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Compilation of global Archean and Paleoproterozoic sanukitoid geochemical data

Sanukitoids, also referred to as high-Mg diorites, are a distinctive type of igneous rock from the late Archean-early Proterozoic, and are characterised by enrichment in both compatible elements (e.g. Mg, Ni, Cr) and incompatible elements (e.g. Ba, Sr, light rare earth elements). Their geochemistry is typically interpreted as recording petrogenesis of their parental magmas via interaction between mantle peridotite and recycled crust-derived component (e.g. metabasite melts, sediment melts, aqueous fluids), and is often considered to be "transitional" between that of Archean sodic tonalite-trondhjemite-granodiorite (TTG) suites and post-Archean potassic granites. This dataset presents a global compilation of all Archean-Paleoproterozoic rocks that have been described as "sanukitoid" in published literature, and consists of over 3600 individual samples. Whole rock major and trace element concentrations, radiogenic isotope compositions and stable isotope compositions are compiled in the dataset alongside reported magmatic ages of the samples. The dataset is provided both as an Excel workbook divided by craton (file: 2025-003_Spencer-et-al_Sanukitoid-Compilation.xlsx) and as a single CSV file (file: 2025-003_Spencer-et-al_Sanukitoid-Compilation.csv). Sanukitoid magmatism has been described on almost every Archean craton globally. Most reported sanukitoid magmatism occurred during the late Mesoarchean-Neoarchean (2.95 - 2.5 Ga), with another peak in sanukitoid magmatism in the mid-Paleoproterozoic (2.2 - 2.0 Ga). Older sanukitoid occurrences dating back to the Paleoarchean (>3.2 Ga) are also described in the literature.

Compilation of global Archean high-Sr tonalite-trondhjemite-granodiorite (TTG) geochemical data

Tonalite-trondhjemite-granodiorite (TTG) suites are the main constituent of Archean (4-2.5 Ga) continental crust. High-Sr TTGs are a subgroup of "high-pressure" TTGs characterised by very high Sr concentrations (>500 ppm, but often >700 ppm) and Sr/Y (>100), in addition to K2O/N2O<0.5, Yb<0.4 ppm and La/Yb>60 at SiO2≈70 wt%. High-Sr TTGs may have formed via fractional crystallisation of metasomatised mantle-derived sanukitoid magmas, in contrast to the dominant petrogenetic model for "high-pressure" TTGs involving metabasite partial melting at pressures >2 GPa. This dataset presents a compilation of global high-Sr TTG occurrences identified from published literature, and contains their compiled major and trace element and Nd isotope compositions.

Titanium stable isotope compositions of Neoarchean tonalite-trondhjemite-granodiorite (TTG) suites from the Eastern Goldfields Superterrane, Yilgarn Craton

We report the titanium (Ti) stable isotope compositions (δ49Ti) of Neoarchean (ca. 2700-2650 Ma) tonalite-trondhjemite-granodiorite (TTG) suites from the Eastern Goldfields Superterrane, Yilgarn Craton. Samples were selected to cover the full range of trace element compositions exhibited by TTGs, and are primarily from the Kalgoorlie-Kambalda region of the Kalgoorlie Terrane. Ti stable isotope compositions were measured using multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) at the Cardiff Earth Laboratory for Trace Element and Isotope Chemistry (CELTIC), Cardiff University. The Ti isotope compositions of these samples (file: 2025-009_Spencer-et-al_Ti-Isotope-Data.xlsx) are presented alongside a compilation of their major and trace element concentrations (file: 2025-009_Spencer-et-al_Compiled-Isotope-Major-Trace-Element-Data.xlsx) taken from the Western Australian Geochemistry Database (WACHEM). Most TTG samples have δ49Ti values between 0.2 to 0.6‰ that increase with SiO2 content, while two highly evolved TTGs have δ49Ti > 1‰. At SiO2 ≈ 70 wt% the different TTG geochemical groups display distinct Ti isotope compositions.

