A drop in the elevation of the surface of the land is called land subsidence, and can be caused by a collapse of underground mining shafts or naturally occurring underground cave system collapses, commonly called sinkholes.
In the US, subsidized stafford student loans refer to loans that do not accrue interest while a student is in deferment. One example of a deferment period is when the student is enrolled in school.
Subsidence (sink holes & other manifestations of land-form depression) may occur from any of several conditions. Examples of some of these are:
Natural Causes:
Rapid, or prolonged, depression of groundwater level;
Faulting (earth quakes);
Isostatic (weight of mountains, oceans, lakes, and glaciers);
Dissolution of limestone substrate (cave formation);
Human Causes:
Extraction of archaic water;
Extraction of oil;
Extraction of natural gas;
Shaft mining, especially irresponsible operations;
Extraction of geothermal energy;
The gradual caving in or sinking of an area of land.
To subsidize means to pay a portion of a bill or to aid in financing of money. The government subsidizes money for low income housing and student aid for example.
The definition of subsidence is the decreasing or caving in of an area of land. A real world example of a subsidence would be a sink hole, having the land sink in gradually.
Water in the ground occupies the volume between the individual grains of material in the rock or soil from which the ground is composed. Thus wet clay, for example, will shrink in volume as it drys out and cracks may appear too. A similar thing will occur if groundwater is removed and the land dries out - it will shrink (subsidence) and cracks may also appear.
subsidence.
subsidence
subsidence sinkholes are different from collapse sinkholes in two ways . first,subsidence sinkholes ocer when there is almost no overburn,or material,above the limestone. collapse sinkholes happen when there is thick overburn. secondly, subsidence sinkholes occur slowly, over time, while collapse foms quckly beacause of human activity , such as well drilling.
The definition of subsidence is the decreasing or caving in of an area of land. A real world example of a subsidence would be a sink hole, having the land sink in gradually.
underground coal mining
Subsidence inversion is a meteorological term. They occur when a large mass of warm air enters an area trapping cooler air beneath.
Subsidence occurs when one plate is denser than the plate it is moving into. It then slips under the less dense plate and melts into the mantle.
Water in the ground occupies the volume between the individual grains of material in the rock or soil from which the ground is composed. Thus wet clay, for example, will shrink in volume as it drys out and cracks may appear too. A similar thing will occur if groundwater is removed and the land dries out - it will shrink (subsidence) and cracks may also appear.
subsidence.
Uplift and subsidence of large land masses without significant deformation.
subsidence
subsidence
subsidence sinkholes are different from collapse sinkholes in two ways . first,subsidence sinkholes ocer when there is almost no overburn,or material,above the limestone. collapse sinkholes happen when there is thick overburn. secondly, subsidence sinkholes occur slowly, over time, while collapse foms quckly beacause of human activity , such as well drilling.
survey the land or entire area with surveying equipment, look at previously recorded survey data from over the years, compare your findings with those previously taken, to see what the rate of subsidence is for the area.
The removal of water from aquifers, such as fine grained sediments. The rock compacts because water is partly responsible for holding the ground up, and when the water is removed, the rock falls on itself.An excessive extraction of groundwater is the primary reason for land subsidence. This is particularly a problem in the southwestern United States.