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Geochemical and isotopic compositions of minerals and bulk rocks of the Chachimbiro Volcanic Complex (Northern Andes, Ecuador)

This dataset provides geochemical data from from the Quaternary Chachimbiro Volcanic Complex (CVC), situated in the Western Cordillera of Ecuador, Northern Andes (0.468°N, 78.287°W). The CVC is subdivided into 4 eruptive stages (CH1, CH2, CH3, CH4) ranging in age between ~400 and ~4 ka ago (Bellver-Baca et al., 2020). The CH1 stage consists of andesitic flows erupted between 405.7 ± 20.0 and 298.6 ± 32.9 ka with collapse of the pre-existing cone at the end of the effusive period (File #1). The following CH2 stage (121.75 ± 23.2 -36.08 ± 2.8 ka) consists of andesitic to dacitic domes and pyroclastic rocks which also suffered a collapse event as shown by the scar and the uprooted domes in the hillside of the edifice (File #1). The CH3 unit (36.08 ± 0.28 – 22.73 ± 0.12 ka) consists of two main andesitic to dacitic domes (Hugá and Albují: H and A, respectively, in File #1) and effusive rocks. CH4 consists of a volumetrically small rhyodacitic pyroclastic unit which was produced by a lateral blast dated at 5.5-5.8 ky ago. A younger pyroclastic episode (<4.15 ka ago) has been related to the Pucará dome (Comida, 2012), but rocks of this event have not been investigated in the present study. The bulk rock and mineral data are used to reconstruct the plumbing system beneath the CVC during its ~400 ka long lifetime. Since the temporal geochemical evolution of CVC bulk rocks towards higher values of adakite-like indices (e.g., Sr/Y, La/Yb) bears strong similarities to that of magmatic systems associated with supergiant porphyry copper deposits, these data may serve to better understand how adakite-like signatures are acquired in fertile arc magmatic systems with metallogenic implications. Files included are: • 2024-018_Chiaradia-et-al_Table-1_Sample-overview: sample overview table with coordinates of and type of analyses carried out on each sample (Table #1) • 2024-018_Chiaradia-et-al_File_1_map: a geological map with location of investigated samples (File #1) • 2024-018_Chiaradia-et-al_File_2_WholeRocks: geochemical and radiogenic isotope data on bulk rocks (File #2). • 2024-018_Chiaradia-et-al_File_3_Pyroxene: contains microprobe and LA-ICP-MS major and trace element analyses of clino- and orthopyroxenes from the CVC and P-T conditions retrieved from clinopyroxene compositions (File #3) • 2024-018_Chiaradia-et-al_File_4_Amphibole: contains microprobe and LA-ICP-MS major and trace element analyses of amphiboles from the CVC and P-T-H2Omelt, fO2 conditions retrieved from amphibole compositions (File #4). • 2024-018_Chiaradia-et-al_File_5_Plagioclase: contains microprobe and LA-ICP-MS major and trace element analyses of plagioclases from the CVC (File #5). • 2024-018_Chiaradia-et-al_File_6_Equilibrium tests: reports the calculations to retrieve pressure and temperature data from clinopyroxene-melt equilibrium and clinopyroxene-only composition (File #6). • 2024-018_Chiaradia-et-al_File_7_CPX_Thermo_Barometry: reports the calculations to obtain P-T conditions from clinopyroxene-orthopyroxene equilibria in the same thin section (File #7). • 2024-018_Chiaradia-et-al_File_8_Cpx_Opx_Thermo_Barometry: reports the equilibrium tests between minerals (clinopyroxene, orthopyroxene, amphibole) and host rock compositions and the P-T values retrieved by clinopyroxene and amphibole analyses that passed the test (File #8). Associated RStudio Scripts are available as https://doi.org/10.5880/fidgeo.2025.010 (Chiarada, 2025).

Radiogenic isotope compositions of eruption products from the 2019 paroxysmal eruptions at Stromboli Volcano

The periodic volcanic activity of Stromboli Volcano, Aeolian Islands, Italy, is interrupted by paroxysmal eruptions on a decadal interval. In 2019, two strong paroxysms on July 3rd and August 28th, ended a more than a decade long period of regular strombolian activity. During normal strombolian activity the volcano erupts highly porphyritic scoria and lava (HP) with a shoshonitic basalt composition. In paroxysmal eruptions the HP material is mingled with low porphyritic (LP) pumices. This dataset includes the first radiogenic isotope data on the bulk compositions of the LP and HP components erupted on July 3rd 2019, and a HP sample from the lava flow that followed the paroxysm, and a LP sample from the paroxysm on August 28th 2019. The analyzed radiogenic isotope ratios include Sr, Nd, Hf, and Pb. This dataset further includes in-situ EPMA and LA-ICP_MS measurements of major and trace elements in the glass, olivine, plagioclase and clinopyroxene phases.