Combined noble gas analyses and p-T estimates from mineral separates and xenoliths, as well as noble gas analyses from free gas: A study of the origin of young(est) volcanism and magmatic activity in western Bohemia, Czech Republic

The western Eger Rift in the Czech Republic is a currently inactive volcanic area characterized by earthquake swarms and degassing of mantle-derived fluids. Gases obtained from minerals and from repeatedly sampled free gases are used to trace the origin and evolution of volatiles and determine the conditions of the magma reservoir. Helium isotopes in fluids and minerals are up to 5.95 RA, with 20Ne/22Ne ratios up to ~11.0 and 21Ne/22Ne ratios up to ~0.048, suggesting a mixed atmospheric-mantle source for neon. Some crustal input may also be present. The slightly lower-than-mantle He isotopic ratios and the variability in Ne isotopic compositions indicate that these gases may have been impacted by a subduction-related crustal component during the Variscan (or Hercynian) Orogeny. 40Ar/36Ar ratios are higher than atmospheric levels and arrive up to 4680, indicating a mixture of atmospheric and mantle sources. Thermobarometry of pyroxene mineral grains reveals temperatures and pressures suggesting that the crystallization started at ~75 km depth and ended at ~20 km depth following a smooth p-T course. This implies diverse magma ascent conditions. A total of 56 gas samples were collected from two intensively degassing areas in the western Eger Rift (Czech Republic), namely the mofette fields of Bublák and Hartoušov. From the Hartoušov mofette field, 24 gas samples of fluids ascending in two boreholes (F1:∼28 m depth and F2: ∼108 m depth) and 22 samples of gases emerging in two nearby ponds [surface expressions Hartoušov Mofette (HM) and Hartoušov Mofette South (HMS)] were taken. Ten samples were collected from a pond in the Bublák mofette field (Bbl). In addition to the gas samples, ten rock samples were collected from rock exposures [i.e. Libá (LI) and Číhaná (CI) in quarries, Horní Slavkov (HS1&2), Pila (PI), Dolní Dražov (DD), Kadaň (KN), Horní Paseky (HP), and Slapany (SL) in natural cliffs, and Hlinky (HL) in an outcrop] within the western Eger rift area. In addition, six samples of ultramafic nodules/xenoliths were obtained from the Quaternary tephra deposit of the Mýtina maar and from Železná hůrka scoria cone. Gas and rock sampling:

The noble gas isotopic composition of the upper mantle in non-arc oceanic settings: Inferences from fluid inclusion studies

OIB localities (e.g., Tristan, Samoa) have been considered ideal natural laboratories for studying mantle heterogeneity. Indeed, Sr, Nd, and Pb isotopes of lavas collected from OIB systems have provided insights into the existence of distinct mantle reservoirs, the origins of which are closely related to local tectonic processes: DMM, HIMU, EM1, and EM2. In this context, we aim to investigate the isotopic composition of noble gases in fluid inclusions trapped in xenoliths and lavas from Samoa and Tristan islands, two well-known enriched mantle (EM) localities. Our goal is to evaluate the role of noble gas cycling and active tectonic processes on the composition of the upper mantle. Our results show that CO2 is the most abundant volatile in all samples (lavas and xenoliths) from both localities. The 4He/20Ne ratio in most samples is lower than 150, suggesting the presence of atmospheric components in the fluid inclusions. This is further confirmed by the relatively low 40Ar/36Ar ratios, particularly in Tristan samples, which show values below 360. It is worth noting that the Samoa sample exhibits a 40Ar/36Ar ratio of 1000.4, the highest of the dataset. The Rc/Ra values (3He/4He corrected for atmospheric contamination) observed in the Samoa samples align with the Ar ratios mentioned above, as the 3He/4He ratio is the highest reported (13.32Ra). This is above the MORB range, indicating a contribution from lower mantle fluids, likely derived from the Samoan hotspot. In contrast, Tristan samples exhibit low Rc/Ra values, with an average of 5.12Ra. These low helium ratios suggest the presence of a more radiogenic, 4He-rich mantle. The low helium ratios may be related to the EM nature of the mantle. Previous studies in the Canary Islands have shown a decrease in 3He/4He ratios in the eastern part of the archipelago, where EM components have been identified (Hoernle et al., 1993; Simonsen et al., 2001; Day and Hilton, 2011, 2021; Sandoval-Velasquez et al., 2021). However, it is confirmed that an EM component can show a wide range of variation for the 3He/4He ratio, ranging from low values of 5-6Ra to values beyond the typical MORB range, which overlaps (and complicates the distinction) with other OIB contexts with HIMU signature. This publication results from work conducted under the transnational access/national open access action at INGV-Palermo- Noble gas laboratory supported by WP3 ILGE - MEET project, PNRR - EU Next Generation Europe program, MUR grant number D53C22001400005.

