The Volcanoes of Mars

By James R. Zimbelman, David A. Crown, Peter J. Mouginis-Mark and Tracy K. P. Gregg

The Volcanoes of Mars offers a clear, cohesive summary of Mars volcanology. It begins with an introduction to the geology and geography of the red planet and an overview of its volcanic history, and continues to discuss each distinct volcanic province, identifying the common and unique aspects of each region. Incorporating basic volcanological information and constraints on the regional geologic history derived from geologic mapping, the book also examines current constraints on the composition of the volcanic rocks as investigated by both orbiting spacecraft and rovers. In addition, it compares the features of Martian volcanoes to those seen on other volcanic bodies.

Concluding with prospects for new knowledge to be gained from future Mars missions, this book brings researchers in volcanology and the study of Mars up to date on the latest findings in the study of volcanoes on Mars, allowing the reader to compare and contrast Martian volcanoes to volcanoes studied on Earth and throughout the Solar System.

• Presents clearly organized text and figures that will quickly allow the reader to find specific aspects of Martian volcanism
• Includes definitions of geological and volcanological terms throughout to aid interdisciplinary understanding
• Summarizes key results for each volcanic region of Mars and provides copious citations to the research literature to facilitate further discovery
• Synthesizes the most current data from multiple spacecraft missions, including the Mars Reconnaissance Orbiter, as well as geochemical data from Martian meteorites
• Utilizes published geologic mapping results to highlight the detailed knowledge that exists for each region

• Language: English
• Publisher: Elsevier Science
• Release date: Dec 5, 2020
• ISBN: 9780128228777

James R. Zimbelman

James R. Zimbelman is Senior Geologist Emeritus at the Center for Earth and Planetary Studies in the National Air and Space Museum at the Smithsonian Institution, where he studies planetary geology including the geologic analysis of remote sensing data of Mars, geologic mapping of Mars and Venus, the study of long lava flows on the terrestrial planets, and field studies of volcanic, aeolian and pluvial features. In 2013 he received the Ronald Greeley Award for Distinguished Service, and in 2020 the G. K. Gilbert Award, both from the Planetary Geology Division (PGD) of the Geological Society of America (GSA). He is a Fellow of GSA, has served as Secretary of the American Geophysical Union’s Planetary Sciences section, an officer in PGD, and chair of the NASM Center for Earth and Planetary Studies.

Book preview

9780128228777_FC

The Volcanoes of Mars

First Edition

James R. Zimbelman

Senior Geologist Emeritus, Center for Earth and Planetary Studies, National Air and Space Museum, Smithsonian Institution, Washington, DC, United States

David A. Crown

Senior Scientist, Planetary Science Institute, Tucson, AZ, United States

Peter J. Mouginis-Mark

Emeritus Researcher, Hawai’i Institute Geophysics and Planetology, University of Hawai’i, Honolulu, HI, United States

Tracy K.P. Gregg

Associate Professor, Department of Geology, University of Buffalo, Buffalo, NY, United States

Table of Contents

Cover image

Title page

Copyright

About the authors

Preface

On the cover

1: Introduction: Welcome to Mars!

Abstract

1.1: Introduction

1.2: Learning about Mars

1.3: Geology

1.4: Volcanism

1.5: Plate tectonics

1.6: Samples from Mars

1.7: Chronology

1.8: Outline of the book

2: Areography

Abstract

2.1: Introduction

2.2: Physiography

2.3: Background: Martian volcanoes

2.4: Geologic mapping of Martian volcanoes

2.5: Conclusion

3: The Tharsis Province

Abstract

3.1: Introduction

3.2: Volcanic constructs

3.3: Unique features of Olympus Mons

3.4: Central plains of Tharsis

3.5: Explosive volcanism?

