Pit Craters Throughout the Solar System
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Hawaii Volcanoes National Park Geologic Resources Inventory Report
National Park Service U.S. Department of the Interior Natural Resource Program Center Hawai‘i Volcanoes National Park Geologic Resources Inventory Report Natural Resource Report NPS/NRPC/GRD/NRR—2009/163 THIS PAGE: Geologists have lloongng been monimonittoorriing the volcanoes of Hawai‘i Volcanoes National Park. Here lalava cascades durduriingng the 1969-1971 Mauna Ulu eruption of Kīlauea VolVolcano. NotNotee the Mauna Ulu fountountaiain in the background. U.S. Geologiogicalcal SurSurvveyey PhotPhotoo by J. B. Judd (12/30/1969). ON THE COVER: ContContiinuouslnuouslyy eruptuptiingng since 1983, Kīllaueaauea Volcano contcontiinues to shapshapee Hawai‘Hawai‘i VoVollccanoes NatiNationalonal ParkPark.. Photo courtesy Lisa Venture/UniversiUniversitty of Cincinnati. Hawai‘i Volcanoes National Park Geologic Resources Inventory Report Natural Resource Report NPS/NRPC/GRD/NRR—2009/163 Geologic Resources Division Natural Resource Program Center P.O. Box 25287 Denver, Colorado 80225 December 2009 U.S. Department of the Interior National Park Service Natural Resource Program Center Denver, Colorado The National Park Service, Natural Resource Program Center publishes a range of reports that address natural resource topics of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Report Series is used to disseminate high-priority, current natural resource management information with managerial application. The series targets a general, diverse audience, and may contain NPS policy considerations or address sensitive issues of management applicability. All manuscripts in the series receive the appropriate level of peer review to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner. -
Poroelastic Responses of Confined Aquifers to Subsurface Strain And
Solid Earth, 6, 1207–1229, 2015 www.solid-earth.net/6/1207/2015/ doi:10.5194/se-6-1207-2015 © Author(s) 2015. CC Attribution 3.0 License. Poroelastic responses of confined aquifers to subsurface strain and their use for volcano monitoring K. Strehlow, J. H. Gottsmann, and A. C. Rust School of Earth Sciences, University of Bristol, Wills Memorial Building, Bristol BS8 1RJ, UK Correspondence to: K. Strehlow ([email protected]) Received: 11 May 2015 – Published in Solid Earth Discuss.: 9 June 2015 Revised: 18 September 2015 – Accepted: 21 October 2015 – Published: 10 November 2015 Abstract. Well water level changes associated with mag- aquifer and are commonly neglected in analytical models. matic unrest can be interpreted as a result of pore pressure These findings highlight the need for numerical models for changes in the aquifer due to crustal deformation, and so the interpretation of observed well level signals. However, could provide constraints on the subsurface processes caus- simulated water table changes do indeed mirror volumetric ing this strain. We use finite element analysis to demonstrate strain, and wells are therefore a valuable addition to monitor- the response of aquifers to volumetric strain induced by pres- ing systems that could provide important insights into pre- surized magma reservoirs. Two different aquifers are invoked eruptive dynamics. – an unconsolidated pyroclastic deposit and a vesicular lava flow – and embedded in an impermeable crust, overlying a magma chamber. The time-dependent, fully coupled models simulate crustal deformation accompanying chamber pres- 1 Introduction surization and the resulting hydraulic head changes as well as flow through the porous aquifer, i.e. -
Discrete Element Modelling of Pit Crater Formation on Mars
