Health Benefi ts of Geologic Materials and Geologic Processes

In this paper, I argue that encounters with hydrogeologic processes encourage feminists to rethink the permeable surfaces between human bodies, ecological systems, and political events. Contemporary geographical accounts of environmental knowledge controversies are insufficiently attentive to how geologic processes exceed and undermine instrumental deliberative political solutions to environmental problems. Through a mobilization of feminist geophilosophy, I argue instead that the limits of instrumental knowledge are not merely produced by uncertainty or lack of evidence, but by the inhuman forces that condition feminist thinking itself. An investigation of a controversy surrounding the permeability of underground materials near a proposed in situ recovery uranium mine in South Dakota demonstrates that subterranean spaces have the ability to heighten a sense of the openness of our bodies to geological forces. Public and expert testimony of the hydrogeology of the region creatively extended scientific accounts to draw conclusions about the meaning and force of geology for the politics of uranium extraction. This essay contributes a unique account of environmental controversies in which materiality does not become instrumental or experiential knowledge but instead produces a creative understanding of permeable geologic materials which provokes feminist thought.

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A method to measure pores and fissures in geologic materials under S.E.M. by digital image processing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108209 ◽

1978 ◽

Vol 36 (1) ◽

pp. 212-213

Author(s):

L. Montoto ◽

M. Montoto ◽

A. Bel-Lan

Keyword(s):

Image Processing ◽

Optical Microscopy ◽

Digital Image Processing ◽

Digital Image ◽

Digital Processing ◽

Free Surfaces ◽

Geologic Materials ◽

Automatic Information ◽

Detector Output ◽

Rock Specimens

INTRODUCTION.- The physical properties of rock masses are greatly influenced by their internal discontinuities, like pores and fissures. So, these need to be measured as a basis for interpretation. To avoid the basic difficulties of measurement under optical microscopy and analogic image systems, the authors use S.E.M. and multiband digital image processing. In S.E.M., analog signal processing has been used to further image enhancement (1), but automatic information extraction can be achieved by simple digital processing of S.E.M. images (2). The use of multiband image would overcome difficulties such as artifacts introduced by the relative positions of sample and detector or the typicals encountered in optical microscopy.DIGITAL IMAGE PROCESSING.- The studied rock specimens were in the form of flat deformation-free surfaces observed under a Phillips SEM model 500. The SEM detector output signal was recorded in picture form in b&w negatives and digitized using a Perkin Elmer 1010 MP flat microdensitometer.

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Phanerozoic Oxygen

10.23943/princeton/9780691145020.003.0011 ◽

2017 ◽

Author(s):

Donald Eugene Canfield

Keyword(s):

Oxygen Consumption ◽

Organic Carbon ◽

Sea Level ◽

Time Scale ◽

Atmospheric Oxygen ◽

Sea Level Change ◽

Oxygen Production ◽

Level Change ◽

History Of ◽

Geologic Processes

This chapter discusses the modeling of the history of atmospheric oxygen. The most recently deposited sediments will also be the most prone to weathering through processes like sea-level change or uplift of the land. Thus, through rapid recycling, high rates of oxygen production through the burial of organic-rich sediments will quickly lead to high rates of oxygen consumption through the exposure of these organic-rich sediments to weathering. From a modeling perspective, rapid recycling helps to dampen oxygen changes. This is important because the fluxes of oxygen through the atmosphere during organic carbon and pyrite burial, and by weathering, are huge compared to the relatively small amounts of oxygen in the atmosphere. Thus, all of the oxygen in the present atmosphere is cycled through geologic processes of oxygen liberation (organic carbon and pyrite burial) and consumption (weathering) on a time scale of about 2 to 3 million years.

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