3.6: The role of glaciation

3.7: The uniqueness of Tharsis

3.8: Tharsis as the source for SNC meteorites

3.9: Summary and conclusions

4: The Elysium Province

Abstract

Acknowledgments

4.1: Introduction

4.2: Volcanic constructs

4.3: Volcanic flows

4.4: The role of ice

4.5: Recent activity

4.6: Unanswered questions and future studies

5: The Circum-Hellas Province

Abstract

5.1: Introduction

5.2: Spacecraft exploration

5.3: Central volcanoes

5.4: Post-Viking geologic investigations

5.5: Volcanic history

5.6: Future research

6: Syrtis Major and small highland volcanoes

Abstract

6.1: Introduction

6.2: Regional geography and geology

6.3: Tectonic and volcanic history

6.4: Composition of Syrtis Major deposits

6.5: Exploration of Jezero crater

6.6: Small highland volcanoes

6.7: Conclusions

7: Medusae Fossae Formation and the northern lowlands

Abstract

7.1: Introduction

7.2: Observations of MFF

7.3: Interpretations of MFF

7.4: Explosive eruptions on Mars

7.5: Recent studies of MFF

7.6: Apollinaris Mons

7.7: Volcanic explosions in the northern lowlands

7.8: Conclusions

8: Igneous composition

Abstract

8.1: Introduction

8.2: Why is composition important?

8.3: Composition at a distance (remote sensing)

8.4: Composition from the Martian surface (in situ)

8.5: Combining orbital and surface data

8.6: Martian meteorites

8.7: Synthesis

8.8: What does it all mean?

9: Lava worlds: Cosmic cousins

Abstract

9.1: Introduction

9.2: Earth

9.3: The Moon

9.4: Venus

9.5: Mercury

9.6: Io

9.7: Asteroids and silicate volcanism

9.8: Cryovolcanism

9.9: Summary

10: What's next?

Abstract

10.1: Introduction

10.2: InSight

10.3: Mars 2020 Perseverance rover (NASA)

10.4: ExoMars 2022 rover (ESA)

10.5: Other near-term Mars missions

10.6: Mars Sample Return (MSR)

10.7: Humans to Mars (… eventually …)

10.8: The allure of Mars

Appendix

USGS geologic maps of Mars including Martian volcanoes

Index

Copyright

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About the authors

James R. Zimbelman is a Senior Geologist Emeritus at the Center for Earth and Planetary Studies in the National Air and Space Museum at the Smithsonian Institution, where he studies planetary geology including the geologic analysis of remote sensing data of Mars, geologic mapping of Mars and Venus, the study of long lava flows on the terrestrial planets, and field studies of volcanic, aeolian, and pluvial features. In 2013 he received the Ronald Greeley Award for Distinguished Service, and in 2020 the G. K. Gilbert Award, both from the Planetary Geology Division (PGD) of the Geological Society of America (GSA). He is a fellow of GSA, has served as secretary of the American Geophysical Union's Planetary Sciences section, an officer in PGD, and chair of the NASM Center for Earth and Planetary Studies.

David A. Crown is a Senior Scientist at the Planetary Science Institute (Tucson, AZ), with professional interests in planetary geology, physical volcanology, remote sensing, and science education. His research studies focus on understanding the geologic histories of the rocky planetary bodies in the solar system and include geologic mapping investigations of the surfaces of Mars, Venus, Io, and Ceres, use of spacecraft and airborne remote sensing data for geologic analyses of planetary surface features, field investigations of volcanic deposits, and the development and application of models for geologic flows. He has published nine geologic maps of Mars to-date, eight of which examined the geology of the Hellas region. He has conducted field studies of volcanic terrains in the western continental US, Hawai'i, Mexico, and in the Central Andes of Bolivia.

Peter J. Mouginis-Mark is an Emeritus Researcher at the Hawai'i Institute of Geophysics and Planetology (HIGP), University of Hawai'i (UH). For more than 40 years, he has studied volcanoes in the solar system and on Earth. He has conducted fieldwork not only in Hawai'i but also such diverse places as the Galapagos Islands, Reunion Island, Chile, Java, Iceland, Nicaragua, and the Philippines. He has served as geology program manager at NASA Headquarters and the director of HIGP and associate dean for Research, College of Engineering, both at UH. He was principal investigator for an international 14-year NASA study to use satellites to study active volcanoes on Earth and has been a leader for 13 NASA week-long planetary volcanology field workshops in Hawai'i. Pete has published more than 125 peer-reviewed research papers, of which 35 have focused on Martian volcanism.

