The Volcanic-Rich Layer of the “Camporotondo (Marche, Italy)” Section: Petrography and Sedimentation of an Unknown Distal Messinian Eruption
A Messinian and lithified horizon enriched in volcanic particles with thicknesses of 170–180 cm crops in the Camporotondo (CR) section (Marche, Italy). This volcanic-rich layer (VRL) was investigated by field plus mesoscopic observations, X-ray powder diffraction (XRPD), scanning electron microscopy...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-07-01
|
| Series: | Minerals |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2075-163X/12/7/893 |
| _version_ | 1797416825157320704 |
|---|---|
| author | Davide Potere Vittorio Scisciani Monica Piochi Pietro Paolo Pierantoni Angela Mormone Manuela Nazzari Piergiorgio Scarlato Gianluca Iezzi |
| author_facet | Davide Potere Vittorio Scisciani Monica Piochi Pietro Paolo Pierantoni Angela Mormone Manuela Nazzari Piergiorgio Scarlato Gianluca Iezzi |
| author_sort | Davide Potere |
| collection | DOAJ |
| description | A Messinian and lithified horizon enriched in volcanic particles with thicknesses of 170–180 cm crops in the Camporotondo (CR) section (Marche, Italy). This volcanic-rich layer (VRL) was investigated by field plus mesoscopic observations, X-ray powder diffraction (XRPD), scanning electron microscopy (SEM), bulk composition methods and electron-microprobe analysis (EMPA). The quantitative textural features of volcanic and sedimentary components were determined by 2D image analysis. The lowermost massive 70–80 cm portion is free of sedimentary structure or characterised only by plane-parallel ones, whereas the uppermost one is undulated and cross-laminated. The XRPD and SEM outcomes unveil that the VRL of CR is mainly composed of glassy shards (≥80 area%), a variable amount of sedimentary minerals (<20 area%) and a very low content of magmatic minerals (few area%). The bulk and micro-chemical attributes of volcanic and glassy materials are rhyolitic and almost identical to previous VRLs dated at 5.5 Ma (VRL-5.5). The signatures of immobile elements and the high amount of H<sub>2</sub>O present in the glass fraction suggest a provenance from a convergent geodynamic setting. The 2D image analysis on SEM observations show that the VRL-5.5 of CR is composed of very fine and sorted (averages of <i>M</i><sub>Z</sub> of 5,72 and <i>σ</i><sub><i>i</i></sub> of 0,70), scarcely vesicular, glass shards, with similar long and short size dimensions, shape and roundness. The VRL-5.5 of CR is free of large minerals and fossils. The coupling of mesoscopic and microscopic determinations indicates that the lowermost interval was deposited such as a primary tephra, i.e., fallout pyroclasts sinking in seawater. Instead, the uppermost interval derives from local, low-energy and sin-depositional remobilisation of the same VRL-5.5. The textural attributes of the volcanic fractions, the sedimentological features and the thickness of the VRL at CR correspond to the westward deposit of a still unknown eruption likely occurred at 5.5 Ma. |
| first_indexed | 2024-03-09T06:09:46Z |
| format | Article |
| id | doaj.art-cedeea4439a34c789ecbe61619ec8090 |
| institution | Directory Open Access Journal |
| issn | 2075-163X |
| language | English |
| last_indexed | 2024-03-09T06:09:46Z |
| publishDate | 2022-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Minerals |
| spelling | doaj.art-cedeea4439a34c789ecbe61619ec80902023-12-03T12:00:20ZengMDPI AGMinerals2075-163X2022-07-0112789310.3390/min12070893The Volcanic-Rich Layer of the “Camporotondo (Marche, Italy)” Section: Petrography and Sedimentation of an Unknown Distal Messinian EruptionDavide Potere0Vittorio Scisciani1Monica Piochi2Pietro Paolo Pierantoni3Angela Mormone4Manuela Nazzari5Piergiorgio Scarlato6Gianluca Iezzi7Dipartimento di Ingegneria & Geologia, Università G. d’Annunzio, Via dei Vestini 30, 66100 Chieti, ItalyDipartimento di Ingegneria & Geologia, Università G. d’Annunzio, Via dei Vestini 30, 66100 Chieti, ItalyOsservatorio Vesuviano, Istituto Nazionale di Geofisica e Vulcanologia, 80124 Naples, ItalyScuola di Scienze e Tecnologia, Università degli Studi di Camerino, 62032 Camerino, ItalyOsservatorio Vesuviano, Istituto Nazionale di Geofisica e Vulcanologia, 80124 Naples, ItalyIstituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Roma, ItalyIstituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Roma, ItalyDipartimento di Ingegneria & Geologia, Università G. d’Annunzio, Via dei Vestini 30, 66100 Chieti, ItalyA Messinian and lithified horizon enriched in volcanic particles with thicknesses of 170–180 cm crops in the Camporotondo (CR) section (Marche, Italy). This volcanic-rich layer (VRL) was