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The Kalkberg Formation
The Kalkberg Formation, part of the Helderberg Group, was deposited during the Early Devonian. Exposures of the Kalkberg Formation are found west and south of Albany, New York. The Helderberg Group also includes the Alsen, New Scotland, Coeymans, Port Ewen and Manlius Formations. The Kalkberg Formation is 15 meters to 30 meters thick; The Heldberg Group overall is 135 meters thick. The primary rock type of the Kalkberg Formation is a medium-dark-gray limestone rich in clay and silica.

The Kalkberg Formation is very well exposed near the village of Catskill, Greene County, New York. "Kalkberg" means limestone mountain and this formation obtained its name from the local Dutch name for Helderberg ridge.

Lithology/Stratigraphy
The Kalkberg Formation is a fine grained, chert bearing, argillaceous limestone interbedded with calcareous shale. The Kalkberg Formation overlies the Coeymans Formation and underlies the New Scotland Formation. These three formations are apart of the Helderberg Group. The difference between these three units is that the Coeymans Formation is a bioclastic packstone that has well defined coarser grained rock and interbedded shale units, representing an off shelf limestone with chert deposits. The primary rock type of the New Scotland Formation is a limestone of fine to medium grained sediments containing clay. The New Scotland Formation has an abundance of marine faunas, especially bottom dwellers. The appearance of chert at the base of the Kalkberg Formation as well as the existence of chert nodules and sparry calcite distinguish this limestone unit from the Coeymans Formation. The regular thin to medium bedding of the Kalkberg Formation may be due to bioturbation.

Depositional Setting/Tectonics
The Kalkberg Formation was deposited during a marine transgression in the Lower Devonian and represents a middle shelf, open marine environment which developed on a shelf seaward of the Coeymans Formation. The deepening of the sea resulted in the deposition of calcareous limestone along the eastern edge of the Appalachian Basin, now preserved in the Kalkberg Formation. The warm seas were favorable to an array of marine fauna including solitary and colonial corals. Thick stems of the crinoid, Maracrinus stoloniferus, and the brachiopod species Bilobites varicus characterize the lower beds of the Kalkberg Formation. Additional organisms that thrived in this stable environment and are preserved within the Kalkberg Formation include bryozoans, brachiopods, crinoids, corals, mollusks, ostracodes, and trilobites.

This concludes that the depositional setting of the Kalkberg Formation was not near a highland area because the sediment facies represented in the unit does not include sand or gravel grains. The Acadian Orogeny occurred during the Middle Devonian and was one of three mountain building events that created the Appalachian mountain chain. The Acadian Orogeny tilted the Kalkberg Formation from its original position due to the collision of the North American plate with Avalonia. .

Please refer to this link: Figure 8.5: Image of different facies of Helderberg Group. This image shows the depositional environments for the different formations of the Helderberg Group are represented.