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Greenberger RN, Harris M, Ehlmann BL, Crotteau MA, Kelemen PB, Manning CE, Teagle DAH. Hydrothermal Alteration of the Ocean Crust and Patterns in Mineralization With Depth as Measured by Micro-Imaging Infrared Spectroscopy. JOURNAL OF GEOPHYSICAL RESEARCH. SOLID EARTH 2021; 126:e2021JB021976. [PMID: 34595085 PMCID: PMC8459238 DOI: 10.1029/2021jb021976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 06/24/2021] [Accepted: 07/11/2021] [Indexed: 06/13/2023]
Abstract
Processes for formation, cooling, and altering Earth's ocean crust are not yet completely understood due to challenges in access and sampling. Here, we use contiguous micro-imaging infrared spectroscopy to develop complete-core maps of mineral occurrence and investigate spatial patterns in the hydrothermal alteration of 1.2 km of oceanic crust recovered from Oman Drilling Project Holes GT1A, GT2A, and GT3A drilled in the Samail Ophiolite, Oman. The imaging spectrometer shortwave infrared sensor measured reflectance of light at wavelengths 1.0-2.6 μm at 250-260 μm/pixel, resulting in >1 billion independent measurements. We map distributions of nine key primary and secondary minerals/mineral groups-clinopyroxene, amphibole, calcite, chlorite, epidote, gypsum, kaolinite/montmorillonite, prehnite, and zeolite-and find differences in their spatial occurrences and pervasiveness. Accuracy of spectral mapping of occurrence is 68%-100%, established using X-ray diffraction measurements from the core description. The sheeted dikes and gabbros of upper oceanic crust Hole GT3A show more pervasive alteration and alteration dominated by chlorite, amphibole, and epidote. The foliated/layered gabbros of GT2A from intermediate crustal depths have similarly widespread chlorite but more zeolite and little amphibole and epidote. The layered gabbros of the lower oceanic crust (GT1A) have remnant pyroxene and 2X less chlorite, but alteration is extensive within and surrounding major fault zones with widespread occurrences of amphibole. The results indicate greater distribution of higher temperature alteration minerals in the upper oceanic crust relative to deeper gabbros and highlight the importance of fault zones in hydrothermal convection in the lower ocean crust.
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Affiliation(s)
- Rebecca N. Greenberger
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Michelle Harris
- School of Geography, Earth, and Environmental SciencesPlymouth UniversityPlymouthUK
| | - Bethany L. Ehlmann
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Molly A. Crotteau
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Peter B. Kelemen
- Department of Earth & Environmental SciencesLamont‐Doherty Earth ObservatoryColumbia UniversityPalisadesNYUSA
| | - Craig E. Manning
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - Damon A. H. Teagle
- School of Ocean and Earth ScienceNational Oceanography Centre SouthamptonUniversity of SouthamptonSouthamptonUK
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Structure of Modern Oceanic Crust and Ophiolites and Implications for Faulting and Magmatism at Oceanic Spreading Centers. ACTA ACUST UNITED AC 2013. [DOI: 10.1029/gm106p0219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Cudrak CF, Clowes RM. Crustal structure of Endeavour Ridge Segment, Juan de Fuca Ridge, from a detailed seismic refraction survey. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/92jb02860] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Quick JE, Denlinger RP. Ductile deformation and the origin of layered gabbro in ophiolites. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/93jb00698] [Citation(s) in RCA: 147] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Shaw PR. Age variations of oceanic crust Poisson's ratio: Inversion and a porosity evolution model. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/93jb02109] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Pallister JS, Hopson CA. Samail Ophiolite plutonic suite: Field relations, phase variation, cryptic variation and layering, and a model of a spreading ridge magma chamber. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jb086ib04p02593] [Citation(s) in RCA: 393] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Ryan MP. Neutral buoyancy and the structure of mid-ocean ridge magma reservoirs. