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The Formation is associated with deposits of the Chalk Group, subsequent Palaeogene and Neogene strata, and occasionally Upper Greensand. [2] It occurs in sheets or patches of various sizes over a large area in the south of England, from Hertfordshire on the north to Sussex on the south, and from Kent on the east to Devon on the west.
Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, [1] [2] categorized as the variety of chert that occurs in chalk or marly limestone. Historically, flint was widely used to make stone tools and start fires. Flint occurs chiefly as nodules and masses in sedimentary rocks, such as chalks and limestones.
The Gunflint Iron Formation is a banded iron formation, composed predominantly of dense chert and slate layers interbedded with ankerite carbonate layers. The chert layers can be subdivided into black layers (containing organic material and pyrite), red layers (containing hematite), and green layers (containing siderite). [5]
Upper Mercer flint or Upper Mercer chert is a type of flint, or a pure form of chert, found in Coshocton, Hocking, and Perry counties of Ohio. Made of forms of silica and quartz , the hard and brittle stone was used by prehistoric people to make tools and weapons.
Vaqueros Formation sandstone with concretions A mosaic of images showing spherules, some partly embedded, spread over (smaller) soil grains on the Martian surface. Concretions are found in a variety of rocks, but are particularly common in shales, siltstones, and sandstones. [30]
Depending on its physical characteristics, a number of different names, such as underclay, fireclay, flint clay, and ganister, can be applied to a specific seatearth. Underclay [ edit ]
Another example of the use of spectral gamma ray logs is to identify specific clay types, like kaolinite or illite. This may be useful for interpreting the environment of deposition as kaolinite can form from feldspars in tropical soils by leaching of potassium; and low potassium readings may thus indicate the presence of one or more paleosols. [2]
The route to the southern end of the flint fields is a well maintained and picturesque woodland path which branches off the old B 196a federal road immediately north of the caravan park (former traffic testing area). The nearest railway stop is Prora, around 2½ kilometres south of the area and five hundred metres south of the traffic testing area.