Springs Discharging Groundwater in the Grand Canyon
This photo shows groundwater discharging from springs in the Redwall Limestone wall of the Grand Canyon at Vasey's Paradise, Arizona, USA into the Colorado River. The limestone composition of the underground rock and the layering and fracturing of the aquifers in this area allow for water to move relatively quickly downgradient (horizontally and downhill), and when an opening to the land surface (in this case, a vertical wall) is found, groundwater discharge can occur in significant amounts.
This photo shows the approximate location of maximum subsidence in the United States, identified by research efforts of Dr. Joseph F. Poland (pictured). The site is in the San Joaquin Valley southwest of Mendota, California. Signs on pole show approximate altitude of land surface in 1925, 1955, and 1977. The land surface subsided about 9 meters from 1925 to 1977 due to aquifer-system compaction.
In this case, excessive groundwater pumping allowed the upper soil layers to dry out and compress and compact, which is by far the single largest cause of subsidence. Soil compaction results in a reduction of the pore sizes between soil particles, resulting in essentially a permanent condition-rewetting of the underground soil and rock does not cause the land to go back up in altitude. This results in a lessening of the total storage capacity of the aquifer system. Here, the term groundwater mining is really true
Happy Greenlanders and tourists enjoy the unique experience of dipping in the hot springs while enjoying drifting icebergs floating by on Uunartoq Island at the far southern tip of Greenland. These hot springs provide visitors with a perfect bath temperatures of about 100°F. Unlike the hot springs of Iceland, the hot springs in Greenland are not due to volcanic activity. It appears that the water is heated by deep layers in the earth's crust rubbing against each other. I'm sure the worldwide club of "Viewed icebergs while sitting in hot springs" is very small.
Sinkholes-Cover collapse sinkholes can develop abruptly
Cover collapse sinkholes, such as this one in Winter Park, Florida (1981), may develop abruptly, possibly over a period of hours, and cause catastrophic damage. These type of sinkholes occur where the covering sediments contain a significant amount of clay. Over time, surface drainage, erosion, and deposition of sinkhole into a shallower bowl-shaped depression.
Land subsidence: Mexico City has many land-subsidence problems
Yes, the buildings in this picture of Mexico City, Mexico are indeed showing a wave pattern instead of a straight line from left to right. In fact, situations such as these are happening throughout Mexico City, where long-term extraction of groundwater has caused significant land subsidence and associated aquifer-system compaction, which has damaged colonial-era buildings, buckled highways, and disrupted water supply and waste-water drainage. Some buildings have been deemed unsafe and have been closed and many others have needed repairs to keep them intact.
Why is the ocean salty? Hydrothermal vents at the sea floor
The Mariana Arc is part of the Ring of Fire that lies to the north of Guam in the western Pacific. In 2004, scientists exploring the NW Eifuku volcano near the Mariana Islands reported seeing small white chimneys emitting a cloudy white fluid near the volcano's summit, as well as masses of bubbles rising from the sediment around the chimneys. In this picture you can see masses of minerals and carbon dioxide escaping from the earth's crust into the ocean. These vents contribute dissolved minerals to the oceans, which is one reason the oceans are salty.
This photo shows Silver Glen Springs in the Ocala National Forest, Florida. Florida has large numbers of springs due to the abundance of karst geology and porous limestone below the land surface. The spring pool at Silver Glen Springs is about 200 feet across. While it's only about 2 to 3 feet deep in many places, around the outflow hole the depth is about 18 feet. Typical of springs, the water is very clear and free of suspended and particulate matter, unlike water flowing in rivers and in lakes.
A collapse sinkhole in Guatemala City, Guatemala, 2010
This dramatic sinkhole formed in Guatemala City in June, 2010. Geologists are saying that the main cause is human activity, though. A burst sewer pipe or storm drain probably hollowed out the underground cavity that allowed the chasm to form, according to Sam Bonis, a geologist at Dartmouth College in New Hampshire. Also contributing is the fact that the top layer of earth the city is built on is fairly unconsolidated and loose, thus making it prone to movement and erosion. This sinkhole was estimated to be 60 feet (18 meters) wide and 300 feet (100 meters) deep.
The water flowing out of this cliff is groundwater discharging from the Eastern Snake River Plain aquifer from basalt cliffs above the Snake River Gorge, Idaho, USA. The water flows from fissures in a more-or-less horizontal and downward direction and results in springs when these water-bearing layers intersect the open hillside. Faults, fractures, and rock layers strongly influence the flow paths of groundwater.
Land subsidence: Fissures in the Mojave Desert, California
The withdrawal of groundwater near Lucerne Lake (dry) in San Bernardino County, Mojave Desert, California has caused the land to subside, with the results being the formation of fissures on the landscape. In some instances, the fissures were more than 1 meter (3.3 feet) wide and deep. Fissuring often is associated with localized differential compaction of sediments. The 5-gallon bucket can be used as a scale reference.
This picture is really just showing an open pipe stuck deep into the ground—a water well, in this case. What is unique about this well, in southern Georgia, USA, is that it taps an artesian aquifer, in which the water saturating the aquifer is under pressure from being confined between two fairly impermeable layers of rock (above and below). Just as with the air in a blown-up balloon rushing out when the opening is untied, when a well taps an artesian aquifer, the water is pushed up the well pipe. Now, depending on the internal pressure, the water may not reach the land surface, but, as this picture shows, if the pressure is high enough water can be pushed dozens of feet above the land surface ... no pump needed.