Mauna Ulu Research Articles

Interpretation of the relations between massive, pillowed and brecciated facies in an archean submarine andesite volcano — amulet andesite, rouyn-noranda, Canada

The Amulet andesite formation in the Archean terrain of Rouyn-Noranda, P.Q., consists of 19 flows, distinguished by variations in phenocryst content and vesicularity and by the presence of concentric contraction fractures. Detailed mapping of flows revealed the presence of three main facies: (1) massive facies; (2) pillowed facies; and (3) foreset-bedded (brecciated) facies. The massive facies consists of > 50% massive lava overlain by pillow lava and/or pillow breccia. The pillowed facies consists of > 50% pillows. In some flows, the pillowed facies contains a thin sheet of massive lava at the base of the flow (facies 2a). Generally, massive lava fills braided channels 10–50 m wide (facies 2b). Facies 2c consists of pillows and large, irregular, megapillows. Determination of the flow direction shows that facies 1 is proximal, facies 2 distal. The foreset-bedded facies 3 consists of alternating thin (1–2 m) lobes of massive lava, pillow lava and broken-pillow breccia. It makes up flows 16–19 at the top of the sequence. Flow M, a unit entirely composed of massive lava, is ponded against flows 9 and 10. We interpret the growth of the Amulet andesite volcano in the light of new work on ocean-floor basalt and on the 1969–1973 Mauna Ulu eruption. The feeding fissure was located in the area of massive facies. At the beginning of eruptions lava spread laterally as a sheet-flood flow (massive base of facies 2a) but rapidly became channelized. The pillow lava and in particular the facies 2b, 2c and 3 are considered as the subaqueous equivalents of tube-fed pahoehoe. Flow M probably represents a lava lake. Shallowing-upward of the sequence during the built-up of the volcano is indicated by increasing vesicularity of the flows and by an upward increase of the proportion of broken pillow breccia. This increase is gradual from flow 1 to flow 15 but abrupt from flow 15 to 16–19.

Modeling the three‐dimensional structure of macroscopic magma transport systems: Application to Kilauea Volcano, Hawaii

We report the results of modeling the three‐dimensional internal structure of Kilauea's magmatic passageways. The approach uses a clear plexiglass model containing equally‐spaced levels upon which well‐located seismic hypocenters are plotted. Application of constraining geologic and geophysical criteria to this distributed volume of earthquakes permits the interpretation of seismic structures produced by fracturing in response to locally high fluid pressures. Four magma transport and storage structures have been identified within and beneath Kilauea: (1) Primary conduit. The conduit transporting magma into Kilauea's summit storage reservoir rises from the model base (14.6 km) to the 6.5 km depth level. It is a zone of intense fracturing and inferred intrusion, whose horizontal sections are elliptical in planform. Over its height, the average major axis of the component horizontal sections is 3.3 km, with an average minor axis of 1.7 km. This yields an aspect ratio of ξ = 0.52. At the 14.6 km level, the strike of the major axis is N67°E. During passage from the upper mantle through the oceanic crust, this axis rotates in a right‐handed sense, until the strike is N41°W at the 6.5 km level. (2) Magma chamber complex floor. The interval from 6.5 to 5.7 km, immediately over the primary conduit, is aseismic. This suggests differentially high fluid‐to‐rock ratios, and relatively weak pathways for further vertical transport into higher levels of the storage complex, as well as lateral leakage eastward into the Mauna Ulu staging area—for later vertical ascent beneath the upper east rift zone. Seismicity within the immediately subjacent rocks that form the top of the primary conduit (at 6.5 km) suggests that this inferred magma‐rich horizon forms the effective floor of the summit storage complex. (3) Magma chamber crown. Intense seismicity over the 1.1–1.9 km depth interval defines an elliptical region in plan view. The top of this region has a broad apex with an average major axis of 1.5 km, and an average minor axis of 1.1 km producing an aspect ratio of ξ = 0.73. This region coincides with the epicentral position of summit vertical displacement maxima during inflationary deformation and is interpreted as a region of intense diking, crowning the summit storage complex. (4) Upper east rift zone pipe. From a depth of 5.7 km, a cylindrical region of seismicity rises beneath the upper east rift zone, to the 1.9 km level, where it merges with the subhorizontal upper east rift zone duct. This pipe‐like zone has a mean diameter of 1.4 km and a vertical axis that pierces the surface of the volcano at the intersection of the Koae fracture system and the upper east rift zone. We suggest this pipe forms a principal connection between the base of the summit storage reservoir, and near‐surface storage compartments and ducts in the upper east rift zone. In this role, the pipe is suggested to have contributed heavily to Mauna Ulu's magma supply during 1969–1974. The model of magma transport and storage thus constructed provides a context in which other types of data (e.g., ground deformation and electrical conductivity) may be interpreted as well as a means of refining petrological inferences based on lava chemistry.

