Thanks a lot

Thanks for your answer

Which of the following are important in the karst development?

1) Atmospheric precipitation (type[rain or snow] and amount of precipitation),

2) temperature,

3) Relief and local base level of erosion,

4)geological settings, tectonic settings and folds,

5) stratigraphic settings,

6) thickness and lithology of limestone formations adjacent formations

what do you think about these prioritize?

Dear William Sallun Filho

Thank you so much for your attention and your Answer

With best regards

Majid Dashti Barmaki

It is known that calcite has more solubility in water than dolomite, so the karstifcation will be more in calcite, but the crushed or powdered dolomite becomes more soluble than in its intact case......

Dear Abdullah, thanks a lot

In the area inside, and below Carlsbad Caverns is full of Gypsum.

The Permian Reef formed in a shallow marine environment in a very

long arc structure above a fracture that was releasing Hydrogen

Sulfide Gas. The Reef formed over this supply of nutrients for the

Corals.

At the end Of the Permian there was a sudden drop in ocean

elevation of 80 meters. The reef died, and the Hydrogen Sulfide

Gas then collected inside the reef along with stagnant water to

form a dilute sulfuric acid which attacked the reef, and the

layered structure of the Back reef. As the continent rose,

and or the water receded, the Gypsum that formed from the

limestone was removed by rainfall, and flow thru the enlarging

fractures and cave conduits.

The area is now elevated between 4,000 to over 8,000 feet

above sea level and about 4,000 feet to zero feet above the

top of the Gypsum Plains of Texas.

The highest exposed elevation is at El Capitan Texas,

and the reef goes underground when it reaches the

Pecos River at Carlsbad New Mexico.

It is interesting that Sulfuric acid makes the majority of the

Cave systems, while Carbonic acid is responsible for making

Stalactites, Stalagmites, and Columns.

In more Karstic areas, the flowing water of rivers flowing thru

the fractures in the limestone makes caves at the intersection

between vertical fractures, and more horizontal layers.

This would be typical of the 3D mazes of Horizontal Passages

in Mammoth Cave Kentucky that formed sequentially as the

Green River downcut thru the Limestone following the long term

downward trend in the Elevation of Ocean levels prior to

about 12,000 to 14,000 years ago.when ocean levels began to

rise again with the melting of the continental ice sheets.

It rose about 120 meters.

Calcium Carbonate and Magnesium Carbonate dissolve at

different rates, but the most soluble is Gypsum

( Calcium Sulfate ).

If I remember correctly Calcium Carbonate is more soluble than

Magnesium Carbonate.

For examples of various caves look at the GOOGLE Images

of Lechuguilla Cave, Carlsbad Caverns, Mammoth Cave,

Cave of the Winds, Wind Cave, Jewel Cave,

Snowy River-Ft Stanton Cave, and for a special treat,

Cave of the Crystals-Mexico.

Dear Michael

Thank you so much for your attention and your Answer.

1. "It is interesting that Sulfuric acid makes the majority of the Cave systems, while Carbonic acid is responsible for making Stalactites, Stalagmites, and Columns". Is there any reason for this? Perhaps the Sulfuric acid is more effective than Carbonic acid. Is that true?

2.How do you approach the process of dissolution of carbonate in the laboratory? In your opinion, how can the carbonate dissolution process was studied in the laboratory? How much time do we need to run this process?

I would set it up such that the acid drips on the block of limestone at a

known rate. You would need to test acid at different concentrations

simultaneously on a slab of limestone of a uniform thickness to

see how long each one takes to eat through the limestone slab.

In high vegetation areas like South east Asia, it could be Humic Acid.

The sulfuric acid had many million of years to make the caves

while the reefs were still under water.

The Carbonic Acid would be active when the cave were exposed to

the CO2 in the Air. The Rainwater dissolves the limestone in one

location, and it is redeposited thru evaporation of water off the

surface of the cave formations.

An interesting formation is when a false floor forms on

the surface of a cave lake. the inflow is one drop of water at a time.

The outflow is evaporation of water during barometric pressure changes.

For thousand to hundreds of thousands of years the process keeps the

lake at the same elevation. The false floors grow outward from the walls

at 5,000 years to and inch, or much less if the perimeter of the lake is

long. So it can take 10's of thousands of years for a false floor to

grow and cover over a lake.

The thickness of the floor is always the same at bout 4 inches thick

( 100 mm ).

now thing about the amount of minerals in solution in one drop of

water, and think about how many drops of water it takes in

100,000 years to grow a false floor over the surface of a cave lake.

One drop of water may take several minutes to form and to fall.

The volume of the water that drips, and evaporates is vastly greater

than the total amount of minerals that form up the volume of one

false floor on one lake.

Calcite is more soluble that dolomite. A limestone-dolomite rock may become porous. In dolomitie places karrens are smooth (looking like elephant skin ) while they are sharpen in pure limestone zones. Erosion in dolomitic karsts produces sand that fills in the sinkholes and the caves. The mixing between dolomite sand and clay produces a sediment that may partially block the ground water circulations

It is true that dolomite is less soluble than calcite, and the majority of the world's caves are on (calcite) limestone.

   However, one should not take that as a ruling factor. There are plenty of extensive caves in dolomite (reference 1 below). So do not reject the potential of any area just because it is dolomite (or dolostone as the purists now insist on calling the rock made of dolomite mineral).

   Also be cautious of reports of a rock being "dolomite" as identification is not easy in the field. The 120km Bullita Cave was originally reported as being in "dolomite" (see reference 2 below) but when Jaques Martini looked closer he found that it was actually in a thinly interbedded dolomite and limestone (see Fig 7).

   Eric Gilli's comment on sand is relevant at Bullita in that the initial surface solution in the karrenfield dissolves the calcite but leaves the dolomite grains which wash down into the cave, where they DO however dissolve eventually in the wet season floodwaters. Also at Bullita, we found that there are extensive areas of a secondary (diagenetic) dolomitisation event that produces a coarser grained, totally dolomitic, rock that forms very little karst. It breaks down quickly to dolomite sand, and the important factor there seems to be the grain size rather than the composition.

Check the following two papers at my RG profile...

1: Webb, Grimes & Osborne, 2003: "Caves in the Australian Landscape" gives an overview - search in it for "dolomite" for examples of dolomite caves in Australia.

2: Martini & Grimes 2012: "Epikarstic maze cave development: Bullita Cave..." This is formed in thinly interbedded dolomite & limestone. See also Jaques' detailed discussion of dolomite weathering.