From The Arizona State University: “Serpentine rocks provide evidence of fossil life on Earth”

From The Arizona State University


In the Hajar Mountains of Oman is a large slab of oceanic crust consisting of serpentinized ultramafic rocks, the largest exposure of such rocks on Earth’s surface. These distinctive rocks hold fossil evidence of microbes that were once living in the underground environment where these rocks form.

A team of scientists from Arizona State University, led by Jon Lima-Zaloumis, ASU PhD graduate and current postdoctoral research scholar at the School of Earth and Space Exploration, participated in the Oman Drilling Project (OmanDP) and were able to investigate drill core samples of the Samail Ophiolite. By studying these samples in detail using instruments available at ASU and abroad, the team was able to uncover fossil evidence of microbes that were once living and subsequently entombed in the underground serpentinizing environment.

A white, mineralized vein in serpentine drill core preserves fossil evidence of microbes once inhabiting the subsurface. Credit: ASU.

For Lima-Zaloumis, this work is noteworthy because there have been relatively few publications exploring whether microbes can be preserved in environments where serpentine rocks form. 

“Researchers are interested in these systems from an astrobiology perspective because microbes can thrive from the water-rock reactions associated with serpentinization,” said Lima-Zaloumis. “Although we know these systems can host active microbial ecosystems, it’s been unclear whether these systems can also lead to fossilization.” 

This is significant because it highlights a unique geological environment where ancient evidence of life may be detected on Earth and potentially beyond. The results of their findings have been recently published in Nature Communications Earth & Environment [below], with lead author Lima-Zaloumis and co-author Maitrayee Bose, assistant professor in ASU’s School of Earth and Space Exploration. 

“Our work may be helpful for current and future planetary exploration missions with astrobiology-oriented objectives, and highlights the importance of serpentine rocks as targets for future exploration,” said Lima-Zaloumis. “For example, serpentine has been detected from orbit within and around Jezero Crater, the site of the current Perseverance rover on Mars. If such rocks are encountered by the rover, our work emphasizes that they might be prime targets to search for evidence of past life.” 

Lima-Zaloumis and his team spent several months searching for signs of life within these samples, which entailed long hours at the microscope and scanning electron microscope. They suspected that if any evidence of life would be found, it would occur within mineral-filled fractures that were common in the upper portions of the drill core (visible in the above images). 

The team had an “aha” moment when they eventually found clusters of potentially biological-looking structures entombed by calcium carbonate minerals. Significant time was devoted to interrogate the morphology and chemistry of these structures to convince themselves that they were looking at probable microbial remains. 

Serpentinizing environments have gained a lot of attention as places where microbes can thrive from water-rock reactions, and scientists think these processes may be ubiquitous beyond Earth. Hydrogen released during serpentinization can be a source of chemical energy in the subsurface of Mars and in the icy ocean worlds like Europa and Enceladus in the outer solar system.

For Lima-Zaloumis and the team, they hope that their research will bring more attention to serpentinizing environments as places where fossil evidence of microbes can be found. 

“Redox gradients in serpentinzing systems are capable of generating amino acids and other organic materials associated with life, which makes this work highly relevant for missions to Mars and ocean worlds,” said Bose.

Lima-Zaloumis shared he is hopeful that future studies will uncover more examples of fossilized organisms in serpentinites around the world, which will help researchers develop a fuller understanding of how ubiquitous (or not) these preservation processes are, and how best to apply these lessons to similar rocks beyond Earth. 

Other contributing authors on this study are Anna Neubeck, Uppsala University, Department of Palaeobiology Geocentrum, Villavägen; Magnus Ivarsson, Swedish Museum of Natural History, Department of Palaeobiology; Rebecca Greenberger, Caltech Division of Geological and Planetary Sciences; Alexis S. Templeton, University of Colorado, Department of Geological Sciences; Andrew D. Czaja, University of Cincinnati, Department of Geology; Peter B. Kelemen, Columbia University, Lamont-Doherty Earth Observatory; and Tomas Edvinsson, Uppsala University, Department of Materials Science and Engineering.

Science paper:
Nature Communications Earth & Environment
See the science paper for instructive material with images.

See the full article here.

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The Arizona State University Tempe Campus

The Arizona State University is a public research university in the Phoenix metropolitan area. Founded in 1885 by the 13th Arizona Territorial Legislature, ASU is one of the largest public universities by enrollment in the U.S.