Tracy K.P. Gregg is an Associate Professor in the Department of Geology at the University of Buffalo in Buffalo, NY. Her primary research interest is lava flows, and she is not particular about where they are or their composition. She has done fieldwork on lava flows in Idaho, Peru, Iceland, and Hawai'i, as well as studied volcanic morphologies on Mars, the Moon, Venus, and Jupiter's moon Io. She has personally investigated lavas at the East Pacific Rise and the Galapagos Spreading Center, more than 2500 m below sea level, from the safety of the submersible Alvin. She supervised the NASA Planetary Geology and Geophysics Undergraduate Research Program (PGGURP) for 20 years and is now helping to run its sequel [Summer Undergraduate Program for Planetary Research (SUPPR)]. Tracy is a fellow of the Geological Society of America (GSA) and was awarded the Ronald Greeley Award for Distinguished Service from the GSA Planetary Geology Division.

Preface

James R. Zimbelmana,*; David A. Crownb; Peter J. Mouginis-Markc; Tracy K.P. Greggd, a Smithsonian Institution, Washington, DC, United States

b Planetary Science Institute, Tucson, AZ, United States

c University of Hawai'i, Honolulu, HI, United States

d University of Buffalo, Buffalo, NY, United States

⁎ Corresponding Author. [e-mail]

The title of this book may sound like a topic for science fiction, but perhaps even more remarkable is the realization that the information presented here is the result of decades of detailed scientific studies of the geology of Mars from multiple spacecraft missions. We are fortunate to be living when robotic spacecraft have provided humanity with its first knowledge of the incredible diversity within the solar system in general and of the beguiling Red Planet in particular. We are challenged to explain how a planet half the size of Earth produced several volcanoes that are many times larger than any volcano on Earth. This book serves as an introduction to the breadth and diversity of volcanism as it has been expressed throughout Martian history. We want the reader to realize that this effort represents only some of the reasons why the Martian volcanoes have intrigued, challenged, stumped, and bewitched all of us for decades—and continue to enthrall humanity.

The book is primarily intended for use by undergraduate-level students, but we have also striven to make the text accessible to the interested reader in the general public, as well as a useful review for planetary scientists at the graduate level and above. Descriptions are written primarily for a nonspecialist reader, but some chapters assume more of a background in geology than others. Terms are shown in bold where first introduced or described in each chapter. There is extensive citation of the published literature throughout so that anyone who is intrigued by a particular subject can seek greater detail from primary sources found in both scientific journals and books, as well as from reputable sources on the Internet. Many chapters highlight the importance of geologic mapping to document the sequence of generation and emplacement of the rocks and landforms visible from orbit on the Martian volcanoes; geologic mapping is an investigative tool that has been widely used by the authors. Most chapters are prefaced by an example of a geologic map for the area of interest. We hope that as one goes through the chapters, the reader will get a sense of the wonder and excitement stimulated by the impressive volcanoes that are widely distributed across Mars.

This book could not have happened without the efforts of several people who do not appear in the author lists for each chapter. Marisa LeFleur approached us to consider the topic for a possible book project with Elsevier, and Michael Lutz and Ruby Smith helped to bring the manuscript through the many stages involved in bringing it to a successful conclusion. We thank the colleagues who provided input to various versions of the chapters, especially Hap McSween (University of Tennessee) for his insightful comments on Chapter 8. We also offer our deep gratitude to Jake Bleacher (NASA) and Brent Garry (NASA Goddard) who were instrumental in the genesis of this book. Three of us benefited greatly from the knowledge and guidance provided by Ronald Greeley during graduate studies at Arizona State University. Interactions with friends and colleagues have continued to stimulate a desire to increase our understanding of the forces that produced the remarkable volcanoes of Mars. As is the case with any book-length project, we could not have completed the task without the support and forbearance of both our family and friends while we were often cloistered in our offices.

On the cover

The High Resolution Stereo Camera captured this impressive view of volcanic Mars (looking obliquely to the southeast) on June 29, 2014, during orbit 13,323 of the Mars Express orbiter. Olympus Mons, the tallest volcano on Mars, is at lower right. Three slightly smaller Tharsis Montes volcanoes (Ascraeus Mons, Pavonis Mons, Arsia Mons, left to right) are visible closer to the horizon. Two other volcanoes (Ulysses Patera and Biblis Patera, left to right) are in between the four larger volcanoes. The thin Martian atmosphere is visible above the curve of the limb of Mars (ESA/DLR/FU Berlin/Justin Cowart).