Geochemical data on silicon isotope and Ge/Si ratios along a global erodosequence

We provide geochemical data for three sites that define a gradient of erosion rates – an “erodosequence”. These sites are the Swiss Central Alps, a rapidly-eroding post-glacial mountain belt; the Southern Sierra Nevada, USA, eroding at moderate rates; and the slowly-eroding tropical Highlands of central Sri Lanka. Specifically, we provide silicon isotope ratios and germanium/silicon ratios and the major element composition of 1) rock, 2) saprolite, 3) soil, 4) plants, 5) river dissolved loads, 6) the soil and saprolite amorphous silica fraction (accessed with a NaOH leach), and 7) the soil and saprolite clay-size fraction (isolated with a differential settling protocol). These data serve two purposes. First, they allow us to improve understanding of the controls on silicon isotopes and germanium/silicon ratios in the 'Critical Zone'. Specifically, we can quantify the fractionation factors (for silicon isotopes) and the exchange coefficients (for germanium/silicon ratios), for secondary mineral precipitation and for biological uptake. Secondly, we can use mass-balance approaches to quantify the partitioning of silicon - a nutrient, and a major rock-forming element - among secondary minerals, plant material, and solutes. All samples are assigned with International Geo Sample Numbers (IGSN), a globally unique and persistent Identifier for physical samples. The IGSNs are provided in the data tables and link to a comprehensive sample description.

Denudation and weathering rates of carbonate landscapes from meteoric 10Be/9Be ratios

We provide sample information and geochemical data for obtaining erosion, weathering, and denudation rates from a framework based cosmogenic meteoric 10Be versus stable 9Be (10Be/9Be) ratios. We modified this published silicate framework (von Blanckenburg et al., 2012) to carbonate landscapes, and performed thorough ground-truthing and testing of assumptions, as this is the first application of the framework for carbonate lithologies. The most important methodological findings are as follows: 1) We amended a sequential extraction step specific for solubilizing total carbonate-bound Be using acetic acid. As this extraction cannot distinguish between secondary and primary carbonate, we employed carbon stable isotopes to obtain the fraction of Be associated with secondary carbonate. We find that >90% of total carbonate-bound Be is bound to secondary carbonate, meaning that distinguishing between secondary and primary carbonate and employing carbon stable isotopes may not be necessary. 2) Using radiogenic strontium isotope ratios we found that about a third of the 9Be contained in secondary carbonate is derived from the dissolution of silicate phases, likely clastic impurities such as clays. These silicate phases also adsorb meteoric 10Be during weathering. The method is thus applicable to pure limestone as well as mixed carbonate-siliciclastic lithologies. 3) Total 9Be concentrations in bedrock are heterogeneous in the Jura, and are potentially controlled by the amount of silicate impurities contained in limestone. Yet the average 9Beparent in summed carbonate- and silicate-bound fractions (0.07 ug/g) is about 9 times lower than values from existing rock databases. In limestones studies, 9Beparent must be thus determined case-by-case on local bedrock. 4) The analysis of partition coefficients Kd for 10Be and 9Be, respectively, and very similar 10Be/9Be ratios show that dissolved Be has equilibrated between reactive (amorphous and crystalline Fe-oxides) and secondary carbonate phases. Secondary carbonate phases are thus part of the reactive Be pool in limestone settings. 5) As in previous studies in silicate lithologies 10Be and 9Be concentrations show pronounced differences between soil and sediment samples that we attribute to grain size dependence and sorting. The 10Be/9Be ratios however cover a remarkably narrow range for all samples, resulting a in narrow range in denudation rates. 6) The fraction of 9Be released by weathering and partitioned into the secondary reactive or dissolved phase serves as a Be-specific proxy for the degree of weathering. 7) The atmospheric depositional flux of 10Be estimated for the Jura mountains from concentrations of dissolved and particulate 10Be and river gauging is about 80% of estimates from independent global GCM-based distribution maps. The GCM estimates thus provide sufficient accuracy. From application of these new principles, weathering and erosion in the French Jura Mountains can be described as follows: The proportion of weathering in total denudation W/D is >0.9, due to the high purity of the limestone that almost completely dissolved except for a small silicate mineral fraction that, however, carries 50% of the bedrock’s 9Be. Resulting 10Be/9Be-derived denudation rates are on average 300 t/km2/yr for soils and 580 t/km2/yr for river sediments. The soil-derived values agree well with previous estimates from gauging data despite their entirely different (decadal vs. millennial) integration time scales. That sediment-derived denudation rates exceed those from soil we attribute to a 30-60% contribution from subsurface bedrock weathering. On a global scale, our data provides the first cosmogenic-based denudation rates for the precipitation (MAP) range of 1200 to 1700 mm/yr under a temperate climate and dense vegetation cover. Previous millennial-scale denudation rates from in situ-36Cl in calcite from less vegetated sites do not exceed 250 t/km2/yr in this precipitation range. With 500-600 t/km2/yr our denudation rates peak at MAP of 1200-1300 mm/yr, and then show a trend of decreasing D with increasing MAP.

