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.

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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. 

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Do Microbes Release Fluorine from Rocks?

Image of soil microcosm

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. 

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