Childs completed his undergraduate degree at 51ÁÔÆæ before returning to work on his Master\u2019s. He studies planetary geology, and he\u2019s especially interested in what minerals may be present on the surface of Venus.<\/p>\n\n\n\n
To find out, he visited lava tubes in Hawaii.<\/p>\n\n\n\n \u201c(Lava tubes) look just like cave systems,\u201d Childs explained. \u201cWhen you have lava flowing down the slopes of a volcano, it can channel and produce a river. The outer surface of this river is exposed to the cooler atmosphere and will solidify first \u2026 and can form a roof for the still hot, still flowing, lava interior.\u201d<\/p>\n\n\n\n Over time, he added, the lava will wear through the earth beneath it, leaving behind a cavern. Lava tubes remain insulated from the air on Earth\u2019s surface and can maintain their superheated environment for months to years later.<\/p>\n\n\n\n \u201cFor my (research), we wanted to see what minerals grow in this environment in these caves and see, do they grow in a hot environment and a dry environment?\u201d Childs said.<\/p>\n\n\n\n Childs collected mineral samples from chunks that had broken off the sides and ceilings of the lava tubes \u2013 areas that would have been exposed to the heat of the lava without being under the lava. Then, he took them back to the lab at 51ÁÔÆæ for analysis. With x-ray diffraction, he could identify the secondary minerals present in his lava tube samples \u2013 hematite, magnesioferrite, cristobalite, tridymite, and gypsum.<\/p>\n\n\n\n Then, using other methods like visible near infrared spectroscopy and scanning electron microscopy, Childs began to infer the processes under which those minerals formed. He found that the surface of his samples were entirely composed of metal ions, while the interior looked more like a normal basalt rock. That meant there was evidence of a process called \u201cmetal migration.\u201d Essentially, Childs said, the high temperatures created a powerful oxidizing environment, which pulled out electrons and fed more metal ions to the surface of the rock to compensate for the change in charge.<\/p>\n\n\n\n His work shows that some of these minerals do form in hot, dry environments, and that Venus may therefore have similar minerology. Childs can\u2019t say how close the lava tubes are to conditions on Venus, but \u201cdefinitely we\u2019re on to something here.\u201d<\/p>\n\n\n\n Magnets in lava tubes<\/strong><\/p>\n\n\n\n If Childs is interested in minerals, then Terra Johnson is interested in their magnetism. Johnson, who uses they\/them pronouns, is an undergraduate researcher majoring in geosciences. They are set to graduate this May and plan to attend 51ÁÔÆæ for graduate school next year.<\/p>\n\n\n\n Their research seeks to uncover the varying types and abundance of magnetic minerals that are found in oxidized versus unoxidized environments \u2013 i.e., inside of the lava tubes versus outside of them.<\/p>\n\n\n\n \u201cWhen you have an oxidized sample, as Dylan was explaining, you would expect more iron-rich minerals, or more magnetic minerals like hematite, on the surface (of the sample),\u201d Johnson said.<\/p>\n\n\n\n To find those minerals, Johnson borrowed Childs\u2019 samples from the lava tubes and measured their coercivity. This measures a magnetic material\u2019s ability to resist an external magnetic field and retain its original alignment. Certain materials have higher coercivities than others. By determining coercivity, Johnson can make a guess as to what minerals are present in the samples, and how much of them there are.<\/p>\n\n\n\n \u201cSo if I\u2019m a hematite grain pointing one way, I need a much stronger field to flip my magnetic direction the other way than if I was magnetite,\u201d they explained. \u201cSo we can do those tests, and I\u2019ll have graphs with a huge curve showing low coercivity minerals, which are probably more magnetite, and then a smaller curve with higher coercivity, which is more like hematite.\u201d<\/p>\n\n\n\n They compared samples taken from the inside and outside of the lava tubes, and found that the samples from inside \u201chad a much more complicated magnetic profile than the stuff outside,\u201d which is a good indicator of the presence of an oxidative environment.<\/p>\n\n\n\n Johnson said that their research adds to the body of Childs\u2019 work, and could help explain why there is a reddish color to Venus\u2019 surface \u2013 perhaps there is a hematite or iron oxide product present.<\/p>\n\n\n\n Childs and Johnson presented their research at the Geosciences Research Symposium in March, and their work adds to a growing body of knowledge about Venus. This type of research is important, Johnson said, because the more we can understand about Earth\u2019s twin and why it\u2019s so different from Earth, the more we can understand about how planets form, evolve, and thrive \u2013 or die.<\/p>\n\n\n\n By Sarah Vickery, College of Letters & Science<\/em><\/strong><\/p>\n","protected":false},"excerpt":{"rendered":" Mars seems to get all the attention when it comes to interplanetary study, but Earth has another neighbor that\u2019s shrouded in mystery \u2013 and a thick layer of yellow clouds. Venus is a barren, rocky planet that has long fascinated …<\/p>\n","protected":false},"author":785,"featured_media":27491,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":"","uwm_wg_additional_authors":[]},"categories":[1648,1945,1846],"tags":[1854],"class_list":["post-27490","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-in-focus","category-in-focus-2024","category-research-news","tag-april"],"yoast_head":"\n![\"A](\"https:\/\/uwm.edu\/letters-science\/wp-content\/uploads\/sites\/255\/2024\/03\/Dylan-Childs-lava-tube-300x200.webp\")
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