geosciences Article Discrete Element Modelling of Pit Crater Formation on Mars Stuart Hardy 1,2 1 ICREA (Institució Catalana de Recerca i Estudis Avançats), Passeig Lluís Companys 23, 08010 Barcelona, Spain; [email protected]; Tel.: +34-934-02-13-76 2 Departament de Dinàmica de la Terra i de l’Oceà, Facultat de Ciències de la Terra, Universitat de Barcelona, C/Martí i Franqués s/n, 08028 Barcelona, Spain Abstract: Pit craters are now recognised as being an important part of the surface morphology and structure of many planetary bodies, and are particularly remarkable on Mars. They are thought to arise from the drainage or collapse of a relatively weak surficial material into an open (or widening) void in a much stronger material below. These craters have a very distinctive expression, often presenting funnel-, cone-, or bowl-shaped geometries. Analogue models of pit crater formation produce pits that typically have steep, nearly conical cross sections, but only show the surface expression of their initiation and evolution. Numerical modelling studies of pit crater formation are limited and have produced some interesting, but nonetheless puzzling, results. Presented here is a high-resolution, 2D discrete element model of weak cover (regolith) collapse into either a static or a widening underlying void. Frictional and frictional-cohesive discrete elements are used to represent a range of probable cover rheologies. Under Martian gravitational conditions, frictional-cohesive and frictional materials both produce cone- and bowl-shaped pit craters. For a given cover thickness, the specific crater shape depends on the amount of underlying void space created for drainage. -
Depth of Magma Chamber Determined by Experimental Petrologic Methods
DEPTH OF MAGMA CHAMBER DETERMINED BY EXPERIMENTAL PETROLOGIC METHODS Akihiko Tomiya Geological Survey of Japan, 1-1-3, Higashi, Tsukuba, Ibaraki, Japan Keywords: magma chamber, experimental petrology, Usu magma and, therefore, the composition of the residual melt, volcano, deep-seated geothermal resource that is, the evolved magma. ABSTRACT Thermodynamic conditions of a magma chamber can be estimated using petrographic information (e.g., compositions Depth of magma chamber (or young intrusive body) is one of and modal fractions of phenocrysts and groundmass) from a the most important parameters that determine the thermal representative rock erupted from the chamber. In order to structure and the circulation pattern of fluid around a estimate the pressure of magma chamber, the following geothermal area. The depth is also important when we methods are generally used; (1) geobarometer, (2) water recognize the magma chamber as a deep-seated geothermal content, and (3) melting experiment. One of the examples of resource itself. Here, we introduce an experimental petrologic the first method is an amphibole geobarometer (e.g., method for determining the depth of magma chamber. There Hammarstrom and Zen, 1986) where pressure is estimated are several methods in order to determine the depth (pressure) from the aluminum content of the amphibole crystallized from of a magma chamber. Among them, a melting experiment for the magma. This method, however, is difficult to apply to the rock erupted from the magma chamber is the most reliable natural magma because the geobarometer should be applied method. The method consists of the following procedure: (1) only when the mineral assemblage of the magma is the same as Select a sample (volcanic rock) which is representative of that of experimental products for which the geobarometer was magma in the chamber; (2) Give a petrographic description of calibrated. -
150 Geologic Facts About California
California Geological Survey - 150th Anniversary 150 Geologic Facts about California California’s geology is varied and complex. The high mountains and broad valleys we see today were created over long periods of time by geologic processes such as fault movement, volcanism, sea level change, erosion and sedimentation. Below are 150 facts about the geology of California and the California Geological Survey (CGS). General Geology and Landforms 1 California has more than 800 different geologic units that provide a variety of rock types, mineral resources, geologic structures and spectacular scenery. 2 Both the highest and lowest elevations in the 48 contiguous states are in California, only 80 miles apart. The tallest mountain peak is Mt. Whitney at 14,496 feet; the lowest elevation in California and North America is in Death Valley at 282 feet below sea level. 3 California’s state mineral is gold. The Gold Rush of 1849 caused an influx of settlers and led to California becoming the 31st state in 1850. 4 California’s state rock is serpentine. It is apple-green to black in color and is often mottled with light and dark colors, similar to a snake. It is a metamorphic rock typically derived from iron- and magnesium-rich igneous rocks from the Earth’s mantle (the layer below the Earth’s crust). It is sometimes associated with fault zones and often has a greasy or silky luster and a soapy feel. 5 California’s state fossil is the saber-toothed cat. In California, the most abundant fossils of the saber-toothed cat are found at the La Brea Tar Pits in Los Angeles. -
