Results 111 to 120 of about 257,482 (231)

Lithological Controls on Aqueous Phosphorus on Ocean-covered Exoplanets

The Planetary Science Journal
On Earth, weathering of subaerial continental crust is necessary for the delivery of phosphorus (P)—a critical nutrient for life—to the oceans. However, P inputs, and therefore the potential for nutrient limitation on biological productivity, must be ...
Adam T. Stone, Bradford J. Foley, Benjamin M. Tutolo, Kimberly V. Lau   +3 more
doaj   +1 more source

SC‐550: A Sintered Calcite Reference Material for In Situ U‐Pb Geochronology

Geostandards and Geoanalytical Research, EarlyView.
Key Points New calcite reference material (SC‐550) produced by high‐temperature and high‐pressure sintering of nano‐particulate powder from a microbial limestone. Homogeneous U content (2.3 ± 0.4 μg g‐1) and U‐Pb isotope ratios (< 0.6% RSD for 207Pb/206Pb; < 3% RSD for 238U/206Pb).
Lorenzo Tavazzani, Nico Kueter, Dawid Szymanowski, Felix Marxer, Ismay Vénice Akker, Marcel Guillong, Massimo Chiaradia, Yannick Buret   +7 more
wiley   +1 more source

Metamorphic or Igneous Zircon? Classification Through Rare Earth Elements, Machine Learning and Logistic Regression

Journal of Metamorphic Geology, EarlyView.
ABSTRACT Zircon is a common, highly refractory accessory mineral found in sedimentary, igneous and metamorphic rocks that forms through various processes (e.g., magmatic, hydrothermal, metamorphic growth and recrystallization). Trace element compositions of detrital zircon have been widely applied to understanding tectonic processes and continental ...
Jarrod M. Burges, Chris Yakymchuk, Michael P. DiMaio, Timothy C. C. Lui, Anirudh Prabhu, Shaunna M. Morrison   +5 more
wiley   +1 more source

Autonomous Detection of Mineral Phases in a Rock Sample Using a Space-prototype LIMS Instrument and Unsupervised Machine Learning

The Planetary Science Journal
In situ mineralogical and chemical analyses of rock samples using a space-prototype laser ablation ionization mass spectrometer along with unsupervised machine learning are powerful tools for the study of surface samples on planetary bodies.
Salome Gruchola, Peter Keresztes Schmidt, Marek Tulej, Andreas Riedo, Klaus Mezger, Peter Wurz   +5 more
doaj   +1 more source

Planetary Geologic Mappers Annual Meeting : June 12-14, 2018, Knoxville, Tennessee [PDF]

, 2018
The annual Planetary Geologic Mappers meetings are held to allow geologic mappers of funded NASA geological mapping projects or other mapping projects to present the status of mapping efforts and obtain guidance for map process, formatting, submission ...

core  

Photochemical effects of Mars‐like UV irradiation on carboxylic acids in carbonaceous chondrites and expectations for abiotic background organics on Mars

Meteoritics &Planetary Science, EarlyView.
Abstract In the search for life on Mars, understanding the origin of preserved organics is critical. Expected sources include exogenous delivery, endogenous synthesis, and potentially life. Environmental processing by ultraviolet (UV) irradiation can alter these organics, obscuring hallmarks of their origin. To deconvolve these effects, we conducted an
D. K. Buckner, J. C. Aponte, A. C. Schuerger, D. I. Foustoukos, F. Seguin, M. B. Wilhelm, G. Cooper, A. J. Williams   +7 more
wiley   +1 more source

Description and terrestrial ages of the Calama Area Meteorite Collection (Atacama Desert, Chile)

Meteoritics &Planetary Science, EarlyView.
Abstract We present a comprehensive study of a meteorite collection from the Atacama Desert (Chile), the driest and most climatically stable desert in the world. This collection includes meteorites from three adjacent Dense Collection Areas (DCAs) in the northern part of the Atacama Desert: Calama, Sierra Gorda, and Chug Chug, referred to as the ...
Carine Sadaka, Jérôme Gattacceca, Florian Dumas, Régis Braucher, ASTER Team, Matthieu Gounelle, Dilyara Kuzina, Cyril Lorenz, Alexandre Corgne, Pierre Sempéré   +9 more
wiley   +1 more source

Uranium: mineralogy, geochemistry, and the environment Reviews in mineralogy ;, v. 38./ editors, Peter C. Burns & Robert J. Finch.

, 2018
In English.Includes bibliographical references.Volume 38 of Reviews in Mineralogy provides detailed reviews of various aspects of the mineralogy and geochemistry of uranium.
Finch (Robert James),, Burns Peter C.,
core  

Revisiting olivine‐phyric shergottites: Pyroxene crystallization pressure and the role of undercooling

Meteoritics &Planetary Science, EarlyView.
Abstract Shergottites are the most abundant meteorites from Mars and a major source of information on magma reservoirs, transport, and eruption, particularly in the late Hesperian northern hemisphere. Conflicting interpretations have arisen on the crystallization conditions of pyroxene in olivine‐phyric shergottites.
Roger H. Hewins, Brigitte Zanda, Arnaud Duverger   +2 more
wiley   +1 more source

Empirical evidence for multi-decadal transients affecting geodetic velocity fields and derived seismicity forecasts in Italy

Scientific Reports
This study critically examines the use of geodetic strain rates for forecasting long-term earthquake rates in a slow-deforming region such as Italy, challenging the prevailing assumption of their temporal stationarity in interseismic stages for seismic ...
Michele M. C. Carafa, Peter Bird, Alessandro Verdecchia, Matteo Taroni, Carlo Doglioni   +4 more
doaj   +1 more source