{"id":471690,"date":"2026-02-13T04:56:12","date_gmt":"2026-02-13T04:56:12","guid":{"rendered":"https:\/\/www.newsbeep.com\/ca\/471690\/"},"modified":"2026-02-13T04:56:12","modified_gmt":"2026-02-13T04:56:12","slug":"look-again-those-wrinkly-rocks-may-actually-be-a-fossilized-microbial-community","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/ca\/471690\/","title":{"rendered":"Look again! Those wrinkly rocks may actually be a fossilized microbial community"},"content":{"rendered":"

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\"Wrinkle<\/p>\n

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image:\u00a0<\/p>\n

The outcrop in Morocco where Associate Professor Rowan Martindale noticed the wrinkle structures formed by microbial communities. Note that the large ripples on the rock slab were formed by turbidity currents. The wrinkle structures are a more subtle texture that overlays the larger ripples.<\/p>\n

view more\u00a0<\/a><\/p>\n

Credit: Rowan Martindale \/ UT Jackson School of Geosciences<\/p>\n

In 2016 while hiking on a hillside in Morocco, geologist Rowan Martindale saw something that made her stop in her tracks: a slab of sedimentary rock covered in a wrinkly texture reminiscent of elephant skin.\u00a0<\/p>\n

\u201cI looked at the wrinkles and I was like, \u2018These aren\u2019t supposed to be in rocks like this. What the heck is going on?\u2019\u201d said Martindale, an associate professor at The University of Texas at Austin\u2019s Jackson School of Geosciences.<\/p>\n

Rock textures hold clues about the geological activity that shaped them. To Martindale, these wrinkles in time were a textbook example of microbial mat fossils. They captured a teeming community of bacterial ooze that lived over 180 million years ago during the Early Jurassic.<\/p>\n

She had seen dozens of photographs and samples that had the same texture as the slab while in graduate school, thanks to a lab mate who had specialized in microbial fossils from the Early Triassic age.<\/p>\n

There was just one problem: the geologic setting was all wrong.<\/p>\n

The sediment where the wrinkles had formed was originally from the deepwater ocean, almost 600 feet below the surface. But the prevailing explanation in the geological community was that the wrinkle structures made by microbes were limited to shallow water environments in stressful settings or after extinction events \u2013 both situations where the microbes would have access to sunlight and be free from marine life that would readily gobble them up.<\/p>\n

For deepwater settings, the usual explanation for wrinkle-like textures was impressions made be an underwater landslide, which pushed sediment around into ridges and furrows. But Martindale didn\u2019t buy it. The wrinkles in the hillside had that microbial look.<\/p>\n

\u201cIt was one of those things, knowing what to look for and having that \u2018search image\u2019 of wrinkle structures in my head, that made me want to stop and dig into this,\u201d she said.<\/p>\n

In a recent paper published in Geology<\/a>, she and her co-authors propose a new explanation for the wrinkle structures that unites the worlds of biology and geology. The wrinkles weren\u2019t formed by physical forces during an underwater landslide \u2014 but the landslide did set the stage for the microbes to grow by transporting nutrients to the ocean floor.<\/p>\n

In their paper, the researchers propose that the wrinkles were formed by a micr\u00adobial mat that sustained itself with nutrients swept to the ocean depths by the landslide rather than sunlight, a mode of making energy called chemosynthetic. \u00a0Their intake of chemicals may have also enabled these microbial communities to emit toxic sulfur compounds that would have kept sea life at bay.<\/p>\n

There are microbial communities found in ocean depths today that live in a similar manner, such as the microbial mats that coat whale carcasses that drift down to the seafloor and help seed rich and ephemeral \u201cwhale fall\u201d ecosystems.<\/p>\n

Jake Bailey, a professor at the University of Minnesota who studies how microbes shape the Earth\u2019s environment, said the research upends assumptions about ancient wrinkle structures being from just one type of microbial community.<\/p>\n

\u201cIn the present, some of the largest microbial ecosystems on our planet are found in the dark ocean,\u201d said Bailey, who was not involved with the research. \u201cThe research here shows that certain ancient sedimentary structures may record the presence of these chemolithotrophs rather than phototrophs (organisms that need sunlight to make energy). \u201d<\/p>\n

Martindale said that the finding is important because it suggests that fossils of chemosynthetic microbial communities might be more prevalent in the fossil record than previously thought. What\u2019s more, a bias for interpreting wrinkles as purely physical structures could lead to geoscientists misclassifying fossils as natural formations. This bias is worsened by the lack of specific language for describing wrinkles in rock.<\/p>\n

\u201cThe terminology is pretty lax,\u201d Martindale said. \u201cWrinkly can be mean lots of things, so there\u2019s a lack of diagnostic language.\u201d<\/p>\n

Martindale\u2019s usual research focus is ancient coral reefs and mass extinctions. She wasn\u2019t expecting to go on a research detour into deep-sea microbial mats. But when a vexing question appears under your nose, sometimes you have to see where the science leads.<\/p>\n

\u201cIt\u2019s really cool to have gone in this direction that I totally wasn\u2019t expecting,\u201d she said. \u201cThere was no hypothesis that I would find these microbial mats here. It was just being in the right place at the right time, with the right search image. And then being so stubborn as to not let go of it.\u201d<\/p>\n

The research was funded by the National Science Foundation.<\/p>\n

Article Title<\/p>\n

Chemosynthetic microbial communities formed wrinkle structures in ancient turbidites<\/p>\n

Article Publication Date<\/p>\n

3-Dec-2025<\/p>\n

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.<\/p>\n","protected":false},"excerpt":{"rendered":"image:\u00a0 The outcrop in Morocco where Associate Professor Rowan Martindale noticed the wrinkle structures formed by microbial communities.…\n","protected":false},"author":2,"featured_media":471691,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[49,48,66],"class_list":["post-471690","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-ca","tag-canada","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/471690","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=471690"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/471690\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/471691"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=471690"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=471690"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=471690"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}