1: Introduction: Welcome to Mars!

James R. Zimbelmana,*; David A. Crownb; W. Brent Garryc; Jacob E. Bleacherc    a Smithsonian Institution, Washington, DC, United States

b Planetary Science Institute, Tucson, AZ, United States

c NASA Goddard Space Flight Center, Greenbelt, MD, United States

* Corresponding author. [e-mail]

Abstract

Mars has intrigued and puzzled humanity for centuries. Volcanism on Mars illustrates how the Red Planet releases internal heat. Martian volcanoes are very similar to, while also fascinatingly distinct from, the many volcanoes on Earth. Volcanoes on Mars do not appear to result from the movement of crustal plates, unlike almost all volcanoes on Earth. In spite of this difference, we still use the terminology developed over centuries of studying volcanoes on Earth to characterize the many volcanic constructs that are distributed among volcanic provinces spread across Mars. Thanks to hundreds of meteorites that originated on Mars, we know that Martian volcanic rocks are similar to basalts on Earth. This book will introduce the reader to the diversity and complexity of the volcanoes on Mars.

Keywords

Igneous; Magma; Lava flow; Pyroclastic; Mars meteorites; Chronology

1.1: Introduction

People have watched a red wandering object in the night sky for millennia, wondering what it could be. Its distinctive orange-red (ochre) color (Fig. 1.1) made many cultures associate this moving star with warfare, and Mars is named after the Roman god of war. Today, we know that all of these wandering stars are planets orbiting the Sun just as Earth does, but Mars continues to be the planet that most often captures our attention and our imagination (as in the well-known stories by H.G. Wells, E.R. Burroughs, and R. Bradbury or in countless science fiction movies since the 1930s). Increasingly sophisticated spacecraft have become humanity's robotic emissaries to the Red Planet, taking our fascination with Mars out of the realm of science fiction into that of science fact. These spacecraft data have revealed abundant evidence that Mars is home to some of the most dramatic and amazing volcanoes in our solar system, the subject of this book.

Fig. 1.1

Fig. 1.1 Pre-spacecraft Mars . Portion of a telescope-based map of Mars published shortly before Mariner 4 revealed the cratered nature of the Martian surface. Map section shown includes many linear dark features associated with Percival Lowell's canals, plus Nix Olympica (now Olympus Mons; see Fig. 1.2). U.S. Air Force (1965)/Lunar and Planetary Institute.

How did a planet half the size of the Earth produce enormous volcanic mountains like Olympus Mons (Fig. 1.2), something many times the size of the largest volcanoes on Earth? Why are the Martian volcanoes located where they are? Do volcanoes in close proximity have the same eruptive histories and were they active at the same time, or were there different eruption styles in the same region in different geologic epochs? Questions such as these are examples of the many issues currently being investigated under the broad umbrella represented by the term comparative planetology. Today, we have some understanding of all of the planets in the solar system, thanks to the many spacecraft missions launched from Earth during the last half century. These explorations have discovered that volcanism is a ubiquitous geologic process across the terrestrial (rocky) planets and even to an extreme on the bizarre moon of Jupiter named Io. In the outer solar system, water takes the place of molten rock, a process called cryovolcanism. However, among all of these volcanic worlds, the relatively diminutive planet Mars has some of the largest volcanoes to be seen anywhere. Through this book, we will take you, the reader, on a fantastic journey of exploration to the many volcanoes of Mars.

Fig. 1.2

Fig. 1.2 Olympus Mons volcano . Shaded relief renditions of Olympus Mons on Mars (NASA Mars Oribter Laser Altimeter data) and the Big Island of Hawai'i ( upper left ; NASA Shuttle Radar Topography Mission data). Both images are shown at the same scale.

The journey begins with a brief review of how scientists and engineers have steadily obtained increasingly detailed information about Mars. Subsequent chapters will focus on the volcanic history of the Red Planet by discussing several distinct volcanic provinces, emphasizing both familiar and unique aspects of each region. The goal is for this compilation of information to provide a current synthesis of our knowledge of Martian volcanoes and to allow the reader to compare and contrast Martian volcanoes with the many volcanoes that have been studied in great detail here on Earth, as well as to volcanoes now known throughout the solar system.