One of three universities governed by the Arizona Board of Regents, The Arizona State University is a member of the Universities Research Association and classified among “R1: Doctoral Universities – Very High Research Activity.” The Arizona State University has nearly 150,000 students attending classes, with more than 38,000 students attending online, and 90,000 undergraduates and more nearly 20,000 postgraduates across its five campuses and four regional learning centers throughout Arizona. The Arizona State University offers 350 degree options from its 17 colleges and more than 170 cross-discipline centers and institutes for undergraduates students, as well as more than 400 graduate degree and certificate programs. The Arizona State Sun Devils compete in 26 varsity-level sports in the NCAA Division I Pac-12 Conference and is home to over 1,100 registered student organizations.

The Arizona State University ‘s charter, approved by the board of regents in 2014, is based on the New American University model created by The Arizona State University President Michael M. Crow upon his appointment as the institution’s 16th president in 2002. It defines The Arizona State University as “a comprehensive public research university, measured not by whom it excludes, but rather by whom it includes and how they succeed; advancing research and discovery of public value; and assuming fundamental responsibility for the economic, social, cultural and overall health of the communities it serves.” The model is widely credited with boosting The Arizona State University ‘s acceptance rate and increasing class size.

The university’s faculty of more than 4,700 scholars has included 5 Nobel laureates, 6 Pulitzer Prize winners, 4 MacArthur Fellows, and 19 National Academy of Sciences members. Additionally, among the faculty are 180 Fulbright Program American Scholars, 72 National Endowment for the Humanities fellows, 38 American Council of Learned Societies fellows, 36 members of the Guggenheim Fellowship, 21 members of the American Academy of Arts and Sciences, 3 members of National Academy of Inventors, 9 National Academy of Engineering members and 3 National Academy of Medicine members. The National Academies has bestowed “highly prestigious” recognition on 227 Arizona State University faculty members.

The Arizona State University was established as the Territorial Normal School at Tempe on March 12, 1885, when the 13th Arizona Territorial Legislature passed an act to create a normal school to train teachers for the Arizona Territory. The campus consisted of a single, four-room schoolhouse on a 20-acre plot largely donated by Tempe residents George and Martha Wilson. Classes began with 33 students on February 8, 1886. The curriculum evolved over the years and the name was changed several times; the institution was also known as Tempe Normal School of Arizona (1889–1903), Tempe Normal School (1903–1925), Tempe State Teachers College (1925–1929), Arizona State Teachers College (1929–1945), Arizona State College (1945–1958) and, by a 2–1 margin of the state’s voters, The Arizona State University in 1958.

In 1923, the school stopped offering high school courses and added a high school diploma to the admissions requirements. In 1925, the school became the Tempe State Teachers College and offered four-year Bachelor of Education degrees as well as two-year teaching certificates. In 1929, the 9th Arizona State Legislature authorized Bachelor of Arts in Education degrees as well, and the school was renamed The Arizona State Teachers College. Under the 30-year tenure of president Arthur John Matthews (1900–1930), the school was given all-college student status. The first dormitories built in the state were constructed under his supervision in 1902. Of the 18 buildings constructed while Matthews was president, six are still in use. Matthews envisioned an “evergreen campus,” with many shrubs brought to the campus, and implemented the planting of 110 Mexican Fan Palms on what is now known as Palm Walk, a century-old landmark of the Tempe campus.

During the Great Depression, Ralph Waldo Swetman was hired to succeed President Matthews, coming to The Arizona State Teachers College in 1930 from The Humboldt State Teachers College where he had served as president. He served a three-year term, during which he focused on improving teacher-training programs. During his tenure, enrollment at the college doubled, topping the 1,000 mark for the first time. Matthews also conceived of a self-supported summer session at the school at The Arizona State Teachers College, a first for the school.


In 1933, Grady Gammage, then president of The Arizona State Teachers College at Flagstaff, became president of The Arizona State Teachers College at Tempe, beginning a tenure that would last for nearly 28 years, second only to Swetman’s 30 years at the college’s helm. Like President Arthur John Matthews before him, Gammage oversaw the construction of several buildings on the Tempe campus. He also guided the development of the university’s graduate programs; the first Master of Arts in Education was awarded in 1938, the first Doctor of Education degree in 1954 and 10 non-teaching master’s degrees were approved by the Arizona Board of Regents in 1956. During his presidency, the school’s name was changed to Arizona State College in 1945, and finally to The Arizona State University in 1958. At the time, two other names were considered: Tempe University and State University at Tempe. Among Gammage’s greatest achievements in Tempe was the Frank Lloyd Wright-designed construction of what is Grady Gammage Memorial Auditorium/ASU Gammage. One of the university’s hallmark buildings, Arizona State University Gammage was completed in 1964, five years after the president’s (and Wright’s) death.