Diamond Craters Oregon's Geologic
Text by Ellen M. Benedict, 1985 Features at stops correspond to points on a clock ago, a huge mass of hot gases, volcanic ashes, bits face. Imagine that you are standing in the middle of a of pumice and other pyroclastics (fire-broken rock) Travel And Hiking Hints clock face. Twelve o’clock is the road in front of you violently erupted. The blast – greater than the May and 6 o’clock the road behind. If you always align the 18, 1980, eruption of Mt. St. Helens – deposited a Diamond Craters is located in the high desert country clock face with the road, you should be able to locate layer of pyroclastics 30 to 130 feet thick over an area about 55 miles southeast of Burns, Oregon. It’s an the features. almost 7,000 square miles! isolated place and some precautions should be taken . when traveling in the area. Start Tour. Mileage begins halfway Pyroclastics are between milepost 40 and 41 on State normal behavior Diamond Craters has no tourist facilities. The nearest Highway 205 at the junction to Diamond. for magmas place where gasoline is sold is at Frenchglen. Turn left. (subsurface That’s the opinion held by scores of molten rocks) Keep your scientists and educators who have visited Diamond, Oregon, a small ranching community, was of rhyolitic (a vehicle on named in 1874 for Mace McCoy’s Diamond brand. volcanic material and studied the area. It has the “best and hard-packed The nearby craters soon became known as Diamond related to granite) most diverse basaltic volcanic features in the road surfaces Craters. -
Discovery of a Hydrothermal Fissure in the Danakil Depression
EPSC Abstracts Vol. 12, EPSC2018-381-1, 2018 European Planetary Science Congress 2018 EEuropeaPn PlanetarSy Science CCongress c Author(s) 2018 Discovery of a hydrothermal fissure in the Danakil depression Daniel Mège (1), Ernst Hauber (2), Mieke De Craen (3), Hugo Moors (3) and Christian Minet (2) (1) Space Research Centre, Polish Academy of Sciences, Poland ([email protected]), (2) DLR, Germany ([email protected], [email protected], (3) Belgian Nuclear Research Centre, Belgium ([email protected], [email protected]) Abstract Oily Lake and Gaet’Ale). It is manifested by (1) salt polygon geometry directly influenced by the underlying Volcanic rift zones are among the most emblematic fracture; (2) bubbling pools; (3) dead pools; (4) shallow analogue features on Earth and Mars [1-2], with expected sinkholes; (4) a variety of other micromorphologies differences mainly resulting from the different value of a related to free or pressurised upflow of gas and fluids; single parameter, gravity [3]. Beyond the understanding and (5) rare evidence of fumarolic activity. In this context, of the geology, rift zones provide appropriate the Yellow Lake appears as a possible salt karst feature hydrothermal environments for the development of [10] the location and growth of which is controlled by micro-organisms in extreme conditions which depend at relay zone deformation between the fissure segments. first order on endogenic processes, and weakly on the planetary climate conditions. The Europlanet 2018 3. Hydrothermal fluids Danakil field campaign enabled identifying a previously The physico-chemistry of fluids and minerals from two unreported 4.5 km long hydrothermal fissure on the Lake small pools located along the Yellow Lake Fissure, as Asale salt flats, the Erta Ale - Dallol segment of the well as the Yellow Lake, have been analysed (Table 1). -
Fs20193026.Pdf