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/93jb02394] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Bjarnason IT, Menke W, Flóvenz ÓG, Caress D. Tomographic image of the Mid-Atlantic Plate Boundary in southwestern Iceland. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/92jb02412] [Citation(s) in RCA: 151] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hale LD, Thompson GA. The seismic reflection character of the continental mohorovicic discontinuity. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jb087ib06p04625] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Stakes DS, Shervais JW, Hopson CA. The volcanic-tectonic cycle of the FAMOUS and AMAR Valleys, Mid-Atlantic Ridge (36°47′N): Evidence from basalt glass and phenocryst compositional variations for a steady state magma chamber beneath the valley midsections, AMAR 3. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jb089ib08p06995] [Citation(s) in RCA: 141] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Chian D, Louden KE. The continent-ocean crustal transition across the southwest Greenland margin. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/93jb03404] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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White DJ, Clowes RM. Seismic attenuation structure beneath the Juan de Fuca Ridge from tomographic inversion of amplitudes. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/93jb02039] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Fuis GS, Mooney WD, Healy JH, McMechan GA, Lutter WJ. A seismic refraction survey of the Imperial Valley Region, California. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jb089ib02p01165] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Robinson PT, Hall JM, Christensen NI, Gibson IL, Fridleifsson IB, Schmincke HU, Schonharting G. The Iceland Research Drilling Project: Synthesis of results and implications for the nature of Icelandic and oceanic crust. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jb087ib08p06657] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Karson JA, Fox PJ. Geological and geophysical investigation of the Mid-Cayman Spreading Centre: seismic velocity measurements and implications for the constitution of layer 3. ACTA ACUST UNITED AC 2010. [DOI: 10.1111/j.1365-246x.1986.tb04520.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Carlson RL, Jay Miller D. Influence of pressure and mineralogy on seismic velocities in oceanic gabbros: Implications for the composition and state of the lower oceanic crust. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003jb002699] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- R. L. Carlson
- Department of Geology and Geophysics; Texas A&M University; College Station Texas USA
| | - D. Jay Miller
- Department of Geology and Geophysics and Ocean Drilling Program; Texas A&M University; College Station Texas USA
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Crawford WC, Hildebrand JA, Dorman LM, Webb SC, Wiens DA. Tonga Ridge and Lau Basin crustal structure from seismic refraction data. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2001jb001435] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | | | - LeRoy M. Dorman
- Scripps Institution of Oceanography; La Jolla California USA
| | - Spahr C. Webb
- Lamont Doherty Earth Observatory; Palisades New York USA
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Korenaga J, Kelemen PB, Holbrook WS. Methods for resolving the origin of large igneous provinces from crustal seismology. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001jb001030] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jun Korenaga
- Department of Earth, Atmospheric, and Planetary Sciences; Massachusetts Institute of Technology; Cambridge Massachusetts USA
| | - Peter B. Kelemen
- Department of Geology and Geophysics; Woods Hole Oceanographic Institution; Woods Hole Massachusetts USA
| | - W. Steven Holbrook
- Department of Geology and Geophysics; University of Wyoming; Laramie Wyoming USA