Gammage was succeeded by Harold D. Richardson, who had served the school earlier in a variety of roles beginning in 1939, including director of graduate studies, college registrar, dean of instruction, dean of the College of Education and academic vice president. Although filling the role of acting president of the university for just nine months (Dec. 1959 to Sept. 1960), Richardson laid the groundwork for the future recruitment and appointment of well-credentialed research science faculty.

By the 1960s, under G. Homer Durham, the university’s 11th president, The Arizona State University began to expand its curriculum by establishing several new colleges and, in 1961, the Arizona Board of Regents authorized doctoral degree programs in six fields, including Doctor of Philosophy. By the end of his nine-year tenure, The Arizona State University had more than doubled enrollment, reporting 23,000 in 1969.

The next three presidents—Harry K. Newburn (1969–71), John W. Schwada (1971–81) and J. Russell Nelson (1981–89), including and Interim President Richard Peck (1989), led the university to increased academic stature, the establishment of The Arizona State University West campus in 1984 and its subsequent construction in 1986, a focus on computer-assisted learning and research, and rising enrollment.


Under the leadership of Lattie F. Coor, president from 1990 to 2002, The Arizona State University grew through the creation of the Polytechnic campus and extended education sites. Increased commitment to diversity, quality in undergraduate education, research, and economic development occurred over his 12-year tenure. Part of Coor’s legacy to the university was a successful fundraising campaign: through private donations, more than $500 million was invested in areas that would significantly impact the future of The Arizona State University. Among the campaign’s achievements were the naming and endowing of Barrett, The Honors College, and the Herberger Institute for Design and the Arts; the creation of many new endowed faculty positions; and hundreds of new scholarships and fellowships.

In 2002, Michael M. Crow became the university’s 16th president. At his inauguration, he outlined his vision for transforming The Arizona State University into a “New American University”—one that would be open and inclusive, and set a goal for the university to meet Association of American Universities criteria and to become a member. Crow initiated the idea of transforming The Arizona State University into “One university in many places”—a single institution comprising several campuses, sharing students, faculty, staff and accreditation. Subsequent reorganizations combined academic departments, consolidated colleges and schools, and reduced staff and administration as the university expanded its West and Polytechnic campuses. The Arizona State University’s Downtown Phoenix campus was also expanded, with several colleges and schools relocating there. The university established learning centers throughout the state, including The Arizona State University Colleges at Lake Havasu City and programs in Thatcher, Yuma, and Tucson. Students at these centers can choose from several Arizona State University degree and certificate programs.

During Crow’s tenure, and aided by hundreds of millions of dollars in donations, The Arizona State University began a years-long research facility capital building effort that led to the establishment of the Biodesign Institute at The Arizona State University, the Julie Ann Wrigley Global Institute of Sustainability, and several large interdisciplinary research buildings. Along with the research facilities, the university faculty was expanded, including the addition of five Nobel Laureates. Since 2002, the university’s research expenditures have tripled and more than 1.5 million square feet of space has been added to the university’s research facilities.

The economic downturn that began in 2008 took a particularly hard toll on Arizona, resulting in large cuts to The Arizona State University ‘s budget. In response to these cuts, The Arizona State University capped enrollment, closed some four dozen academic programs, combined academic departments, consolidated colleges and schools, and reduced university faculty, staff and administrators; however, with an economic recovery underway in 2011, the university continued its campaign to expand the West and Polytechnic Campuses, and establish a low-cost, teaching-focused extension campus in Lake Havasu City.

As of 2011, an article in Slate reported that, “the bottom line looks good,” noting that:

“Since Crow’s arrival, The Arizona State University’s research funding has almost tripled to nearly $350 million. Degree production has increased by 45 percent. And thanks to an ambitious aid program, enrollment of students from Arizona families below poverty is up 647 percent.”

In 2015, the Thunderbird School of Global Management became the fifth Arizona State University campus, as the Thunderbird School of Global Management at The Arizona State University. Partnerships for education and research with Mayo Clinic established collaborative degree programs in health care and law, and shared administrator positions, laboratories and classes at the Mayo Clinic Arizona campus.

The Beus Center for Law and Society, the new home of The Arizona State University’s Sandra Day O’Connor College of Law, opened in fall 2016 on the Downtown Phoenix campus, relocating faculty and students from the Tempe campus to the state capital.