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Cracks and pores: a closer look.
Science (New York, N.Y.)
|October 13, 1972
Summary
New rock imaging reveals that most pores and cracks originated early in the rock's history. This finding suggests laboratory measurements accurately predict rock behavior in the Earth's crust, crucial for understanding microporosity.
Area of Science:
- Geology
- Materials Science
- Geophysics
Background:
- Rock properties like electrical resistivity and permeability are influenced by internal structures such as pores and cracks.
- Understanding the origin and evolution of these structures is key to predicting rock behavior under subsurface conditions.
Purpose of the Study:
- To investigate the origin of pores and cracks in rocks.
- To assess the reliability of laboratory measurements for predicting in-situ rock properties.
Main Methods:
- Direct visualization of rock microstructures using a novel imaging technique.
- Analysis of the shapes and distribution of pores and cracks.
Main Results:
- The study observed that the majority of pores and some cracks exhibit shapes indicative of formation early in the rock's geological history.
- These early-formed structures appear to significantly influence the rock's overall microporosity.
Conclusions:
- The morphology of rock microstructures suggests an early origin, potentially during or shortly after rock formation.
- Laboratory-based measurements of rock properties (e.g., electrical resistivity, permeability) are likely reliable indicators of their behavior within the Earth's crust due to the persistent nature of these early-formed features.
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