Speleotheme/staglimites karst?

Question

do Speleotheme and staglimites form because of karst. b/c acidic rain get into the cracks of carbonic rock and drips down into caves.

Answer 1

Cave Formations
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Cave Formations

Cave formations are deposits on the ceiling, floor, and walls of a cave. They are called speleothems.The creation or these formations depends upon the following: (1) the amount of surface water entering the ground abpve the cave, (2) the type of rocks in and around the cave, (3) the dissolved materials contained in the water as it enters the cave, and (4) the cave environment -- amount of moisture in the air, amount of air flow through the cave, and the cave terperature. Most caves have enough openings to allow air movement, which does evaporate some of the moisture and causes the precipitation of calcite and aragonite from the seeping waters. Nature creates formations in a cave very slowly. It may take one hundred to one hundred fifty years to form an inch of material to the speleothems. These speleothems may take the form of icicles, trees, statues, or the delicate design of lacy flowers. The coloration of these structures varies from white or cream, to yellowish or dark brown which is due to the presence of limonite that is dissolved from the overlaying rocks. The red and orange hue comes from dissolved iron mixing with water to form iron oxide. The blue is derived from manganese. "Cave onyx" is made up of a variety of calcite. It has a banded, rich brown appearance. Speleothems that are white are almost pure calcite. The color variations and the configurations of the cave’s gradual deposits create the beautiful wonderland of this under explored area of our earth.

Stalactites

Stalactites are the formations that form on the ceilings of caves whichmvc-015f.jpg (53775 bytes) look like icicles. To remember their location, think of holding on "tite" to a ceiling. One could, also, remember that the word stalactite has the letter ‘c’ which could represent the ceiling. They begin their life as a single drop of water which has been combined with carbon dioxide, calcium carbonate, and calcite. The water drop is squeezed from between the rocks and drops to the floor leaving behind a minute deposit of the dissolved calcite in the shape of a ring. Ring forms upon ring until a small drop like tube hangs from the ceiling called a "soda straw." Through the loss of the carbon dioxide process the dissolved calcite deposit continues until beautiful stalactites are formed.

Stalagmites

Stalagmites are the formations found on the floor of caves, reachingmvc-021f.jpg (44458 bytes) upward to touch the stalacites hanging from the ceiling. In order to remember the stalagmite, think of "mite or mighty" coming from the floor. Another way would be to remember the word stalagmite had a ‘g’ which could stand for ground. For every drop of water that enters and falls in a cave a formation is found. Stalagmites are the result of the excess water dropping from its parent, the stalactite. A stalagmite is more rounded, smoother, and has no central tube as the stalactite does. Straight formations of stalagmites are called "broomsticks." If the cave ceiling is very high the water droplet will splatter over a larger area, a stubby, flat formation will occur that may resemble a stack of "pancakes."

Columns

Columns are formed when the stalactite and the stalagmite continue to build and grow. When the two join, they form a single pillar or column reaching from the floor to the ceiling.



Helictites

Helictites are a mystery to scientists. They do not know why these formations are so turned and twisted. Helictites formations defy nature, and gravity. They turn and twist into irregular forms like tree roots seeking a water source. Scientist have hypothesized that they may be the result of water being forced through tiny openings in the ceilings, walls, or floor.They may, also, be the results of wind currents or earth tremors. A helictite starts its growth as a tiny stalactite. For an unknown reason the chemical composition of the water is slightly altered causing the single crystal structure to change from a cylindrical shape to a conical one. Sometimes each crystal fits into the prior one like an inverted stack of ice cream cones. The direction of the end of the straw may wander, twist like a corkscrew, or the main part may form normally while small helictites pop out of its side like rootlets or fishhooks. In some caves, helictites cluster together and form bushes as large as six feet tall. These bushes grow from the floor of the cave. They may form when water seeps into the cave through pores so small that the flow is controlled by capillary action and not gravity. The helictites are, perhaps, the most delicate and most beautiful of the cave formations.

Rimstone Pools

The humidity level in caves is very high. Water in caves without a flow of air, generally does notpool.jpg (31811 bytes) evaporate. The excess water flowing from the surface area is collected in small underground pools. Naturally the collected water is rich in mineral deposits. Any sort of disturbance of these pools results in collections of calcite around the rim, which are called stalagmite ridges with horizontal crests. These crests act like small dams that hold back the pools of water. These dams are referred to as rimstone pools. Continued growth of these rimstone pools tend to reinforce the cave against collapse.

Shields

Round and flat formations are known as shields. They are disk-shaped layers of calcite from the wall and ceilings. A cutaway section of a shield would reveal two flat disks sandwiched together. Water flows between these two plates and stalactites begin to form along the edge. Scientist do not know why they have not cemented themselves together. Nor how they can form different angles to the bedding and joints of the other limestone formations. They are found only in certain caves. Some have reached a diameter of ten feet. It is thought that hydrostatic pressure and slight earth movements play a part in their growth.

Gypsum Flower

Gypsum is a mineral containing both calcium and sulfur. Gypsum will form in the dry areas of the cave walls or floors. It makes a crust that sparkles in the lamp light. They appear to extend from the wall. They are twisted and curled projections that do not require support. They are about ten to twelve inches in length. They are very fragile and fall from their own weight. The Indians harvested gypsum so it could be used as paint for their faces and body as well as medical purposes.

Anthodites

Anthodites have a delicate, fragile appearance. Many times anthodites are referred to as stone flowers, perhaps, because their hairlike crystals have a central point of formation. Found on the walls or ceilings, anthodites is composed of calcium carbonate. However, the calcium carbonate in this formation is in a different crystal form, called aragonite. It is this different growth behavior that gives anthodites their unique shape.

Selenite Needles

Selenite needles appear to form from a seed crystals on the floor of a cave. They are not attached to anything and occur in loose piles like jackstraws. They appear in the same areas as the gypsum flowers.

Boxwork

Fractures were made during the formation of the mountains. Continued pressure bent, twisted, and warped the limestone beds. Such pressure may create checkerboard-like layers, porous enough for water to stand in or flow through. All of these joints fill with the calcite as water flows over and through these fractures. Thus, boxwork is created. There will be no more growth because of the complete filling and cementing of the cracks. Boxwork projects from the walls or ceilings, forming a pattern much like that of honeycomb. The sides intersect each other at different angles forming "boxes" on the surface areas. Some of these ribbon- like structures are translucent.

Cave Pearls

Cave pearls are rare. They appear as water worn pebbles in a small pools of water. Their technicalpearls.jpg (14044 bytes) name is "cotiers." They are formed when a small deposit of calcite lodges around a small grain of sand or mi

Answer 2

UM Rolla is a robust place to seek for a karst geologist. yet another good source would be to objective an information superhighway seek for "cave grotto". the seek would desire to bring about different communities of cavers, some having contributors who're geologist who would desire to be very familiar with karst geology. additionally, check out the NSS, a countrywide team of human beings interested in caves. i'm helpful there are various sources at their website on the subject of karst.

Answer 3

yes and no. it doesn't have to be acidic rain, any water can do it. it breaks down the minerals and when they harden up (dry up) again, they form the cave formations. Water breaks down the CaCO2 in the rocks (calcium carbonate, found in karst - limestone - landscapes).

Hope that was easy to understand. And...notice how i didn't copy mine from another page.