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The depositional flux of meteoric 10Be derived from combined in situ and meteoric 10Be analyses along a climate gradient (Chile)

This dataset contains Beryllium isotope data, pH measurements, and calculations of surface process rates (denudation, weathering, erosion) from soil and drill core samples from the Coastal Cordillera, Chile. All drilling and soil sampling campaigns were conducted in the framework of the “EarthShape” project (DFG SPP1803) from March 2019 to March 2020. Rock and soil samples consist of granitoid lithology that is weathered to different degrees. We measured the concentration of in situ 10Be in quartz samples from soil samples and calculated denudation rates thereof. Furthermore, we applied a sequential extraction method to analyse meteoric 10Be and reactive 9Be; we also measured residual 9Be and parent bedrock 9Be concentrations. Using the concentration of meteoric 10Be, we calculated the inventory assuming exponential decrease with depth. Finally, we calculated the depositional flux using the in situ 10Be denudation rate and the 10Be(meteoric)/9Be isotope ratio. From reactive 9Be, we calculated the fraction of reactive and dissolved 9Be that we interpret as weathering indicator. All samples are indicated with a IGSN (International Generic Sample Number) which is a global unique sample identifier. These IGSNs are provided in the data tables and are linked to a short data description in the internet.

Accessory Minerals in Felsic Igneous Rocks - Part 3: Composition of monazite-(Ce) from Paleoproterozoic granitoids and gneisses from the Fort McMurray area (Alberta, Canada)

This data set is the third of a series reporting chemical data for accessory minerals from felsic igneous rocks. It compiles the results of electron-microprobe spot analyses of monazite-(Ce) from various Paleoproterozoic granitoids and spatially associated gneisses located in the wider Fort McMurray area in northeastern Alberta, Canada. The data were generated in connection with the Master of Science thesis of Nathanial John Walsh (Walsh 2013) at the Department of Earth and Atmospheric Sciences of the University of Alberta, Edmonton, Canada, but remained unpublished. The thesis was part of the Helmholtz - Alberta - Initiative (HAI) between the University of Alberta and the Helmholtz Association.Interestingly, monazite from the diverse basement rocks display various kinds of pattern with respect to composition and origin. The great bulk of measured grains display variably declined chondrite-normalized LREE patterns virtually free of anomalies indicative for significant fluid-induced overprinting. We have rocks characterized by largely unzoned, chemically homogeneous grains. There are as well rocks containing nicely patchy-zoned grains showing a wide range in composition, in particular regarding the Th/LREE proportions. Here, maximum measured Th concentration amounted to 33 wt% ThO2. Incorporation of Th into the crystal structure is almost exclusively governed by the huttonite substitution reaction, i.e., Th^4+ + Si^4+ = REE^3+ + P^5+, as characteristic for this chemical type of granites (Förster 1998). The suite of rocks also included samples containing small-sized inclusions of Th-poor monazite in apatite, which formed in response to metamorphic, fluid-aided dissolution-reprecipitation processes (Harlov and Förster 2003, Harlov et al. 2005). Finally, we have a quartz monzonite containing Th-poor monazite in apatite together with matrix monazite of normal Th concentration, the origin if which is not yet fully resolved (cf. Foerster-2018-004_monazite-alberta-BSE images.pdf. presenting back-scattered electron images of monazite grains). In brief, the data set provides information on several aspects of formation and alteration of monazite in non-metamorphic and metamorphic granite.The data set published here contains the complete pile of data acquired for monazite-(Ce) and back-scattered electron (BSE) images of many of the probed grains. Chemical data are provided as Excel and machine-readable .csv files, which contain the information listed in Table 1 of the data description file. Column headers in red (only in the Excel version) indicate that the data and information provided in these columns is from Walsh (2013). “0.00” means that the concentrations of the respective elements were measured, but were below their limits of detection. Blank boxes in oxide concentrations columns indicate that the respective elements were not sought. The collection of BSE images is presented as pdf.file. The sample and grain numbers are given below each mineral image and are corresponding to the Sample No. and the Grain No. in the data table.The thesis of N. Walsh "Walsh, N.J. (2013) Geochemistry and geochronology of the Precambrian basement domains in the vicinity of Fort MacMurray, Alberta: a geothermal perspective. Master of Science thesis, Department of Earth and Atmospheric Sciences, University of Alberta, Canada" is not available online.

Physical and geochemical data on a drill core from the semi-arid Coastal Cordillera, Chile

This dataset contains petrophysical, geochemical, and mineralogical data from a drilling core from the Coastal Cordillera, Chile. The drilling campaign in the semi-arid field site Reserve Santa Gracia was conducted in the framework of the “EarthShape” project (DFG SPP1803) to study deep weathering along a climate gradient. Previous studies in this area found that the weathering front is located much deeper than expected (Oeser et al., 2018). To explore the weathering profile and the depth of the weathering front, we performed various geochemical, petrophysical, and mineralogical analyses. The drilling campaign was conducted in March and April 2019, using the wireline drilling method with a standard industry truck-mounted PQ3-sized (85 mm core diameter, 123 mm hole diameter) rotary drilling rig (Sondajes Araos E.I.R.L.). A detailed description of the drilling activities is given in Krone et al. (2021). The retrieved core runs with a maximum length of 1.5 m were drilled using potable water, with added contamination control tracer for further microbiological analyses of the rock. As basis for our detailed study of deep weathering we determined the porosity, density, specific surface area, elemental composition, mineralogical composition, Fe oxidation, and the degree of weathering from chemical depletion, volumetric strain, and the weathering rate using the in situ cosmogenic nuclide beryllium-10 (10Be).

U-Pb age, whole rock and mineral composition of the Angicos Plutonism (Angicos Batholith and Poço da Oiticica Stock) from northern Borborema Province, NE Brazil

This dataset comprises new chemical, isotopic and geochronological analyses for 14 samples from the Angicos Plutonism (Angicos Batholith and Poço da Oiticica Stock) from northern Borborema Province, NE Brazil. Whole rock major and trace element compositions as well as mineral oxide compositions for feldspars, biotite, and Fe-oxides. New analyses on 14 samples are presented in the bulk and in-situ data templates developed by EarthChem. A compilation of all new analyses and previous whole-rock data from Jardim de Sá (1994) are also provided. Analyses were carried out at the Geoanalítica Core Facility at the Instituto de Geociências, University of São Paulo, Brazil. The data are reported with the EarthChem/ DIGIS data templates (IEDA, 2022).

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