresponding to the candidates' debates, the election night, and the election aftermath. TrollHunter2020 collects trending data and utilizes a correspondence analysis to detect meaningful relationships between the top nouns and verbs used in constructing trolling narratives while they emerge on Twitter. Our results suggest that the TrollHunter2020 indeed captures the emerging trolling narratives in a very early stage of an unfolding polarizing event. We discuss the utility of TrollHunter2020 for early detection of information operations or trolling and the implications of its use in supporting a constrictive discourse on the platform around polarizing topics.
Page 1. Late Quaternary landscape evolution of the Tiber River delta plain (Central Italy): new e... more Page 1. Late Quaternary landscape evolution of the Tiber River delta plain (Central Italy): new evidence from pollen data, biostratigraphy and 14C dating by ... Hier akkumulierte der Ti-ber ein Delta, das lange Zeit eine regressive Tendenz zeigte. ...
A new x-ray diffraction procedure for the determination of cristobalite in the presence of amorph... more A new x-ray diffraction procedure for the determination of cristobalite in the presence of amorphous silica is described. The standards are obtained by deposition of thin layers of watery suspensions of cristobalite and amorphous silica mixtures on silver or lead disks or cellulosa filters. Six calibration curves are then calculated to reduce weight and sampling errors. Six mcg of cristobalite mixed with 594 mcg of amorphus silica is the lowest detectable limit. The method may be used for the analysis of both raw materials and respirable dust.
Mineralogical and sedimentological features of conglomeratic bed, founded in the “minor basin” of... more Mineralogical and sedimentological features of conglomeratic bed, founded in the “minor basin” of Tagliacozzo, are described in this paper. The conglomeratic bed have been displaced in the emipelagic clay, by a debris flow flowing, into the basin, from NW to SE. This bed is a carbonatic elements of the Calcari a Briozoi e Litotamni Formation; extrabacinal clasts, probably deriving from a fragment of Thirrhenic Alpine Chaine (Alvarez, 1976), are characterized by fragments of metamorphic, volcanic and sedimentary rocks. The depositional environment of the conglomeratic bed and emipelagic clay is porbably the base of Continental slope.
Il sistema di calcolo degli indici statistici secondo FOLK & WARD (1957) viene da trenta ... more Il sistema di calcolo degli indici statistici secondo FOLK & WARD (1957) viene da trenta anni quasi universalmente utilizzato per il confronto delle distribuzioni granulometriche relative ai sedimenti incoerenti. Le semplificazioni insite nella risoluzione grafica di passaggi matematici di notevole complessità superano dì gran lunga gli effetti deleteri dell'imprecisione relativa alla trasposizione grafica dei dati. Per questo motivo ancora oggi, pur in presenza di mezzi di calcolo di notevole potenza che permetterebbero una rapidissima e ben più precisa elaborazione dei dati granulometrici attraverso il metodo dei momenti matematici, nella gran parte dei casi si continua ad utilizzare il metodo grafico, anche per la facilità di confronto dei dati così ottenuti con quelli archiviati negli anni precedenti con lo stesso metodo, Lo scrivente, dopo essersi occupato in precedenti lavori di fornire una scala di valutazione relativa agli indici statistici ottenuti con il metodo dei momenti matematici, con il presente articolo intende mettere a disposizione anche di chi utilizza il metodo grafico le facilitazioni proprie finora di chi, adottando il metodo dei momenti matematici poteva utilizzare moderni sistemi di calcolo con rapidità di elaborazione, ripetitività dei risultati e quasi totale assenza di errori accidentali.
Sono esposti i risultati della trattazione matematica della dinamica delle particelle in sediment... more Sono esposti i risultati della trattazione matematica della dinamica delle particelle in sedimentazione durante prelievi in aria. Viene evidenziata l’influenza della durata del prelievo e delle caratteristiche granulometriche degli inquinanti sulla zona volumica che li contiene, con particolare riferimento alla massima altezza di prelevamento. Si presuppone che il mezzo in cui le particelle sedimentano sia in quiete. Summary . The results of the mathematical treatment about the dynamics of the sedimenting particles during the drawings occurring in the air are reported. It is also stressed the influence of the drawing length and of the grain-size characteristics of the polluting agents on them, referring in particular to the drawing maximum height. It is supposed that the medium in which the particles fall is at rest.
In the last years, the great development of the computer programs is going to reach the geologica... more In the last years, the great development of the computer programs is going to reach the geological stratigraphical field. As a matter of fact, very powerful programs, which leave more to the geologist for data interpretation, are available. These programs are to be preferred rather than those developed by single scientists in the «first age» of computer research. However, these latter programs continue to be useful when powerful data elaboration systems are not easy available. A revised edition of the program for memorizing and processing data employed in Rome University by the Department of the Earth Sciences is presented here. This program is used in order to recover data contained in the data bank of the Tiber Delta. The running of a part of this System has still been explained in a previous work (Bellotti et al., 1986). But in these work a large part of the program was not presented as the peripheral programs needed further tests and refinings. The system allows to memorize the data of different kind, numerical, literal and graphical (names of fossils, minerals, coordinates, elevation, lithological sections, contour lines, mor-phological characters of the area, hydrography and so on). Several memorized data processing, the drawing of maps containing quoted planes of statistical indexes, lithological columns or schematic topographical maps on several scales, are possible as well as the calculus of the distance between remarkable points.
