Mantle Archives

Towering black smoker chimneys belch superheated water rich in chemicals and minerals. Bacteria transform this toxic soup into energy, kickstarting an astonishing community of life. Image courtesy of ROV SuBastian/Schmidt Ocean Institute

Expedition Led By MBARI Researchers Reveals A Remarkable, And Rare, Form Of Deep-sea Hydrothermal Vents

by Keith CowingJuly 10, 2026July 10, 2026

[MBARI] An international team of researchers, led by MBARI Senior Scientist Aaron Micallef and Schmidt Ocean Institute, has discovered two remarkable fields of hydrothermal vents in the Doldrums Megatransform and […]

Sensitivity of the Fe anomaly of the overturned silicate layer with respect to the rest of the mantle. (a) Sensitivity of this anomaly vs. mantle thickness. Mars and Earth sizes are represented for clarity. Note that the final anomaly is expected to be maximum when the thickness of the mantle is that of the critical Rayleigh number DRac and tends to 0 at infinite thickness. (b) Sensitivity of the Fe# anomaly vs. the bulk Fe# of the mantle. Earth and Mars compositions are represented for clarity. We extend compositions to lower bulk Fe# than Earth according to (R. J. Spaargaren et al. 2023) (dotted line, see text). All other properties remain fixed at Earth-like values except for gravity acceleration which is scaled linearly to planet size (assumed to be proportional to mantle thickness). The density anomaly secondary axis is valid for both, panel (a) and (b). -- astro-ph.EP

Astrogeology, Biogeochemical Cycles & Geobiology, Mapping, Geodesy, Cartography, Bathymetry, Mars, Press Release

Earth And Mars Interior Structures Set By Re-melting Of The First Solid Mantle

by Keith CowingMay 8, 2026May 8, 2026

Magma ocean crystallisation sets up the early structure and long-term evolution of terrestrial planets. Recent seismic evidence signals the presence of a silicate layer at the base of Mars’ mantle.

Iron isotopic compositions of CI chondrites, CV chondrites, and terrestrial rocks. The μ 54Fe and μ58Fe data for different sample types (see legend) from this study (solid symbols) together with data from previous works (open symbols) (Table S1). Error bars indicate 95% confidence intervals. CV chondrites have similar μ 58Fe but elevated μ 54Fe compared to terrestrial samples. CI chondrites have similar μ 54Fe but elevated μ 58Fe compared to terrestrial samples. -- astro-ph.EP

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Meteorites & Asteroids, Press Release

Iron Isotope Anomalies And The Origin Of The Earth

by Keith CowingMarch 30, 2026March 30, 2026

Understanding the origin of the Earth requires determining the original formation location of its building material.

Summary of the geodynamic, topographic, climatological, and biogeographical evolution of the system. Regional paleogeography with profiles showing mantle density anomalies from Straume, et al. 68 -- Nature .

Astrogeology, Biogeochemical Cycles & Geobiology, Gaia - Planetary Perspectives, Origin & Evolution of Life, Press Release, Tethys

How Earth’s Mantle Activity Drove Humans And Animals Into Asia And Africa

by Keith CowingApril 22, 2025October 7, 2025

What roils beneath the Earth’s surface may feel a world away, but the activity can help forge land masses that dictate ocean circulation, climate patterns, and even animal activity and […]

Astrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Caves, Craters, Mountains, Subsurface, Lava Tubes, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Lava / magma ocean / Volcanic Worlds, Status Report

Chemical Evolution Of An Evaporating Lava Pool

by Keith CowingNovember 24, 2024November 24, 2024

Many known rocky exoplanets are so highly irradiated that their dayside surfaces are molten, and `silicate atmospheres’, composed of rock-forming elements, are generated above these lava pools.