investigated by field plus mesoscopic observations, X-ray powder diffraction (XRPD), scanning electron microscopy (SEM), bulk composition methods and electron-microprobe analysis (EMPA). The quantitative textural features of volcanic and sedimentary components were determined by 2D image analysis. The lowermost massive 70–80 cm portion is free of sedimentary structure or characterised only by plane-parallel ones, whereas the uppermost one is undulated and cross-laminated. The XRPD and SEM outcomes unveil that the VRL of CR is mainly composed of glassy shards (≥80 area%), a variable amount of sedimentary minerals (<20 area%) and a very low content of magmatic minerals (few area%). The bulk and micro-chemical attributes of volcanic and glassy materials are rhyolitic and almost identical to previous VRLs dated at 5.5 Ma (VRL-5.5). The signatures of immobile elements and the high amount of H<sub>2</sub>O present in the glass fraction suggest a provenance from a convergent geodynamic setting. The 2D image analysis on SEM observations show that the VRL-5.5 of CR is composed of very fine and sorted (averages of <i>M</i><sub>Z</sub> of 5,72 and <i>σ</i><sub><i>i</i></sub> of 0,70), scarcely vesicular, glass shards, with similar long and short size dimensions, shape and roundness. The VRL-5.5 of CR is free of large minerals and fossils. The coupling of mesoscopic and microscopic determinations indicates that the lowermost interval was deposited such as a primary tephra, i.e., fallout pyroclasts sinking in seawater. Instead, the uppermost interval derives from local, low-energy and sin-depositional remobilisation of the same VRL-5.5. The textural attributes of the volcanic fractions, the sedimentological features and the thickness of the VRL at CR correspond to the westward deposit of a still unknown eruption likely occurred at 5.5 Ma.https://www.mdpi.com/2075-163X/12/7/893volcanic glassXRPDimage analysispetrographysedimentationeruption |
| spellingShingle | Davide Potere Vittorio Scisciani Monica Piochi Pietro Paolo Pierantoni Angela Mormone Manuela Nazzari Piergiorgio Scarlato Gianluca Iezzi The Volcanic-Rich Layer of the “Camporotondo (Marche, Italy)” Section: Petrography and Sedimentation of an Unknown Distal Messinian Eruption Minerals volcanic glass XRPD image analysis petrography sedimentation eruption |
| title | The Volcanic-Rich Layer of the “Camporotondo (Marche, Italy)” Section: Petrography and Sedimentation of an Unknown Distal Messinian Eruption |
| title_full | The Volcanic-Rich Layer of the “Camporotondo (Marche, Italy)” Section: Petrography and Sedimentation of an Unknown Distal Messinian Eruption |
| title_fullStr | The Volcanic-Rich Layer of the “Camporotondo (Marche, Italy)” Section: Petrography and Sedimentation of an Unknown Distal Messinian Eruption |
| title_full_unstemmed | The Volcanic-Rich Layer of the “Camporotondo (Marche, Italy)” Section: Petrography and Sedimentation of an Unknown Distal Messinian Eruption |
| title_short | The Volcanic-Rich Layer of the “Camporotondo (Marche, Italy)” Section: Petrography and Sedimentation of an Unknown Distal Messinian Eruption |
| title_sort | volcanic rich layer of the camporotondo marche italy section petrography and sedimentation of an unknown distal messinian eruption |
| topic | volcanic glass XRPD image analysis petrography sedimentation eruption |
| url | https://www.mdpi.com/2075-163X/12/7/893 |
| work_keys_str_mv | AT davidepotere thevolcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT vittorioscisciani thevolcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT monicapiochi thevolcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT pietropaolopierantoni thevolcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT angelamormone thevolcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT manuelanazzari thevolcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT piergiorgioscarlato thevolcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT gianlucaiezzi thevolcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT davidepotere volcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT vittorioscisciani volcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT monicapiochi volcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT pietropaolopierantoni volcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT angelamormone volcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT manuelanazzari volcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT piergiorgioscarlato volcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption AT gianlucaiezzi volcanicrichlayerofthecamporotondomarcheitalysectionpetrographyandsedimentationofanunknowndistalmessinianeruption |