Bryophytes and Lichens of the Puhimau Geothermal Area, Hawaii Volcanoes National Park

The vegetation of the Puhimau geothermal area was compared with that of the surrounding ecosystem. Very few species of the surrounding area were found with any abundance in the geothermal area. The center of the geothermal area is almost barren. Pockets of vegetation dominated by the endemic moss Campylopus praemorsus (C. Muell.) Jaeg. are throughout the central area. The only other temperature-tolerant species present is Portulaca sclerocarpa Gray. Cladonia oceanica Vain. is commonly found growing epiphytically on the moss away from the high temperatures. The central zone is surrounded by an Andropogon-dominated grassland in which both C. praemorsus and C. oceanica are commonly fertile. No lichens exhibited any tolerance of high temperatures. The Puhimau geothermal area, often referred to locally as the Puhimau Hot Spot, is located on the east rift zone of Kilauea volcano on the island of Hawaii. The area was formed in the winter of 1937-38 when magma came close to the surface and resulted in hydrothermal activity rather than the usual destruction associated with lava flows. The original Metrosideros forest was killed but not burned. The steam vents formed were confined principally to the bases of tree trunks. Some of these trunks are still present in the area and support a distinctive fumarolic community. Although sulphurous gases are normally emitted from fumaroles during the degassing of subterranean lava, no sulphur dioxide or hydrogen sulphide gas has been recorded from the vents in the Puhimau thermal area in recent years (Siegel & Siegel 1979). Recent subterranean volcanic activity in the area resulted in a short (less than 48 hours) emission of SO2. Fosberg and Lamoureux (1966) briefly described the vegetation of two areas of the east rift zone of Kilauea in Hawaii Volcanoes National Park in which there was hydrothermal activity. One of these areas has since been destroyed in the formation of Mauna Ulu. In these areas, they recorded Cladonia cf. cristatella (= C. oceanica Vain.), C. cf. rangi- ferina (= C. skottsbergii Magn.), and Racomitrium (presumably R. lanuginosum var. pruinosum Wils.). Kappen (1973), citing a personal communication from Mueller-Dom- bois, confirmed the presence of these lichens scattered on volcanic soils. Ground tem- peratures from 48 to 89?C have been recorded in both areas, suggesting that all species growing there were remarkably heat tolerant. Although lichens (Lange 1953; Kappen 1973) and mosses (Noerr 1974) are very tolerant of high temperatures when desiccated, when hydrated their tolerance is significantly di- minished. Some mosses are tolerant of temperatures up to 50'C (Noerr 1974) whereas lichens can remain active only up to about 25-30?C (Lange 1965).

Subsurface magma movement detailed at Kilauea and Krafla

Within the last 3 weeks, two major subsurface magma movements have been observed to occur: without major eruption, at Kilauea, Hawaii, and with a small eruption, at Krafla, Iceland. Researchers from Iceland and the U.S. Geological Survey's Hawaiian Volcano Observatory have been able to observe and roughly quantify, by careful instrumental monitoring, the filling of magma chambers from depth and their subsequent draining by intrusive events of eruptions.On March 2, a microearthquake swarm began on Kilauea's upper east rift, near Pauahi Crater, site of a brief eruption in November 1979. Summit deflation, indicating draining of the magma chamber below, started within 7 minutes, and a tiltmeter began to record deformation as magma was intruded near Pauahi, 6 km downrift. About 2000 earthquakes, including several felt events, were recorded before the swarm ended 8 hours later. Deflation of the summit, totaling only 8 mm, continued for another hour. Just over a week later, a second intrusion took place a few kilometers further down the east rift beneath Mauna Ulu, active from 1969 to 1974. Earthquakes began on March 10 at 2157, summit deflation at 2206, and volcanic tremor at 2310. Eight centimeters of deflation, representing the draining of 8×106 m3 of magma from the summit the end of summit deformation on March 12 at 1630. Volcanic tremor around Mauna Ulu waned slowly and had almost ceased by March 13.