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Korenaga J, Holbrook WS, Detrick RS, Kelemen PB. Gravity anomalies and crustal structure at the southeast Greenland margin. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000jb900416] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Feigl KL, Gasperi J, Sigmundsson F, Rigo A. Crustal deformation near Hengill volcano, Iceland 1993-1998: Coupling between magmatic activity and faulting inferred from elastic modeling of satellite radar interferograms. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/2000jb900209] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Canales JP, Detrick RS, Lin J, Collins JA, Toomey DR. Crustal and upper mantle seismic structure beneath the rift mountains and across a nontransform offset at the Mid-Atlantic Ridge (35°N). ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999jb900379] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Barth GA, Mutter JC. Variability in oceanic crustal thickness and structure: Multichannel seismic reflection results from the northern East Pacific Rise. ACTA ACUST UNITED AC 1996. [DOI: 10.1029/96jb00814] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Suyehiro K, Takahashi N, Ariie Y, Yokoi Y, Hino R, Shinohara M, Kanazawa T, Hirata N, Tokuyama H, Taira A. Continental Crust, Crustal Underplating, and Low-
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Upper Mantle Beneath an Oceanic Island Arc. Science 1996. [DOI: 10.1126/science.272.5260.390] [Citation(s) in RCA: 282] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Kiyoshi Suyehiro
- K. Suyehiro, N. Takahashi, Y. Ariie, Y. Yokoi, H. Tokuyama, A. Taira, Ocean Research Institute, University of Tokyo, Tokyo 164, Japan
| | - Narumi Takahashi
- K. Suyehiro, N. Takahashi, Y. Ariie, Y. Yokoi, H. Tokuyama, A. Taira, Ocean Research Institute, University of Tokyo, Tokyo 164, Japan
| | - Yoshiro Ariie
- K. Suyehiro, N. Takahashi, Y. Ariie, Y. Yokoi, H. Tokuyama, A. Taira, Ocean Research Institute, University of Tokyo, Tokyo 164, Japan
| | - Yasutaka Yokoi
- K. Suyehiro, N. Takahashi, Y. Ariie, Y. Yokoi, H. Tokuyama, A. Taira, Ocean Research Institute, University of Tokyo, Tokyo 164, Japan
| | - Ryota Hino
- R. Hino, Faculty of Science, Tohoku University, Sendai 981, Japan
| | - Masanao Shinohara
- M. Shinohara, Department of Earth Sciences, Chiba University, Chiba 263, Japan
| | - Toshihiko Kanazawa
- T. Kanazawa and N. Hirata, Earthquake Research Institute, University of Tokyo, Tokyo 113, Japan
| | - Naoshi Hirata
- T. Kanazawa and N. Hirata, Earthquake Research Institute, University of Tokyo, Tokyo 113, Japan
| | - Hidekazu Tokuyama
- K. Suyehiro, N. Takahashi, Y. Ariie, Y. Yokoi, H. Tokuyama, A. Taira, Ocean Research Institute, University of Tokyo, Tokyo 164, Japan
| | - Asahiko Taira
- K. Suyehiro, N. Takahashi, Y. Ariie, Y. Yokoi, H. Tokuyama, A. Taira, Ocean Research Institute, University of Tokyo, Tokyo 164, Japan
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Detrick R, Collins J, Stephen R, Swift S. In situ evidence for the nature of the seismic layer 2/3 boundary in oceanic crust. Nature 1994. [DOI: 10.1038/370288a0] [Citation(s) in RCA: 136] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Morgan JP, Harding A, Orcutt J, Kent G, Chen Y. Chapter 7 An Observational and Theoretical Synthesis of Magma Chamber Geometry and Crustal Genesis along a Mid-ocean Ridge Spreading Center. ACTA ACUST UNITED AC 1994. [DOI: 10.1016/s0074-6142(09)60095-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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Minshull TA, White RS, Mutter JC, Buhl P, Detrick RS, Williams CA, Morris E. Crustal structure at the Blake Spur Fracture Zone from expanding spread profiles. ACTA ACUST UNITED AC 1991. [DOI: 10.1029/91jb00431] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hacker BR. Simulation of the metamorphic and deformational history of the metamorphic sole of the Oman Ophiolite. ACTA ACUST UNITED AC 1990. [DOI: 10.1029/jb095ib04p04895] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Carlson RL, Herrick CN. Densities and porosities in the oceanic crust and their variations with depth and age. ACTA ACUST UNITED AC 1990. [DOI: 10.1029/jb095ib06p09153] [Citation(s) in RCA: 224] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Seismic anisotropy and age-dependent structure of the upper oceanic crust. ACTA ACUST UNITED AC 1989. [DOI: 10.1029/gm057p0001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Collins JA, Purdy MG, Brocher TM. Seismic velocity structure at Deep Sea Drilling Project site 504B, Panama Basin: Evidence for thin oceanic crust. ACTA ACUST UNITED AC 1989. [DOI: 10.1029/jb094ib07p09283] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Nicolas A, Christensen NI. Formation of anisotropy in upper mantle peridotites: A review. COMPOSITION, STRUCTURE AND DYNAMICS OF THE LITHOSPHERE‐ASTHENOSPHERE SYSTEM 1987. [DOI: 10.1029/gd016p0111] [Citation(s) in RCA: 374] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