1.2: Learning about Mars

The ancients were keen observers of the night sky. Over 2500 years ago, Babylonian astronomers regularly recorded how Mars moved among the seemingly fixed stars, and Chinese astronomers documented that Mars occasionally moved in a retrograde direction (the reverse of its normal motion) for weeks at a time before returning to its more regular motion (Bakich, 2000, pp. 169–171). Exotic ideas were developed to explain this perplexing behavior, which both Jupiter and Saturn also exhibited, but to a lesser degree than that demonstrated by Mars. Careful measurements of Mars by Tycho Brahe allowed Johannes Kepler to devise his famous three laws of planetary motion in 1600, the first of which states that planets follow elliptical (noncircular) orbits with the sun at one focus of the ellipse, the first mathematical description of a planetary orbit.

Scientific investigation of Mars began in earnest following Galileo's 1610 publication that let the world know that the telescope was a wonderful new tool for exploring the heavens. Telescopes soon revealed the presence of lighter and darker regions on Mars, but perhaps even more important, Mars did not exhibit phases similar to those seen monthly for Earth's Moon, unlike what Galileo's telescope also revealed for Venus. These early telescopic observations provided observational support for Copernicus’ model of the sun-centered solar system, with Venus closer to the Sun and Mars further from the Sun than was the Earth. As telescopes became ever more powerful, Mars showed variations in its surface features that repeated during the nearly 2 Earth years it takes for Mars to make one revolution around the Sun. Eventually, bright polar caps were detected on the planet, including parts that remained year-round, while other polar deposits grew and shrank throughout the Martian year. In the 1780s Sir William Herschel (the astronomer who discovered the planet Uranus) used such observations to suggest that Mars experienced seasons similar to those of Earth (Bakich, 2000, p. 183). Occasionally the whole globe of Mars became a uniform ochre color with no surface detail discernable; this was eventually attributed to massive dust storms that at times obscured the entire surface for many weeks.

Telescopic observations of Mars are best obtained about every 26 Earth months, when Mars is at opposition (directly opposite from the Sun as viewed from the Earth), but the apparent size of Mars at these oppositions varies systematically because the orbit of Mars is more elliptical than the orbit of Earth. The 1877 opposition was a particularly good one, and Giovanni Schiaparelli made a detailed map of Mars that included numerous straight dark lines across the bright regions. His map was published in 1890 with the lines labeled canali (meaning a natural channel or groove in Italian), but this word was loosely translated into English as canals, which implied features constructed by intelligent beings (Bakich, 2000, p. 183). Percival Lowell expanded on the concept of Martian canals in his 1895 book titled Mars, championing the idea that Martians globally engineered the planet to bring water from the polar regions to parched equatorial deserts (Fig. 1.3). Until his death in 1916, Lowell used his personal observatory in Flagstaff, Arizona (which remains an active research center today), to make maps of the extensive Martian canal system, and he published more books to popularize his interpretation that advanced intelligent life existed on Mars. The canals remained unseen by most other telescopic observers, but Lowell was undeterred. The possibility of advanced life on Mars remained popular until the first spacecraft to fly past Mars (Mariner 4, in 1965) returned 22 images of a mostly cratered surface reminiscent of Earth's Moon.

Fig. 1.3

Fig. 1.3 Lowell Mars globe . Mars globe (5″ diameter) with hand-drawn observations recorded by Percival Lowell in 1901. Globe was on loan from Lowell Observatory while on display at the National Air and Space Museum.

Volcanoes entered the Mars story in 1971 when Mariner 9 became the first spacecraft to orbit another planet. The spacecraft arrived at Mars during the most intense global dust storm in decades, but commands from Earth kept it from starting its global mapping mission until the dust began to clear. As the dust pall gradually settled out of the thin Martian atmosphere, four dark spots appeared in Mariner images taken to monitor the progress of the dust storm (Fig. 1.4). With continued dust settling, the spots soon resolved into elevated regions each with complex craters at their summits. It did not take scientists long to deduce that tall mountains with craters at their summits were most likely volcanoes. Once the atmosphere fully cleared, Mariner 9 mapped the entire Martian surface at a spatial resolution far exceeding what was possible with the largest telescopes on Earth, giving humanity the first detailed look at the scope of the geology of Mars. This global mapping effort revealed that the four spots were the summits of the largest volcanoes then known, as well as finding many other volcanic centers scattered across the planet (Mutch et al., 1976, pp. 36–39). Subsequent spacecraft orbiting and landing on Mars have provided increasingly detailed information about the Martian surface; this incredible wealth of data forms the basis for much of what is described in this book.