Lo studio condotto sulla parte emersa dell'apparato deltizio del Fiume Ombrone ha permesso di... more Lo studio condotto sulla parte emersa dell'apparato deltizio del Fiume Ombrone ha permesso di ricostruire le caratteristiche morfoevolutive degli stagni costieri, che contraddistinguono l'ala destra del delta, e l'accertamento della variazione della linea di riva dell'intero paraggio deltizio negli ultimi 70 anni. Sono state esaminate, inoltre, sia le caratteristiche dei sedimenti superficiali (tessitura e composizione principale), come anche l'architettura del sottosuolo.
The Latium and western Abruzzi “turbiditic complex” consists of four main basins oriented from N-... more The Latium and western Abruzzi “turbiditic complex” consists of four main basins oriented from N-S to NW-SE (Apennine trend). The four basins were conventlonally named as follows: a) Salto-Turano Trough to the north; b) Aniene-Sacco Trough to the west; c) Liri Trough in the middle; d) Tagllacozzo Trough, east of c). The terrigenous deposition of hemipelagic sediments ("Marne ad Orbulina” Formation) started in the upper Serravallian, extending upward along with turbiditic sediments, up to the end of the Tortonian. The turbiditic sediments show a widely articulated "deep sea fan" constitution with both a distributary area and depositional apparatus differently developed in each basin. The Salto-Turano basin is connected southward with the other three troughs, whereas these are separated by carbonatic shelf ridges. Within the Salto-Turano Basin, arenaceous facies are widespread with an erosive basal contact and "thinning and fining upward sequences". Minor pelitic-arenaceous facies are sometimes present. The Aniene-Sacco Basin in the northern area is mainly characterized by sand bodies while its central and southern area consists mostly of “outer-fan lobes" passing to fringe pelitic-arenaceous facies toward S and W. The vertical sequence of the Aniene-Sacco turbidite shows a "progradational" (coarsening-up) turbidite suite. Interlobe and fringe facies prevail into the Liri Trough and represent the first term of the turbiditic sequence. Outer-fan lobes over top and are partly interbedded with the previous sediments. Channelized sand bodies are unnoticeable. Proximal lobes and subordinate channelized sediments at top of the sequence fill the Tagliacozzo Basin. In the southern part of the trough distal lobes and fringe facies most probably underlie to the Neozoic alluvial sediments. The paleocurrent patterns show that clastic material flowed into the basin N to S and NW to SE. However a provenance from a western geographycal area could be hypotized on the basis of some petrographic data (from a fragment of the alpine chain to be localized, during Cainozoic, in the Tyrrhenian Sea and/or from the Sicilide and Liguride folds). The “turbidite complex” of Latium and western Abruzzi consists of sandy deep sea fan growing during the Tortonian into elongate troughs in the carbonatic Mesozoic basement, thus leading the turbiditic body to assume the geometry of a “chocked fan" in which physiographic elements appear to be distorted and developed in anomalous way; moreover the sediments are often partially covered by overthrusts of Mesozoic ridges.
At Passo delle Capannelle, along the National Road n. 80, linking up L’Aquila and Teramo, in the ... more At Passo delle Capannelle, along the National Road n. 80, linking up L’Aquila and Teramo, in the calcareous-marly formation type « scaglia » there outcropping, some sedimentary sheetings — that may be connected to those usually called Zoophycos — have been found. These sheetings consist in successions of shuffled and undisturbed sediment. These marks are present in the sediments all over the world from the Silurian period until today but are not yet completely considered for their importance; the large bibliography about this subject is fragmentary and dispersed, and offers to the student contrasting theories on their origin. In this work, the Author makes a rapid critical research of the present bibliography and a detailed description of the marks found at the Passo delle Capannelle; on the ground of the results of the study, made by the Stereoscan equipped with an energy dispersive X-ray analysis sistem (EDAS), too, the marks have been identified as the burrow of a roving polychaete mud-eating annelid. This annelid would have been living buried in the fine mud of the high sea to a depth between 50 and 150 m, excavating a fiat and webbed burrow.
This paper presents TrollHunter2020, a real-time detection mechanism we used to hunt for trolling... more This paper presents TrollHunter2020, a real-time detection mechanism we used to hunt for trolling narratives on Twitter during the 2020 U.S. elections. Trolling narratives form on Twitter as alternative explanations of polarizing events like the 2020 U.S. elections with the goal to conduct information operations or provoke emotional response. Detecting trolling narratives thus is an imperative step to preserve constructive discourse on Twitter and remove an influx of misinformation. Using existing techniques, this takes time and a wealth of data, which, in a rapidly changing election cycle with high stakes, might not be available. To overcome this limitation, we developed TrollHunter2020 to hunt for trolls in real-time with several dozens of trending Twitter topics and hashtags corresponding to the candidates' debates, the election night, and the election aftermath. TrollHunter2020 collects trending data and utilizes a correspondence analysis to detect meaningful relationships between the top nouns and verbs used in constructing trolling narratives while they emerge on Twitter. Our results suggest that the TrollHunter2020 indeed captures the emerging trolling narratives in a very early stage of an unfolding polarizing event. We discuss the utility of TrollHunter2020 for early detection of information operations or trolling and the implications of its use in supporting a constrictive discourse on the platform around polarizing topics.
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