/* DATA DESCRIPTION:
Citation:	Belo, Julie (2025): Major element glass data of marine tephras around São Miguel Island, Azores [dataset publication series]. PANGAEA, https://doi.org/10.1594/PANGAEA.986779
Abstract:	A total of 44 gravity cores were collected in the Azores region in 2017, during the R/V Meteor cruise M141/1. Based on their length, content in tephra layers, and spatial distribution around São Miguel, 22 cores have been carefully selected as the most representative to gain insights on the volcanic history and the depositional marine environment around the islands of the eastern group of the archipelago. In total, 454 samples from 350 ash- or pumice/scoria/lapilli- bearing horizons were examined. Here we present the major element glass data of the Pleistocene to Holocene marine tephra record around the eastern islands of the Azores. Marine lapilli samples were cleaned in an ultrasonic bath and then crushed. All ash samples and the previously crushed lapilli samples were wet-sieved into different grain size fractions. The 125-63 microns fraction was embedded with epoxy in pre-drilled acrylic mounts and polished for geochemical micro-analyses. Major and minor element compositions of glass shards were conducted using a JEOL JXA 8200 wavelength dispersive EMP at GEOMAR Helmholtz-Centre for Ocean Research, Kiel, Germany.
	Every 60 individual glass shards analyses were bracketed by a set of four standard analyses. We analyzed 15–25 single glass shards per sample (~7,000 analyses in total). Outliers with totals below 92 wt.%, as well as accidental mineral analyses were removed from the dataset.
Project(s):	Volcanism - climate interaction: A test case from the Azores archipelago (VolClimA)
Funding:	German Research Foundation (DFG) (URI: http://www.dfg.de/en/), grant/award no. 509166013: VolClimA
Coverage:	MEDIAN LATITUDE: 37.312576 * MEDIAN LONGITUDE: -25.415492 * SOUTH-BOUND LATITUDE: 35.899667 * WEST-BOUND LONGITUDE: -27.493667 * NORTH-BOUND LATITUDE: 38.267667 * EAST-BOUND LONGITUDE: -22.460333
	DATE/TIME START: 2017-09-11T10:31:00 * DATE/TIME END: 2017-09-30T15:14:00
License:	Creative Commons Attribution 4.0 International (CC-BY-4.0) (URI: https://creativecommons.org/licenses/by/4.0/)
Size:	22 datasets
*/
/* TABULAR SUMMARY OF DATASETS LISTED IN THIS COLLECTION: */
Filename	Citation of child dataset
M141-1_1136.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1136-1. https://doi.org/10.1594/PANGAEA.986781
M141-1_1138.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1138-1. https://doi.org/10.1594/PANGAEA.987018
M141-1_1140.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1140-1. https://doi.org/10.1594/PANGAEA.987019
M141-1_1144.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1144-1. https://doi.org/10.1594/PANGAEA.987021
M141-1_1146.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1146-3. https://doi.org/10.1594/PANGAEA.987022
M141-1_1148.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1148-1. https://doi.org/10.1594/PANGAEA.987023
M141-1_1150.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1150-1. https://doi.org/10.1594/PANGAEA.987024
M141-1_1152.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1152-1. https://doi.org/10.1594/PANGAEA.987025
M141-1_1154.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1154-1. https://doi.org/10.1594/PANGAEA.987026
M141-1_1156.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1156-1. https://doi.org/10.1594/PANGAEA.987027
M141-1_1160.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1160-1. https://doi.org/10.1594/PANGAEA.987028
M141-1_1162.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1162-3. https://doi.org/10.1594/PANGAEA.987029
M141-1_1164.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1164-1. https://doi.org/10.1594/PANGAEA.987030
M141-1_1168.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1168-1. https://doi.org/10.1594/PANGAEA.987031
M141-1_1176.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1176-1. https://doi.org/10.1594/PANGAEA.987033
M141-1_1184.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1184-1. https://doi.org/10.1594/PANGAEA.987035
M141-1_1236.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1236-1. https://doi.org/10.1594/PANGAEA.987036
M141-1_1238.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1238-1. https://doi.org/10.1594/PANGAEA.987038
M141-1_1240.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1240-1. https://doi.org/10.1594/PANGAEA.987039
M141-1_1245.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1245-1. https://doi.org/10.1594/PANGAEA.987040
M141-1_1247.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1247-1. https://doi.org/10.1594/PANGAEA.987041
M141-1_1249.tab	Belo, Julie (2025): Major element glass data of marine tephras from sediment core M141/1_1249-1. https://doi.org/10.1594/PANGAEA.987042
