dolomitisation BrE
dolomitization AmE

It presents a good example of the geological phenomenon of dolomitisation.

Dolomitisation can occur in both members.

In comparison, lower K4 has more fabric-selective pores that have been connected by fabric retentive to selective dolomitisation.

These brines percolated downwards, causing dolomitisation and leaving the pre-existing texture and porosity of the sediments largely unchanged.

While dolomitisation enhanced reservoir properties in the upper K2 and lower K4 units, lower part of K2 and upper part of K4 have experienced more dissolution.

Though both upper K2 and lower K4 are dolomitised, in upper K2 unit non-fabric selective pores are dominant and fabric destructive dolomitisation is the main cause of high reservoir quality.

In the Jura the Tithonian can be seen in places to be a coral reef limestone, but usually the corals have been obliterated by dolomitisation and dedolomitisation as is commonly the fate of reefs.

The quarry exhibits pale to dark grey Carboniferous Limestone with small area of overlying horizontally bedded buff-coloured Jurassic oolitic limestone forming an angular unconformity, with extensive dolomitisation of top of the Black Rock Limestone.

The specific mechanism of dolomitization, involving sulfate-reducing bacteria, has not yet been demonstrated.

Coral atolls are also an important place where dolomitization of calcite occurs.

One common form of large-scale replacement in carbonate sediments is dolomitization (Fig. 5.40c, d).

These intertidal sediments experienced a strong contemporaneous dolomitization.

Porosity usually decreases during diagenesis, except in rare cases such as dissolution of minerals and dolomitization.

Caymanite deposition predated dolomitization, a process where limestone is altered from contact with magnesium-rich water.

Dolomitization involves substantial amount of recrystallization.

He made many contributions to the geological knowledge of the Irati formation, including the dolomitization process of carbonate rocks.

Environments with high temperatures (about 50 C) like subsurface and hydrothermal environments are conducive to dolomitization.

Dolomitization in the Bluff Formations of Cayman Brac occurred 2-5 million years ago.

The Albian, 105-100 Ma, Zonguldak Formation is predominantly limestone with areas of dolomitization.

In Ohio, where the unit has escaped dolomitization, the Brassfield is an encrinite biosparite with numerous crinoid species.

This suggests the alteration and replacement of limestone sediments by dolomitization in ancient rocks was possibly aided by ancestors to these anaerobic bacteria.

Dolomitization is a process by which dolomite is formed when magnesium ions replace calcium ions in calcite.

The dolomite and limestone within the Bass formation have been affected by post-depositional alteration including: dolomitization, recrystallization, stylolitization, and silicification.

Dolomitization of calcite also occurs at certain depths of coral atolls where water is undersaturated in calcium carbonate but saturated in dolomite.

If the kinetic inhibitors and high temperatures are compatible then dolomitization can take place in saline environments above thermodynamic and kinetic saturation with respect to dolomite.

The 100 to 150 m thick Upper Oxfordian is represented west of the oolite barrier by intratidal platform sediments (argillaceous to sandy, pyrite-bearing limestones), whereas, in the east, dolomitization continues.

Because, during dolomitization, traces of fossils are largely lost as a result of recrystallization, fossils in Wetterstein dolomite are harder to distinguish, and even in thin sections may be barely recognizable.

When requirements are fulfilled dolomitization can take place in alkaline environments which are those under the influence of bacterial reduction and fermentation processes, and areas with high input alkaline continental groundwaters.

They are commonly alteration products of the primary detrital grains, but may also form from the introduction of additional ions by circulating pore fluids, as in many instances of dolomitization of a precursor carbonate.

Other diagenetic features such as corrosion of quartz grains by carbonate, relative timing of quartz overgrowth formation and cementation and the onset of dolomitization can also be rapidly documented with CL.

Dolomitization depends on specific conditions which include low Ca:Mg ratio in solution, reactant surface area, the mineralogy of the reactant, high temperatures which represents the thermodynamic stability of the system, and the presence of kinetic inhibitors like sulfate.

He did his Ph.D. at the University of Newcastle-upon-Tyne from 1968 to 1972, working on the sedimentology and dolomitization of the limestone member of the Carboniferous Middle Limestone Group of Northumberland, northeast England.

Secondary dolomitization of limestone is common, where calcite or aragonite are converted to dolomite; this reaction increases pore space (the unit cell volume of dolomite is 88% that of calcite), which can create a reservoir for oil and gas.