Fig. 1.4

Fig. 1.4 Mars' volcanoes revealed . Four dark spots (arrowed) were the first surface features seen in Mariner 9 images as the global dust storm of 1971 began to dissipate. The spots are the summits of four enormous volcanoes. At upper left is Olympus Mons (see Fig. 1.2); the three aligned dark spots are the Tharsis Montes. Extreme contrast stretching of these images caused the white echoes above and below each dark spot. Subtle dust cloud structures are evident throughout this image mosaic. NASA https://www.hq.nasa.gov/office/pao/History/SP-4212/ch9-4.html.

1.3: Geology

Interest in volcanoes and volcanism has a long history because many cultures wanted a way to explain why rivers of molten rock occasionally appeared from the Earth (Macdonald, 1972, pp. 26–41). One of the better known legends involves the Hawai'ian goddess of fire, Pele, who traveled from island to island (starting at Ni’ihau and moving southeast), eventually settling into the Halemaumau crater at the top of Kilauea volcano on the Big Island of Hawai'i (Beckwith, 1970; Cashman, 2004; Westervelt, 1916; Roberts, 2018). The direction of Pele's island migration is consistent with modern dating of volcanic rocks on the different islands; today, we explain this observation through the motion of Earth's rocky lithosphere above a deep-seated hot spot (see Section 1.7). However, before delving into modern concepts of volcanism, we should first consider several different types of rocks that are important to understanding the story behind volcanoes.

Geology is the science of the Earth, a relative newcomer to general sciences like physics, chemistry, and biology. For a long period of time, the collection of rocks was considered to fall within the realm of the hobbyist. In 1669 Nicolas Steno formulated the principle of superposition, which stated that rocks were emplaced in a temporal sequence with the older rocks beneath the younger ones (Press and Siever, 1974, p. 46). James Hutton, and later Charles Lyell, used the observed sequence of emplacement inferred from observations of which rocks lie on top of other rocks to deduce that geologic events occurred uniformly through time, which Lyell publicized as the principle of uniformitarianism (Press and Siever, 1974, pp. 61–62). This relationship became inadequate when it was recognized that some layered rocks, assumed to have originally formed in a horizontal orientation, were today tilted to different degrees, even to the point that some rocks were turned completely upside down.

When fossils were recognized to be remnants of past life preserved in the rocks, they became a crucial tool for defining stratigraphic sequences of rocks. Fossil-bearing strata are a subset of the more general sedimentary rock type. Sediments (fine particles) are deposited after settling out of either water or air, both mediums that can transport sediments long distances from their sources. Sedimentary rocks cover about 75% of the surface of the continents on the Earth (Hamblin and Christiansen, 1998, p. 106), so they are likely the rocks that most people think of first (when they think about rocks at all, a situation that we hope will be much encouraged by reading this book). The Grand Canyon (Arizona) is one of the best-known exposures of sedimentary rocks on Earth, where the upper 800 m of the canyon exposes a stratigraphic sequence representing more than 300 million years of Earth's history and the lower part of the canyon extends time back nearly 2 billion years, although many of those lower rocks are not sedimentary rocks.

Two important systems affect the Earth to deposit or change the rocks near its surface: the hydrologic system (a complex cycle through which water moves from the oceans to the atmosphere to the land and back to the oceans) and the tectonic system (the movement of solid rock near the Earth's surface) (Hamblin and Christiansen, 1998, pp. 32–42). Sedimentary rocks result from several different mechanisms working within the hydrologic system, and the tilting, folding, and faulting of sedimentary strata are the result of forces acting within the tectonic system. Some tectonic forces can bury rocks to various depths within the crust where increased heat and pressure, along with changes in the composition of fluids that may move through those rocks, alter the minerals in the original rock to generate metamorphic rocks. The third major rock type, igneous, forms from magma (a molten mixture of liquid rock material, gas, and solid crystals); if