Fume compositions found at various stages of activity at Kilauea Volcano, Hawaii

Fume was collected at Kilauea Volcano with equipment patterned after that used in industrial pollution studies. Particulates arid some of the gases present were separated. The fume analyzed was collected from Halemaumau crater in a noneruptive state, from Mauna Ulu lava lake with mild lava fountaining, and from vigorous but short-lived fountaining from fissures across the floor of Kilauea caldera. The chief components were SO2, SO4, Cl, Na, Ca, K, F, Mg, and Fe in about that order of decreasing concentration. Content and order of abundance varied depending on the state of activity of the volcanic sources of the fume. Sulfur compounds were preponderant.

The chemistry of sublimates collected directly from lava fountains at Kilauea Volcano, Hawaii

During 1970, it was occasionally feasible to collect sublimate from directly above the lava fountain in the crater of Mauna Ulu on the east rift zone of Kilauea Volcano, when the level of the lava pool had dropped within the crater. Collecting equipment was suspended down the steep wall to a position above the fountain. Collections were made on quartz wool held within open-ended quartz tubes and, for silica detection, on stainless steel wool in a stainless steel tube. The main components in the sublimate were, in order of decreasing concentration for the best sample, Na, Ca, Al, Fe, Mg, K, B, Si, Ti, Zn, H +, NH 4 +, Cu, Ni in the form of sulfates, chlorides and fluorides. In order to investigate the forms in which the sublimate ions occur under different conditions of temperature and oxidation, the equilibrium compositions of the compounds most likely to be present were calculated. This was done for those important components for which thermodynamic data are available, using a computer program to calculate the minimum free energy for the mixture. The results indicate that, for primary conditions of high temperature and low oxygen partial pressure, the halides were the most likely form of the metallic compounds. Particulate sulfates appear under increasing oxidizing conditions caused by the access of air. These conclusions were reinforced by collections made from holes drilled through the thin crust of a lava lake formed during the same eruption.

Volcanic flame: source of fuel and relation to volcanic gas-lava equilibrium

Flame formation at or near volcanic vents is a somewhat unusual phenomenon, but during October 1970 true flames were observed to issue at intervals from a series of vents in a lava tube or from spatter cones associated with the new eruptive center (Mauna Ulu) on the southeast rift of Kilauea volcano, Hawaii. This situation was similar to that under which successful volcanic gas collections have been made in the past in Hawaii and elsewhere. After several attempts two gas samples were collected successfully between flaming episodes. Analysis showed these to be chiefly water vapor with a small amount of hydrogen and carbon dioxide. The probable source of the hydrogen in the gas is explained on the basis of the high-temperature equilibria involved. The flame-forming properties of dilute mixtures of hydrogen and non-combustible gas were studied and the most dilutemixtures that would produce flames under volcanic conditions were measured (flammability limit). Intermittent flaming can be ascribed to the periodic attainment of the flammability limit for hydrogen in the volcanic gas mixture, which was found to be achieved in one of the collected samples.

