Search results
Results from the WOW.Com Content Network
Dolomite (also known as dolomite rock, dolostone or dolomitic rock) is a sedimentary carbonate rock that contains a high percentage of the mineral dolomite, CaMg(CO 3) 2. It occurs widely, often in association with limestone and evaporites , though it is less abundant than limestone and rare in Cenozoic rock beds (beds less than about 66 ...
Vast deposits of dolomite are present in the geological record, but the mineral is relatively rare in modern environments. Reproducible, inorganic low-temperature syntheses of dolomite are yet to be performed. Usually, the initial inorganic precipitation of a metastable "precursor" (such as magnesium calcite) can easily be achieved.
Dolomitization is a geological process by which the carbonate mineral dolomite is formed when magnesium ions replace calcium ions in another carbonate mineral, calcite. It is common for this mineral alteration into dolomite to take place due to evaporation of water in the sabkha area. [1] Dolomitization involves substantial amount of ...
Limestone is the most common carbonate rock [3] and is a sedimentary rock made of calcium carbonate with two main polymorphs: calcite and aragonite.While the chemical composition of these two minerals is the same, their physical properties differ significantly due to their different crystalline form.
Based on the Köppen climate classification, Dolomite Peak is located in a subarctic climate with cold, snowy winters, and mild summers. [7] Temperatures can drop below −20 °C with wind chill factors below −30 °C. Precipitation runoff from Dolomite Peak drains into the Bow River which is a tributary of the Saskatchewan River. The months ...
Cap carbonates are found on most continents. [4] They are typically 3–30 meters thick, laminated structures. They are depleted in 13 C compared to other carbonates. The progression of late Neoproterozoic glaciations portrayed by substantial δ 13 C deviations in cap carbonates suggest out of control ice albedo.
Modern dolomite is quite rare. There is evidence that, while the modern ocean favors precipitation of aragonite, the oceans of the Paleozoic and middle to late Cenozoic favored precipitation of calcite. This may indicate a lower Mg/Ca ratio in the ocean water of those times. [61]
McKenzie's work on the 'dolomite problem', an enigma whereby the past prevalence of dolomite is higher than what is found in modern environments, [19] has recently revealed that dolomite is precipitated by bacteria living under anoxic conditions which was first observed in the laboratory with sulfate-reducing Desulfovibrio, [20] and ...