Basalt samples dredged from the ocean floor were experimentally fractured in tension while being observed microscopically. Five basaltic textural types were chosen: (1) cotectic crystallization of olivine, plagioclase, and pyroxene Juan de Fuca, (2) dark glass matrix with phenocrysts of plagioclase and clinopyroxene Gorda Ridge, (3) vesicular black glass matrix with trachytic micro-phenocrysts Mid Atlantic Ridge Rift Valley, (4) black glass pillow with an hollow-centered phenocrysts Mid Atlantic Ridge Rift Valley, (5) black glass matrix with micro-phenocrysts of olivine, pyroxene, plagioclase Mid Atlantic Ridge Rift Valley. Fracturing was done in the ¼ inch direction of precisely machined chips 1 x ¾ x ¾ inches. Test conditions were dry at 20°C, wet at 20°c, and 300°c. Modal integration of the crack path length and general modal analyses indicate that regardless of texture or test parameter: (1) the fracture path seeks out voids, glass, and grain boundaries to the exclusion of mineral grain cleavage, (2) a propagating fracture is offset by pre-existing fractures perpendicular to the propagation direction, (3) within the locus of the propagation direction, a propagating fracture coalesces with a pre-existing parallel or sub-parallel fracture. The off-setting behavior of pre-existing fractures for newer fractures bears a striking geometric resemblance to the Mid Atlantic Ridge and its transform faults. / Earth and Environmental Science
| Identifer | oai:union.ndltd.org:TEMPLE/oai:scholarshare.temple.edu:20.500.12613/8425 |
| Date | January 1972 |
| Creators | Koons, Mary-Linda |
| Contributors | Ulmer, Gene Carleton, 1937-2015, Myer, George H., Platt, Lucian B., 1931- |
| Publisher | Temple University. Libraries |
| Source Sets | Temple University |
| Language | English |
| Detected Language | English |
| Type | Thesis/Dissertation, Image |
| Format | 96 pages |
| Rights | IN COPYRIGHT- This Rights Statement can be used for an Item that is in copyright. Using this statement implies that the organization making this Item available has determined that the Item is in copyright and either is the rights-holder, has obtained permission from the rights-holder(s) to make their Work(s) available, or makes the Item available under an exception or limitation to copyright (including Fair Use) that entitles it to make the Item available., http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | http://dx.doi.org/10.34944/dspace/8389, Digital copy of print original., Theses and Dissertations |
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