Pahoehoe Flows from the 1969–1971 Mauna Ulu Eruption, Kilauea Volcano, Hawaii

Research Article| February 01, 1973 Pahoehoe Flows from the 1969–1971 Mauna Ulu Eruption, Kilauea Volcano, Hawaii DONALD A. SWANSON DONALD A. SWANSON 1U.S. Geological Survey, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar GSA Bulletin (1973) 84 (2): 615–626. https://doi.org/10.1130/0016-7606(1973)84<615:PFFTMU>2.0.CO;2 Article history first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation DONALD A. SWANSON; Pahoehoe Flows from the 1969–1971 Mauna Ulu Eruption, Kilauea Volcano, Hawaii. GSA Bulletin 1973;; 84 (2): 615–626. doi: https://doi.org/10.1130/0016-7606(1973)84<615:PFFTMU>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Note: This paper is dedicated to Aaron and Elizabeth Waters on the occasion of Dr. Waters' retirement.Three types of chemically similar pahoehoe flows were observed to form during the 1969–1971 Mauna Ulu eruption. (1) A cavernous type called shelly pahoehoe, characterized by fragile gas cavities, small tubes, and buckled fragments of surface crust, was deposited when gas-charged lava welled out of the source fissure with little or no accompanying fountaining. (2) A comparatively smooth-surfaced, dense type, characterized by surface channels and only a few large cavities, formed from voluminous flows of partly degassed fallout away from the foot of lava fountains more than 100 m high. (3) A relatively dense type, characterized by hummocky surfaces with abundant low tumuli and overlapping pahoehoe toes and lobes, formed when largely degassed lava issued from tubes after flowing underground for several kilometers or more. Shelly pahoehoe is rarely found in the geologic record, but the other two types occur commonly. These three types of pahoehoe, which are completely intergradational, can be related qualitatively to the relative gas content and mode of flowage of the lava. The present surface of Kilauea is underlain mostly by hummocky, tube-fed pahoehoe. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

A naturally occurring model of global plate tectonics

During the Mauna Ulu eruption at Kilauea volcano, Hawaii, a crust-veneered lava column in the central eruptive vent provided an active model of global plate tectonics. As the crust migrated from one end of the vent to the other, it became segmented into plates, which were invariably bounded by some combination of rises, sinks and transform faults. If it is assumed that inertial forces associated with plate tectonics are diminishingly small, a quantitative comparison suggests that the two situations were scaled equivalents for some features. The exact degree of similarity between the two situations, however, is limited, chiefly by the present incomplete state of understanding of both environments. There are differences in detail between the plate tectonics on the surface of the lava column and those on the surface of the earth, but examination of the lava column provides an excellent teaching aid that may prove to be a valuable tool in the continuing studies of crustal plates and their motions for the earth.

Pillow Lava and Pahoehoe: A Reply

Previous articleNext article No AccessDiscussion and ReplyPillow Lava and Pahoehoe: A ReplyJ. G. JonesJ. G. Jones Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Journal of Geology Volume 77, Number 6Nov., 1969 Article DOIhttps://doi.org/10.1086/627472 Views: 3Total views on this site Citations: 5Citations are reported from Crossref Copyright 1969 The University of ChicagoPDF download Crossref reports the following articles citing this article:Jeffrey M. Byrnes, David A. Crown Relationships between pahoehoe surface units, topography, and lava tubes at Mauna Ulu, Kilauea Volcano, Hawaii, Journal of Geophysical Research: Solid Earth 106, no.B2B2 (Feb 2001): 2139–2151.https://doi.org/10.1029/2000JB900369Michael J Kennish, Richard A Lutz Morphology and distribution of lava flows on mid-ocean ridges: a review, Earth-Science Reviews 43, no.3-43-4 (May 1998): 63–90.https://doi.org/10.1016/S0012-8252(98)00006-3Robert D. Ballard, Robin T. Holcomb, Tjeerd H. van Andel The Galapagos Rift at 86° W: 3. Sheet flows, collapse pits, and lava lakes of the Rift Valley, Journal of Geophysical Research 84, no.B10B10 (Jan 1979): 5407.https://doi.org/10.1029/JB084iB10p05407M. Vuagnat Pillow lava flows: Isolated sacks or connected tubes?, Bulletin Volcanologique 39, no.44 (Dec 1975): 581–589.https://doi.org/10.1007/BF02596978 J. G. Jones Intraglacial Volcanoes of the Laugarvatn Region, Southwest Iceland, II, The Journal of Geology 78, no.22 (Sep 2015): 127–140.https://doi.org/10.1086/627496