Prepared in collaboration with U.S. Forest Service, Bureau of Land Management, U.S. Environmental Protection Agency, Colorado Division of Reclamation Mining and Safety, Colorado Department of Public Health and Environment, and Animas River Stakeholders Group Geological and Geophysical Data for a Three-Dimensional View— Inside the San Juan and Silverton Calderas, Southern Rocky Mountains Volcanic Field, Silverton, Colorado This study integrates geological and geophysical data important for developing a three-dimensional (3D) model of the San Juan-Silverton caldera complex. The project aims to • apply state-of-the-art geophysical data processing techniques to legacy data; • map subsurface lithologies, faults, vein structures, and surficial deposits that may be groundwater flow paths; • better understand geophysical response of mineral systems at depth; and • provide geological and geophysical frameworks that will inform mining reclamation decisions and mineral resource assessments. Introduction shallow properties important for understanding surface water and groundwater quality issues and will also improve knowl- The San Juan-Silverton caldera complex located near edge of deep geological structures that may have been conduits Silverton, Colorado, in the Southern Rocky Mountains volcanic for hydrothermal fluids that formed mineral deposits (fig. 1). field is an ideal natural laboratory for furthering the under- The study has general applications to mineral resource assess- standing of shallow-to-deep volcanic-related mineral systems. ments -
State of Stress During Onset and Evolution of Caldera Collapse
Originally published as: Holohan, E., Schöpfer, M. P. J., Walsh, J. J. (2015): Stress evolution during caldera collapse. - Earth and Planetary Science Letters, 421, p. 139-151. DOI: http://doi.org/10.1016/j.epsl.2015.03.003 1 Stress evolution during caldera collapse 2 E.P. Holohan(1,2), M.P.J. Schöpfer(1,3), & J.J. Walsh(1) 3 (1) GFZ Potsdam, Section 2.1 – Physics of Earthquakes and Volcanoes, Telegrafenberg, Potsdam 14473, Germany. 4 (2) Fault Analysis Group, UCD School of Geological Sciences, Dublin 4, Ireland. 5 (3) Department for Geodynamics and Sedimentology, University of Vienna, Althanstrasse 14, Vienna, Austria. 6 Email: [email protected] 7 8 Abstract 9 The dynamics of caldera collapse are subject of long-running debate. Particular uncertainties 10 concern how stresses around a magma reservoir relate to fracturing as the reservoir roof collapses, 11 and how roof collapse in turn impacts upon the reservoir. We used two-dimensional Distinct 12 Element Method models to characterise the evolution of stress around a depleting sub-surface 13 magma body during gravity-driven collapse of its roof. These models illustrate how principal stress 14 directions rotate during progressive deformation so that roof fracturing transitions from initial 15 reverse faulting to later normal faulting. They also reveal four end-member stress paths to fracture, 16 each corresponding to a particular location within the roof. Analysis of these paths indicates that 17 fractures associated with ultimate roof failure initiate in compression (i.e. as shear fractures). We 18 also report on how mechanical and geometric conditions in the roof affect pre-failure unloading and 19 post-failure reloading of the reservoir. -
USGS Professional Paper 1350, Vol. 2 of 2
VOLCANISM IN HAWAII Chapter 59 THE ROLE OF LAVA TUBES IN HAWAIIAN VOLCANOES By Ronald Greeley I ABSTRACT set on the initiation and evolution of lava tubes and their associated Lava tubes develop from eruptions that typically involve: flows. (1) moderate rates of effusion, (2) durations greater than one or Numerous studies of lava tubes have been made in areas two days, and (3) effusion of fluid lava (for example, pahoehoe) outside Hawaii, including Mount Elna (Guest and others, 1980), that has not been greatly degassed. Although some fountain-fed Mount St. Helens (Greeley and Hyde, 1972), and New Mexico lava and aa flows can fonn lava tubes, such occurrences are rare (Hatheway and Herring, 1970). From these studies and those in in Hawaii. Lava tubes feed flows: (1) directly from the vent (acting as extensions of the conduit), (2) from various holding Hawaii, lava tubes clearly reflect a particular style of volcanism and reservoirs (for example, lava ponds, lava lakes, filled pit cra are the primary means for the spread of some types of lava flows. ters), and (3) from flows on the flanks of volcanoes. Historical flows of greatest length in Hawaii were emplaced primarily via lava tubes, and many subaqueous flows involve lava tubes. 166'00' 166'00' Sustained flow of lava in tubes appears capable of erosion into preflow terrain. Photogeological analyses suggest that at least 30 percent of the flows (by area) on Mauna Loa, 58 percent of the flows on Kilauea, and 18 percentof the flows on Mount Etna were at least partly emplaced via tubes. -