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Gettings ME, Blank HR, Mooney WD, Healey JH. Crustal structure of southwestern Saudi Arabia. ACTA ACUST UNITED AC 1986. [DOI: 10.1029/jb091ib06p06491] [Citation(s) in RCA: 158] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Mutter JC, Talwani M, Stoffa PL. Evidence for a thick oceanic crust adjacent to the Norwegian Margin. ACTA ACUST UNITED AC 1984. [DOI: 10.1029/jb089ib01p00483] [Citation(s) in RCA: 121] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Lewis BTR, Garmany JD. Constraints on the structure of the East Pacific Rise from seismic refraction data. ACTA ACUST UNITED AC 1982. [DOI: 10.1029/jb087ib10p08417] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kempner WC, Gettrust JF. Ophiolites, synthetic seismograms, and oceanic crustal structure: 2. A comparison of synthetic seismograms of the Samail Ophiolite, Oman, and the ROSE refraction data from the East Pacific Rise. ACTA ACUST UNITED AC 1982. [DOI: 10.1029/jb087ib10p08463] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hale LD, Morton CJ, Sleep NH. Reinterpretation of seismic reflection data over the East Pacific Rise. ACTA ACUST UNITED AC 1982. [DOI: 10.1029/jb087ib09p07707] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Gettrust JF, Furukawa K, Kempner WB. Variation in young oceanic crust and upper mantle structure. ACTA ACUST UNITED AC 1982. [DOI: 10.1029/jb087ib10p08435] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
Independent geological and geophysical investigations of the Mid-Ocean Ridge system have begun to focus on the nature of the magma chamber system underlying its central axis. Thermal models predict the existence of a steady-state chamber beneath a thin crustal lid ranging in thickness from 2 to 13 kilometers. The only aspect of the system that these models fail to account for is the extremely slow spreading rates. Seismological studies reveal the existence of a low-velocity zone beneath segments of the East Pacific Rise, which is thought to correspond to a chamber system having a half-width of approximately 5 to 10 kilometers. These estimates compare favorably with those derived separately through petrological investigations of deep-sea drilling results, various sampling programs, and field and laboratory studies of ophiolites. The chamber is thought to be wing-shaped and to remain continuously open; it is thought to be fed from the center while simultaneously solidifying at the sides as spreading carries the two halves apart. Progressive fractionation occurs by crystal settling coupled with repeated replenishment and magma mixing in an open steady-state system. Near-bottom studies reveal that the zone of extrusion above the chamber is narrow, but its eruptive history is cyclic in nature, in conflict with the predictions of a steady-state model. On-bottom gravity data at 21 degrees N on the East Pacific Rise reveal a negative gravity anomaly that may be related to the uppermost part of the chamber. The anomaly is only 2 kilometers wide and 1 kilometer below the sea floor. This feature may be associated with a short-term upper magma reservoir. The cyclic volcanic activity is directly related to the active phase of hydrothermal circulation responsible for the observed negative thermal anomaly. The volume of water associated with this circulation is equal to the entire ocean volume passing through the accretion zone approximately every 8 million years. This is about 0.5 percent of the world's rivers, but the effective transport rates of elements are comparable to those of rivers in that anomalies for individual elements are frequently between 100 and 1000 times the average river composition. The degree of subsurface dilution determines the final exit temperature and composition of the hydrothermal fluids, ranging from manganese domination at extreme dilution to iron at intermediate levels to sulfide deposition when low dilution occurs. The discovery of massive sulfide deposits on the East Pacific Rise is destined to have a profound impact on our understanding of ore-forming processes. Whether it will have any economic significance remains to be seen.
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