ABSTRACT KLING, CORBIN LYLE. Pit Craters throughout the Solar System. (Under the direction of Dr. Paul K. Byrne). Pit craters are common features found on planetary bodies in the Solar System. Pit craters are circular to elliptical in plan view shape, and extraterrestrial examples usually have inverted conical shapes. Typically, pit craters are found in groups that are often aligned in chains, and often parallel to bounding normal faults. The frequency with which pit craters and normal faults are seen together has led to dilational faulting emerging as a leading mechanism for how pit craters form. Other possibilities for pit crater formation include lava tube collapse and phreatomagmatic eruptions above a dike tip. The occurrence of these features on many different worlds, from Earth to Mars to Venus makes understanding the factors that govern their formation important. But efforts to decipher how pits on other planetary surfaces form is often limited by image or topographic resolution of the available data. On Earth, we can investigate these landforms in the field and examine them in situ, allowing for detailed interpretations of how pits form and develop. This dissertation has three science chapters that look at pit crater assemblages in different geological environments, specifically on Earth and Mars, with additional data taken from the literature of pits on other planetary bodies. Together, these chapters offer new insight into the mechanisms of formation, morphological styles, and development of this abundant planetary landform type. Chapter 2 is a focused study on the contribution of pit craters to the complex topography at Noctis Labyrinthus, Mars, a large physiographic province east of the volcanic Tharsis rise and west of the Valles Marineris canyon system. The observations made at Noctis Labyrinthus lead to the interpretation that volatiles played a substantial role in the structural evolution of this region of Mars. Chapter 3 analyzes pit craters at several locations across the Solar System, underpinned by fieldwork at two sites on Earth: Craters of the Moon National Monument and Preserve in Idaho and Hawaii Volcanoes National Park on the big island of Hawai'i. The fieldwork in Idaho and Hawai'i provided a useful basis for understanding how pit craters can form from multiple different processes, either tectonic or volcanic, and evolve to similar morphologies. Chapter 4 focuses on a single set of pits within The Grabens region of Canyonlands National Park in Utah. Of the four sites studied in Chapter 4, three (Sites 1, 3, and 4) are situated along fractures (either seen in the field or interpreted from field or topographic data), implying that the formation of these pits at least has been heavily influenced by the tectonics in the region. Additionally, numerous features attributed to surficial water flow were noted near sinkholes in Sites 2, 3, Site 4, and which I interpret as secondary erosional features further contributing to the morphology of these features. This work shows that pits on Earth are much smaller than their extraterrestrial counterparts and that they can develop because of multiple processes. The resultant pit shape appears at least in part correlated with those formation mechanisms. Pits with cylindrical shapes are found in basaltic flows, which probably indicates that the basaltic flows in the walls are strong enough to maintain vertical or near- vertical walls for extended periods. Yet pits on other planetary bodies are often shaped like inverted cones, and this finding can mean one of two things: 1) that either the pits originally formed in unconsolidated material and always assumed an inverted conical shape; and/or 2) that the pits initially formed as cylinders, either in competent material or less cohesive material and subsequent, secondary processes then led the pit walls to taking on an inverted conical shape. © Copyright 2020 by Corbin Lyle Kling All Rights Reserved Pit Craters throughout the Solar System by Corbin Lyle Kling A dissertation submitted to the Graduate Faculty of North Carolina State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy Marine, Earth, and Atmospheric Sciences Raleigh, North Carolina 2020 APPROVED BY: _______________________________ _______________________________ Paul Kevin Byrne Danielle Wyrick Committee Chair External Member _______________________________ _______________________________ Karl W. Wegmann Helena Mitasova _______________________________ Delwayne Bohnenstiehl ii DEDICATION To Alli, Mom, Dad, and Tyler. I would not be here today without all of your love and support. “So, it’s kind of like the quest for the holy grail. Well, you know, who gives a shit what the holy grail is. It’s the quest is what’s important.” –Yvon Chouinard iii BIOGRAPHY Corbin received his Bachelors of Science in Geology from the University of Georgia (UGA) in 2014. He continued into the Masters of Science program at UGA, and finished in 2016. He joined the Marine, Earth, and Atmospheric Sciences (MEAS) Department at NC State for his Ph.D. in the fall of 2016. During his time at NC State, Corbin has participated in many extracurricular events in the department in addition to his Ph.D. coursework and research, including a year as the President of the Graduate Student Association MEAS Chapter, the NC State Graduate School Writing Certificate, and the Preparing the Professoriate Program. Following the completion of his Ph.D., Corbin will be joining the Center for Earth and Planetary Studies at the National Air and Space Museum as a Smithsonian Postdoctoral Fellow at the conclusion of his Ph.D. iv ACKNOWLEDGMENTS First I would like to acknowledge the funding sources that supported my Ph.D. throughout my time at NC State. The NC State Graduate School Graduate Student Support Plan provided funding the first year of my Ph.D. The NASA Earth and Space Science Fellowship provided funding for the final three years of my Ph.D. work (grant #: 80NSSC17K0491). Two Geological Society of America Graduate Student Grants provided funding for the Craters of the Moon National Monument and Canyonlands National Park fieldwork. Fieldwork was completed with the assistance of multiple colleagues. Field photos of Hawaiian pit craters and locations of previously unpublished pit craters around Kilauea were generously provided by D. Wyrick prior to my first visit to those sites. I was able to visit all the pit sites in Hawaii Volcanoes National Park for the first time due to the generosity of Dr. Bob Craddock from the Smithsonian, who provided housing accommodations near the park in April 2018. Allison Vo, Julian Chesnutt, and Dr. Paul Byrne provided field assistance in Craters of the Moon National Monument and Preserve in the Summer of 2018. Zach Williams provided field assistance during the Canyonlands National Park fieldwork in October 2019. Finally, I would like to thank my committee for their unwavering support throughout my time at NC State. v TABLE OF CONTENTS LIST OF TABLES ...................................................................................................................... viii LIST OF FIGURES ...................................................................................................................... ix Chapter 1: Introduction 1.1. Pit Craters.................................................................................................................... 1 1.2. Science Chapters ......................................................................................................... 2 1.3. Key Findings ............................................................................................................... 5 Chapter 2: Tectonic Deformation and Volatile Loss in the Formation of Noctis Labyrinthus, Mars ..................................................................................................................... 10 Plain Language Summary ............................................................................................................ 11 Abstract ........................................................................................................................................ 11 1. Introduction .............................................................................................................................. 12 1.1. Noctis Labyrinthus .................................................................................................... 12 1.2. Faulting within Noctis Labyrinthus .......................................................................... 15 1.3. Pit Craters.................................................................................................................. 17 2. Methods.................................................................................................................................... 19 2.1. Datasets ..................................................................................................................... 19 2.2. Mapping .................................................................................................................... 20 2.3. Topographic Analysis ............................................................................................... 21 2.3.1. Fault Displacement Profile Analysis ......................................................... 21 2.3.2. Pit Crater and Trough Analysis.................................................................. 22 3. Results .....................................................................................................................................