Ruthenium and Tungsten isotopic composition of ocean island basalts and refrence materials

The dataset includes Ruthenium and Tungsten isotope data for mafic to ultramafic lava associated with the Hawaii, Réunion, Galápagos and Iceland plume systems. The data is supplemented by Ru isotope data for reference materials (OREAS 684) picrite derived from the upper mantle (Gönnern Quarry, Hessia) lherzolite preidotites (Eifel) and Eoarchean dunites (Isua, Greenland). The data are supplementary to: Messling, Nils; Willbold, Matthias; Kallas, Leander; Elliott, Tim; Fitton, J. Godfrey; Müller, Thomas; Geist, Dennis (submitted) Core leakage revealed by Ru and W isotope systematics in ocean island basalts. Submitted to Nature

Geochemical, isotopic, geochronological data and assimilation plus fractional crystallization model of The Pleiades Volcanic Field (Northern Victoria Land, Antarctica)

This dataset presents a set of geographical, geochemical and isotopic data, microphotos of thin sections and geochemical binary variation diagrams of sixteen samples of volcanic rocks collected in The Pleiades Volcanic Field, Northern Victoria Land, Antarctica (≈ 72° 42’ S; 165° 43’ E), made up of some 20 monogenetic, partly overlapping scoria and spatter cones, erupted in the last 900 ka, cropping out from the ice close to the head of Mariner Glacier. First two files of dataset (kmz files) contain locations of volcanic centres of The Pleaides Volcanic Fiels and the locations of the collected samples. File #3 contains analytical results of full major element, trace element and radiogenic (Sr, Nd, Pb) isotopic data of collected samples. File #4 contains analytical details of Ar-Ar geochronological data. File #5A and 5B contains modelling results, respectively, of major elements and trace elements-Sr isotope ratios of Assimilation plus Crystal Fractionation (AFC) applied to selected samples of The Pleiades Volcanic Field. Other files are images containing high-resolution pictures collected through optical microscopy of thin sections of collected samples showing their most important petrographic features and binary geochemical diagrams of variation of major elements and selected trace elements against SiO2 (wt%). This data are supplement to a manuscript currently submitted to G3 – Geochemistry, Geophysics, Geosystems, and are used to describe the main petrographic and geochemical features of the volcanic products outcropping at the Pleiades, define the characters of their mantle source, to define their evolutionary patterns. Through these data, we observed an unusual fractionation trend for this kind of volcanic fields, with a large assimilation rate of crustal material, ane we hypothesize a role of the thick-ice cap able to suppress the eruption potential and to increase the residence times of magma in crustal chambers.

GEOSCRAPE zircon database

This database contains a compilation of published zircon geochronology, chemistry and isotope data. The database was created through automated web scraping of the Figshare data repository. Data included U-Pb and Pb-Pb dating, Lu-Hf isotopes, trace element and rare earth element chemistry and isotopes. Where available, metadata on the analytical method, lithology, sample description and sampling coordinates are included. All analyses include a citation and doi link to the original data hosted on Figshare. See metadata table for descriptions of table headers. See associated manuscript for web scraping code.

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