minerals – Geobites

January 20, 2022January 20, 2022

Hunting for phosphorus on early Earth

Featured Image: A sample of the mineral schreibersite, a possible source of meteoric phosphorus. CC-BY 3.0, via Wikimedia commons.

Paper: Phosphorus mineral evolution and prebiotic chemistry: From minerals to microbes

Authors: Craig R. Walton, Oliver Shorttle, Frances E. Jenner, Helen M. Williams, Joshua Golden, Shaunna M. Morrison, Robert T. Downs, Aubrey Zerkle, Robert M. Hazen, Matthew Pasek

With a swift strike, a match bursts into flame. Life, like the flame, burst into existence almost 4 billion years ago, and as with the sparking of the match, phosphorus was a key ingredient. Phosphorus, element 15, is at the center of energy production in cells, forms cell walls, and provides the backbone for DNA.

January 11, 2022January 11, 2022

Do we need new types of geology to understand exoplanets?

Featuring image: White dwarf make perfect natural mass spectrometer, more powerful as any instrument on Earth. Can they help us to learn about exoplanets? NOIRLab/NSF/AURA/J. da Silva, Creative Common (CC BY 4.0)

Paper: Polluted white dwarfs reveal exotic mantle rock types on exoplanets in our solar neighborhood

Authors: K. D. Putirka and S. Xu

For a long time, geologist were only able to study rocks on the ground. We extended this knowledge to our neighbouring planets. Now finally, scientist have found a way to study rocks from planets far away, using the light of their host stars. And they look very strange.

Over the last 30 years, exoplanets have evolved from mere theory into a fantastic reality. Today we know that nearly all stars host at least one exoplanet and even exoplanets with an Earth-like mass are relatively common. Still, we know very little about the geology of these worlds. In a new study, Keith Putirka and Siyi Xu were able to observe and compare the mineralogy of exoplanets to that of the rocky planets in the solar system. Surprisingly, these exoplanets exhibit types of mineralogy unlike any we have known before.

September 16, 2021September 16, 2021

Mineralogy on other worlds

Featuring image: Titan seen in infrared light. NASA/JPL-Caltech/Stéphane Le Mouélic, University of Nantes, Virginia Pasek, University of Arizona, public domain (CC0)

Paper: Titan in a Test Tube: Organic Co-crystals and Implications for Titan Mineralogy

Authors: M. L. Cable, T. Runčevski, H. E. Maynard-Casely, T. H. Vu and R. Hodyss

Titan, Saturn largest moon, is a strange world. Its surface is covered by ice, dunes and haze of organic molecules and lakes of liquid methane. It even rains. The diversity of surface features may remind us of our own home planet, but the chemistry between these two celestial bodies lies worlds apart.

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July 1, 2021July 1, 2021

Buried treasure in the oceans: chemistry of small deep-sea crystals hints at past carbon cycling

Featured image: Crystals of the mineral barite from the deep ocean (Adapted from Kastner (1999)). These crystals precipitated in ocean sediments and are about 9 million years old, similar in age to some of the barite samples from the study discussed here.

Paper: A 35-million-year record of seawater stable Sr isotopes reveals a fluctuating global carbon cycle

Authors: Adina Paytan, Elizabeth M. Griffith, Anton Eisenhauer, Mathis P. Hain, Klaus Wallmann, Andrew Ridgwell

What do ancient ocean sediments and the walls around x-ray machines have in common? One possible answer? Sometimes the mineral barite is an important part of both! Barite (or barium sulfate) is able to block gamma and x-ray emissions, and therefore is sometimes used in high-density concrete in hospitals and laboratories. In the deep ocean, tiny crystals of barite naturally accumulate on the seafloor over time, particularly in regions ideal for this mineral formation where many decaying remains of organisms sink to the seafloor. The chemistry of this barite can give scientists clues into Earth’s past, which is what Adina Paytan and her colleagues did in this study.

May 12, 2021June 4, 2021

How lightning changes rocks – Reduction of phosphorus minerals

Featured Image: Lightning is a common high energy phenomenon on Earth, like here during a storm over Bucharest, Romania. Image credit: Catalin.Fatu (Wikimedia Commons), CC BY-SA 3.0.

Papaer: Lightning strikes as a major facilitator of prebiotic phosphorus reduction on early Earth

Authors: Benjamin L. Hess, Sandra Piazolo, Jason Harvey

You might think of lightning as a violent and destructive force of nature, but it might have helped to spark life on Earth. The enormous energy released by lightning can weather or even melt rocks. During this short but intense heating phase, the rock’s or soil’s mineralogy changes and a very important element for life becomes available: phosphorus. A group of researches was able to show why the transformation of phosphorus minerals by lightning could have been an important source of this element during Earth’s infancy.

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March 27, 2021March 27, 2021

What Lies Beneath: Tracing Magma Interactions Within Earth’s Crust

Featured Image: Yosemite National Park, California, USA by Thomas H. from Pixabay

Paper: Feldspar recycling across magma mush bodies during the voluminous Half Dome and Cathedral Peak stages of the Tuolumne intrusive complex, Yosemite National Park, California, USA

Authors: Louis F. Oppenheim, Valbone Memeti, Calvin G. Barnes, Melissa Chambers, Joachim Krause, and Rosario Esposito

Earth’s landscapes provide evidence of the geological processes which have shaped it over the past 4 billion years. The Earth’s crust, our planet’s outermost layer, preserves an extensive record of these processes. Within the crust igneous rocks which were once molten at depth and fed active volcanic eruptions, preserve evidence of the inner workings of volcanoes. These inner workings or “magmatic plumbing systems” are the focus of recent work by Oppenheim et al. (2021). In this work, Oppenheim and co-authors studied the crystal record of fossilized plumbing systems in order to provide new insights into the storage conditions and transport mechanisms of magma within Earths’ crust.

September 16, 2020September 16, 2020

Got an apatite for minerals? Of quartz you do!

Minerals, those naturally occurring, inorganic materials with well-defined chemical compositions and crystal structures have long influenced human culture and fascinated (geo)scientists. Some of the earliest descriptions of minerals and their uses date back to Ancient Egypt, recorded on papyri, as well as on stelae (blocks of stone or wood), and ostraca (clay tablets or pottery shards). Minerals and their uses have been intertwined with human history for thousands of years from the gemstone bracelets of the Egyptians and their belief that color was a strong reflection of personality (color symbolism, e.g., the use of gold for crowns on pharaohs and its association with the sun), to the Greeks and their wide use of gemstones in necklaces, and bracelets.

August 28, 2020August 30, 2020

Do Microbes Release Fluorine from Rocks?

Featured Image used with permission of photographer (Cassi Wattenburger)

Paper: Indigenous microbes induced fluoride release from aquifer sediments

Authors: Xubo Gao, Wenting Luo, Xuesong Luo, Chengcheng Li, Xin Zhang, Yanxin Wang

My science textbook taught me that fluorine (F) was really important for dental health, and I’ve since learned that both excessive and insufficient amounts of fluoride in groundwater can cause health issues. While the chemistry behind the release of fluoride ions from rocks or sediments into groundwater is well understood, the microbiology of this process is not. Specifically, scientists have been wondering whether microbes could speed up the release of F from sediments into groundwater.