10,326
edits
Changes
Jump to navigation
Jump to search
Line 78:
Line 78: − + + + − − [[File:UNN_Medical_Geology_Fig_4.png|thumb|400px|{{figure number|4}}]]
→Geochemobiological Pathways
===Geochemobiological Pathways===
===Geochemobiological Pathways===
This is the rock-soil-plant-animal/human pathway, and it is of major importance in the study of medical geology. It describes the various ways through which people can come in contact with elements originally in the rocks (Skinner, 2007), (Fig. 4).
[[File:UNN_Medical_Geology_Fig_4.png|thumb|400px|{{figure number|4}}The continuum of Earth materials between the atmosphere, hydrosphere and lithosphere and the pathways for uptake of particles, gases, and elements into plants, animals and humans (after Skinner, 2007).]]
This is the rock-soil-plant-animal/human pathway, and it is of major importance in the study of medical geology. It describes the various ways through which people can come in contact with elements originally in the rocks (Skinner, 2007), ([[:File:UNN_Medical_Geology_Fig_4.png|Figure 4]]).
Elements are released from rocks through weathering− the process by which rocks are broken down into smaller components.
Elements are released from rocks through weathering− the process by which rocks are broken down into smaller components.
Physical weathering is the process by which rocks are broken down into smaller chunks without altering its mineral content. It occurs through temperature changes and by the action of the wind. Temperature variation leads to the development of flakes on the rocks whose removal exposes subsequent layers to further heating and cooling and, then, to chemical weathering. Physical disintegration of rocks is also caused by the action of burrowing animals and plant roots. Freezing of water in crevices of rocks is another force that disintegrates rocks making them prone to chemical weathering (Selinus et al, 2010).
Physical weathering is the process by which rocks are broken down into smaller chunks without altering its mineral content. It occurs through temperature changes and by the action of the wind. Temperature variation leads to the development of flakes on the rocks whose removal exposes subsequent layers to further heating and cooling and, then, to chemical weathering. Physical disintegration of rocks is also caused by the action of burrowing animals and plant roots. Freezing of water in crevices of rocks is another force that disintegrates rocks making them prone to chemical weathering (Selinus et al, 2010).