Candidate Cave Entrances on Mars
G.E. Cushing – Candidate cave entrances on Mars. Journal of Cave and Karst Studies, v. 74, no. 1, p. 33–47. DOI: 10.4311/ 2010EX0167R CANDIDATE CAVE ENTRANCES ON MARS GLEN E. CUSHING U.S. Geological Survey, Astrogeology Science Center, 2255 N. Gemini Dr., Flagstaff, AZ 86001, USA, [email protected] Abstract: This paper presents newly discovered candidate cave entrances into Martian near-surface lava tubes, volcano-tectonic fracture systems, and pit craters and describes their characteristics and exploration possibilities. These candidates are all collapse features that occur either intermittently along laterally continuous trench-like depressions or in the floors of sheer-walled atypical pit craters. As viewed from orbit, locations of most candidates are visibly consistent with known terrestrial features such as tube-fed lava flows, volcano-tectonic fractures, and pit craters, each of which forms by mechanisms that can produce caves. Although we cannot determine subsurface extents of the Martian features discussed here, some may continue unimpeded for many kilometers if terrestrial examples are indeed analogous. The features presented here were identified in images acquired by the Mars Odyssey’s Thermal Emission Imaging System visible- wavelength camera, and by the Mars Reconnaissance Orbiter’s Context Camera. Select candidates have since been targeted by the High-Resolution Imaging Science Experi- ment. Martian caves are promising potential sites for future human habitation and astrobiology investigations; understanding their characteristics is critical for long-term mission planning and for developing the necessary exploration technologies. INTRODUCTION cosmic rays (e.g., Mazur et al., 1978; De Angeles et al., 2002; Boston et al., 2004; Cushing et al., 2007). -
Tuesday, May 4, 2021 1. Call to Order 2:30 Pm Leiopapa a Kamehameha Building Office
HA WAI'I BOARDON GEOGRAPHIC NAMES (HBGN) Tuesday, May 4, 2021 2:30 p.m. Leiopapa A Kamehameha Building Officeof Planning, 6th Floor Conference Room 235 S. Beretania Street Honolulu, Hawai'i 96813 Zoom Meeting information: https://bit.ly/hbgn-20210504 Meeting ID: 932 3302 1740 Passcode: 581819 1. Call to Order 2. Review ofMeeting Minutes forApril 6, 2021 3. Public Comments 4. Announcements 5. Status ofbills and resolutions in the Legislature 6. Discussion and Action on Permitted Interaction Group for Lo'ihi / Kama'ehu 7. Review selected place names on the island ofHawai'i (Camara) 8. Adjournment This meeting of the Hawai'i Board on Geographic Names (HBGN) will be available forlive viewing via Zoom. Zoom Meeting information: https://bit.ly/hbgn-20210504 or https://zoom.us/j/93233021740?pwd=Ui9LbmxwMERYRkhDWDR WUHZaeHFRdz09 Meeting ID: 932 3302 1740 Passcode: 581819 MINUTES DRAFT FOR THE MEETING OF THE HAWAI‘I BOARD ON GEOGRAPHIC NAMES DATE: April 6, 2021 TIME: 2:30 p.m. PLACE: Leiopapa A Kamehameha Building Office of Planning, 6th Floor Library 235 S. Beretania Street Honolulu, Hawai‘i 96813 AGENDA ITEM 1: Call to Order Mr. Marzan called the meeting to order at 2:36 p.m. The following were in attendance: MEMBERS: Marques Marzan (Bishop Museum) Arthur Buto for Mary Alice Evans (Office of Planning) Meyer Cummins (Land Survey Division) Holly McEldowney (Department of Land and Natural Resources) left early at 3:20pm Niniau Kawaihae (Department of Hawaiian Home Lands) Kapā Oliveira (University of Hawaiʻi at Mānoa) Brad Kaʻaleleo Wong (Office of Hawaiian Affairs) ABSENT: None GUESTS: Jennifer Runyon (USGS) Lāmaku Mikahala Roy Melia Lane-Kamahele Regina Hilo Bobby Camara Renee Pualani Louis Catherine Sullivan AGENDA ITEM 2: Review of Meeting Minutes for March 2, 2021 Lamakū Roy asked for her attendance to be recognized and that she is here to comment on the minutes from the March meeting.