Compositions of igneous rocks from Earth, the Moon, Mars, and other differentiated bodies. The data shown are relatively comprehensive, giving a good indication of the distribution of rock compositions. Sources: Earth – IGBADAT5 from IUGS; Moon – MoonDB (moondb.org); Mars – Filiberto et al. 2017; Achondrites – Kimura et al. (2018)

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Lava / magma ocean / Volcanic Worlds, Press Release, Water/Hycean Worlds & Oceanography

Scientists Compile Library For Evaluating Exoplanet Water

by Keith CowingNovember 15, 2024November 15, 2024

By probing chemical processes observed in the Earth’s hot mantle, Cornell scientists have started developing a library of basalt-based spectral signatures that not only will help reveal the composition of […]

Upper panels: The peak hydrogen envelope mass fraction at the end of accretion, before any mass loss, shown in colour for the slow, medium and fast host star rotators. The time when 90% of the envelope mass is lost due to solar XUV radiation is shown in white contour lines in Myr. Lower panels: The atomic composition of the outgassed atmospheres of the slow, medium and fast rotator simulations at 300 Myr. Values of R/O < 1 (blue) indicate an atmosphere with free oxygen, a value of R/O=1 (green) imply sufficient oxygen to oxidise H to H2O and C to CO2, and values of R/O > 1 (red) indicate reducing conditions (see definition of R/O in equation 8). The white contour lines in the lower panels show a value of R/O = 1.3. The patch of R/O=0 present for the slow rotator is due to the perseverance of the envelope for those high planetary masses even after 300 Myr, with the magma ocean still providing a significant pressure of free oxygen. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones, Lava / magma ocean / Volcanic Worlds, Meteorites & Asteroids, Status Report, Water/Hycean Worlds & Oceanography

Evolution of Gas Envelopes and Outgassed Atmospheres of Rocky Planets Formed via Pebble Accretion

by Keith CowingSeptember 18, 2024September 18, 2024

We present here results of numerical simulations of the formation and early evolution of rocky planets through pebble accretion, with an with an emphasis on hydrogen envelope longevity and the […]

The researchers say the rocks recovered from the mantle bear a closer resemblance to those that were present on early Earth rather than the more common rocks that make up our continents today. CREDIT Professor Johan Lissenberg

Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Fossils & Paleontology, Habitable Zones, Press Release

Rocks From Earth’s Mantle Could Reveal Geological History

by Keith CowingAugust 12, 2024August 12, 2024

Scientists have recovered the first long section of rocks that originated in the Earth’s mantle, the layer below the crust and the planet’s largest component. The rocks will help unravel […]

(a) Formation process of the ribose from 10 (Z)-ethene-1,2-diol, 5 formaldehyde, and 5 water under the condition of 10 GPa - 1400 K. (b) Free energy landscape for analyzing the formation process of ribose, as a function of two kinds of C-C distance as the collective variables. To better distinguish the selected carbon atoms, C1 and C2 are marked by yellow and orange colors, respectively. (c) The evolution process of the ribose from the open chain to a five-membered ring (10 GPa - 1400 K). (d) Comparison of the formation ability of five-membered ring and sixmembered ring based on the free energy calculation with the C-O distance as the collective variable. -- physics.bio-ph

Astrogeology, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Extremeophiles and Extreme Environments, Fossils & Paleontology, Habitable Zones, Status Report, Water/Hycean Worlds & Oceanography

Synthesis And Stability Of Biomolecules Under Earth’s Upper Mantle Conditions

by Keith CowingMay 9, 2024

How life started on Earth is a long-time unsolved mystery. There are various hypotheses ranging from outer space to seabed.

Distributions in viscosity, density and thickness for 5-layer profiles, meeting both geophysical and thermal constraints, without (upper row) and with (lower row) BML. The grey zones picture the exploration priors taken for each of the parameters after filtering with mass and moment of inertia. -- astro-ph.EP

Astrogeology, Biogeochemical Cycles & Geobiology, Mars, Status Report

Coupled Geophysical And Thermal Constraints Link Between Mars Basal Molten Layer And The Planet Viscosity Profile

by Keith CowingMarch 12, 2024March 12, 2024

Computing the tidal deformations of Mars, we explored various Mars internal structures by examining profiles that include or exclude a basal molten layer within the mantle and a solid inner […]