Abstract
Some of the hydrogeological implications of construction and operation of oil and gas pipelines in northern regions of Canada are considered in relation to their potential environmental impacts and those factors affecting the security of the pipeline itself. Although the extent to which water in permafrost participates in the subsurface flow regime has not been fully demonstrated, the role of liquid as well as vapor transport in frozen earth materials can be shown from theory to be highly significant; water movement rates in frozen soil are on the same order as those in unsaturated, unfrozen soil. Below 0/sup 0/C, the unfrozen water content in a fine-grained porous medium is dependent on temperature but independent of the total water content. The thermal gradient controls the rate and direction of water movement in permafrost. The groundwater stabilizes the streamflow and in the absence of large lakes provides the main source of flow during the winter. As groundwater is frequently confined by the permafrost, degradation of the permafrost can have significant consequences. The thaw bulb formed around a hot oil pipeline can induce liquefactioned flow of the thawed material. A chilled pipeline could restrict groundwater movement, resulting in buildup of artesian conditions and
More>>
Citation Formats
Harlan, R L.
Hydrogeological considerations in northern pipeline development. [Permafrost affected by hot or chilled pipeline].
Canada: N. p.,
1974.
Web.
Harlan, R L.
Hydrogeological considerations in northern pipeline development. [Permafrost affected by hot or chilled pipeline].
Canada.
Harlan, R L.
1974.
"Hydrogeological considerations in northern pipeline development. [Permafrost affected by hot or chilled pipeline]."
Canada.
@misc{etde_8170091,
title = {Hydrogeological considerations in northern pipeline development. [Permafrost affected by hot or chilled pipeline]}
author = {Harlan, R L}
abstractNote = {Some of the hydrogeological implications of construction and operation of oil and gas pipelines in northern regions of Canada are considered in relation to their potential environmental impacts and those factors affecting the security of the pipeline itself. Although the extent to which water in permafrost participates in the subsurface flow regime has not been fully demonstrated, the role of liquid as well as vapor transport in frozen earth materials can be shown from theory to be highly significant; water movement rates in frozen soil are on the same order as those in unsaturated, unfrozen soil. Below 0/sup 0/C, the unfrozen water content in a fine-grained porous medium is dependent on temperature but independent of the total water content. The thermal gradient controls the rate and direction of water movement in permafrost. The groundwater stabilizes the streamflow and in the absence of large lakes provides the main source of flow during the winter. As groundwater is frequently confined by the permafrost, degradation of the permafrost can have significant consequences. The thaw bulb formed around a hot oil pipeline can induce liquefactioned flow of the thawed material. A chilled pipeline could restrict groundwater movement, resulting in buildup of artesian conditions and icings. The liberation and absorption of latent heat on freezing and thawing affects the thermal regime in the ground surface. Recommendations are given for pipeline construction and areas for further study pointed out. (DLC)}
place = {Canada}
year = {1974}
month = {Nov}
}
title = {Hydrogeological considerations in northern pipeline development. [Permafrost affected by hot or chilled pipeline]}
author = {Harlan, R L}
abstractNote = {Some of the hydrogeological implications of construction and operation of oil and gas pipelines in northern regions of Canada are considered in relation to their potential environmental impacts and those factors affecting the security of the pipeline itself. Although the extent to which water in permafrost participates in the subsurface flow regime has not been fully demonstrated, the role of liquid as well as vapor transport in frozen earth materials can be shown from theory to be highly significant; water movement rates in frozen soil are on the same order as those in unsaturated, unfrozen soil. Below 0/sup 0/C, the unfrozen water content in a fine-grained porous medium is dependent on temperature but independent of the total water content. The thermal gradient controls the rate and direction of water movement in permafrost. The groundwater stabilizes the streamflow and in the absence of large lakes provides the main source of flow during the winter. As groundwater is frequently confined by the permafrost, degradation of the permafrost can have significant consequences. The thaw bulb formed around a hot oil pipeline can induce liquefactioned flow of the thawed material. A chilled pipeline could restrict groundwater movement, resulting in buildup of artesian conditions and icings. The liberation and absorption of latent heat on freezing and thawing affects the thermal regime in the ground surface. Recommendations are given for pipeline construction and areas for further study pointed out. (DLC)}
place = {Canada}
year = {1974}
month = {Nov}
}