rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    title: Crack healing as a function of pOH⁻ and fracture morphology
  name:
    name part: Fallon, Jessica Anne, 1978-
    role:
      role term: creator
  name:
    name part: Kronenberg, Andreas K.
    role:
      role term: thesis advisor.
  name:
    name part: Lamb, William
    role:
      role term: thesis advisor.
  type of resource: text
  genre: bibliography
  origin info:
    place:
      place term: txu
    date issued: 2005
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: electronic
    form: remote
  abstract: Crack healing in quartz has been investigated by optical microscopy and interferometry of rhombohedral ( 1 0 1̄ 1 ) cracks in polished Brazilian quartz prisms that were annealed hydrothermally at temperatures of 250⁰C and 400⁰C for 2.4 to 240 hours, fluid pressure P[subscript f] = P[subscript c] = 41 MP[subscript a], and varying pOH⁻ (from 5.4 to 1.2 at 250⁰C for fluids consisting of distilled water and NaOH solutions with molalities up to 1). Crack morphologies before and after annealing were recorded for each sample in plane light digital images. Crack apertures were determined from interference fringes recorded using transmitted monochromatic light ([lambda]= 598 nm). As documented in previous studies, crack healing is driven by reductions in surface energy and healing rates are governed by diffusional transport; sharply defined crack tips become blunted and split into fluid-filled tubes and inclusions. A rich variety of fluid inclusion geometries are also observed with nonequilibrium shapes that depend on initial surface roughness. Crack healing is significant at T=400⁰C. Crack healing is also observed at T=250⁰C for smooth cracks with apertures <0.6 mm or cracks subject to low pOH ⁻. The extent of crack healing is sensitive to crack aperture and to hackles formed by fine-scale crack branching during earlier crack growth. Crack apertures appear to be controlled by hackles and debris, which prop the crack surfaces open. Upon annealing, crack apertures are reduced, and these reduced crack apertures govern the kinetics of diffusional crack healing that follows. Hackles are sites of either enhanced or reduced loss of fluid-solid interface, depending on slight mismatches and sense of twist on opposing crack surfaces. Hackles are replaced either by healed curvilinear quartz bridges and river patterns surrounded by open fluid-filled crack, or by fluid- filled tubes surrounded by regions of healed quartz. For a given temperature, aperture and anneal time, crack healing …
  note: "Major Subject: Geology"
  note: Title from author supplied metadata (automated record created on Feb. 17, 2005.)
  note: Vita.
  note: Abstract.
  note: Electronic resource] / by Jessica Anne Fallon.
  note: Mode of access: World Wide Web.
  note: System requirements: World Wide Web access and Adobe Acrobat Reader.
  note: M. S. Texas A&M University 2004
  note: Includes bibliographical references.
  note: Text (Thesis).
  subject:
    topic: Major Geology
  subject:
    topic: quartz
  subject:
    topic: crack healing
  subject:
    topic: fracture morphology
  subject:
    topic: fluid inclusions
  identifier: http://hdl.handle.net/1969.1/1369
  record info:
    record content source: TXA
    record creation date: 050503
    record change date: 20151101063045.0
    record identifier: in00002057277