Radiometric Dates from the South American Andes and Adjacent Areas: A Compilation - part 2 sedimentary rocks

A compilation of 90,688 published radiometric dates for sedimentary rocks from the South American Andes and adjacent parts of South America have been tabulated for access by researchers via GEOROC Expert Datasets. The compilation exists as a spreadsheet for access via MS Excel, Google Sheets, and other spreadsheet applications. Initial igneous compilations were utilized in two publications by the author, Pilger (1981, 1984). The compilations have been added to in subsequent years with the metamorphic and sedimentary compilations separated in the last few years. Locations in latitude and longitude are largely taken from the original source, if provided, with UTM locations maintained and converted; in some cases, sample locations were digitized from electronic maps if coordinates were otherwise not available. Analytical results are not included to prevent the files from becoming too large. The existing compilation incorporates compilations by other workers in smaller regions of the Andes. References to original and compilation sources are included. While I am updating reconstructions of the South American and Nazca/Farallon plates, incorporating recent studies in the three oceans, for comparison with the igneous dates for the past 80 m. y., it is hoped that the spreadsheets will be of value to other workers. Reliability: In most cases the data have been copy/pasted from published or appendix tables. In a few cases, the location has been digitized from published maps; the (equatorial equidistant) maps were copied into Google Earth and positioned according to indicated coordinates, with locations digitized and copied/pasted into the spreadsheet. (It is possible that published maps are conventional Mercator-based, even if not so identified, rather than either equatorial equidistant or Universal Transverse Mercator; this can be a source of error in location. For UTMs, the errors should be minor.) Duplicates are largely recognized by equivalent IDs, dates, and uncertainties. Where primary sources have been accessed, duplicate data points in compilations are deleted. (Analytic data are NOT included.) This compilation is part of a series. Companion compilations of radiometric dates from igneous and metamorphic rocks are available at https://doi.org/10.5880/digis.e.2023.005 and https://doi.org/10.5880/digis.e.2023.007, respectively.

Radiometric Dates from the South American Andes and Adjacent Areas: A Compilation - part 3 metamorphic rocks

A compilation of 29,574 published radiometric dates for metamorphic rocks from the South American Andes and adjacent parts of South America have been tabulated for access by researchers via GEOROC Expert Datasets. The compilation exists as a spreadsheet for access via MS Excel, Google Sheets, and other spreadsheet applications. Initial igneous compilations were utilized in two publications by the author, Pilger (1981, 1984). The compilations have been added to in subsequent years with the metamorphic and sedimentary compilations separated in the last few years. Locations in latitude and longitude are largely taken from the original source, if provided, with UTM locations maintained and converted; in some cases, sample locations were digitized from electronic maps if coordinates were otherwise not available. Analytical results are not included to prevent the files from becoming too large. The existing compilation incorporates compilations by other workers in smaller regions of the Andes. References to original and compilation sources are included. While I am updating reconstructions of the South American and Nazca/Farallon plates, incorporating recent studies in the three oceans, for comparison with the igneous dates for the past 80 m. y., it is hoped that the spreadsheets will be of value to other workers. Reliability: In most cases the data have been copy/pasted from published or appendix tables. In a few cases, the location has been digitized from published maps; the (equatorial equidistant) maps were copied into Google Earth and positioned according to indicated coordinates, with locations digitized and copied/pasted into the spreadsheet. (It is possible that published maps are conventional Mercator-based, even if not so identified, rather than either equatorial equidistant or Universal Transverse Mercator; this can be a source of error in location. For UTMs, the errors should be minor.) Duplicates are largely recognized by equivalent IDs, dates, and uncertainties. Where primary sources have been accessed, duplicate data points in compilations are deleted. (Analytic data are NOT included.) This compilation is part of a series. Companion compilations of radiometric dates from igneous and sedimentary rocks are available at https://doi.org/10.5880/digis.e.2023.005 and https://doi.org/10.5880/digis.e.2023.006, respectively.

Radiometric Dates from the South American Andes and Adjacent Areas: A Compilation - part 1 igenous rocks

A compilation of 39,070 published radiometric dates for igneous rocks from the South American Andes and adjacent parts of South America have been tabulated for access by researchers via GEOROC Expert Datasets. The compilation exists as a spreadsheet for access via MS Excel, Google Sheets, and other spreadsheet applications. Initial igneous compilations were utilized in two publications by the author, Pilger (1981, 1984). The compilations have been added to in subsequent years with the metamorphic and sedimentary compilations separated in the last few years. Locations in latitude and longitude are largely taken from the original source, if provided, with UTM locations maintained and converted; in some cases, sample locations were digitized from electronic maps if coordinates were otherwise not available. Analytical results are not included to prevent the files from becoming too large. The existing compilation incorporates compilations by other workers in smaller regions of the Andes. References to original and compilation sources are included. While I am updating reconstructions of the South American and Nazca/Farallon plates, incorporating recent studies in the three oceans, for comparison with the igneous dates for the past 80 m. y., it is hoped that the spreadsheets will be of value to other workers. Reliability: In most cases the data have been copy/pasted from published or appendix tables. In a few cases, the location has been digitized from published maps; the (equatorial equidistant) maps were copied into Google Earth and positioned according to indicated coordinates, with locations digitized and copied/pasted into the spreadsheet. (It is possible that published maps are conventional Mercator-based, even if not so identified, rather than either equatorial equidistant or Universal Transverse Mercator; this can be a source of error in location. For UTMs, the errors should be minor.) Duplicates are largely recognized by equivalent IDs, dates, and uncertainties. Where primary sources have been accessed, duplicate data points in compilations are deleted. (Analytic data are NOT included.) This compilation is part of a series. Companion compilations of radiometric dates from sedimentary and metamorphic rocks are available at https://doi.org/10.5880/digis.e.2023.006 and https://doi.org/10.5880/digis.e.2023.007, respectively.

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