Greywacke - Wikipedia
Greywacke or graywacke (German grauwacke, signifying a grey, earthy rock) is a variety of sandstone generally characterized by its hardness (6–7 on Mohs scale), dark color, and poorly sorted angular grains of quartz, feldspar, and small rock fragments or sand-size lithic fragments set in a compact, clay-fine matrix.
Greywacke Rock | Properties, Formation, Uses - Geology Science
2023年4月23日 · If the rock has between 10 and 50% clay matrix, the rock is called a wacke. Quartz wackes have predominantly quartz surrounded by a mud or clay matrix. In a feldspathic wacke, feldspar is more abundant, and in a lithic wacke, lithic fragments are more abundant.
Sedimentary rock - Wackes, Stratification, Deposition | Britannica
2024年12月20日 · Sedimentary rock - Wackes, Stratification, Deposition: Wacke, or graywacke, is the name applied to generally dark-coloured, very strongly bonded sandstones that consist of a heterogeneous mixture of rock fragments, feldspar, and quartz of sand size, together with appreciable amounts of mud matrix.
9.1 Clastic Sedimentary Rocks – Physical Geology – H5P Edition
Wacke is a “dirty” sandstone, containing 15-75% fine-grained particles (clay, silt) in its matrix. A wacke can have more fine-grained particles than cement in its matrix, making for a crumbly rock. Wackes are subdivided in the same way that arenites …
Sedimentary rock - Clastic, Chemical, Organic | Britannica
2024年12月20日 · This classification scheme also recognizes three major types of wackes or graywackes that are roughly analogous with the three major arenite groups: quartz wacke, feldspathic wacke (with the subvariety arkosic wacke), and lithic wacke. The three major arenite sandstone families are separately described below, but the varieties of wacke can be ...
9.1 Clastic Sedimentary Rocks - University of Saskatchewan
A wacke can have more fine-grained particles than cement in its matrix, making for a crumbly rock. Wackes are subdivided in the same way that arenites are: quartz wacke, feldspathic wacke, and lithic wacke. Another name for a lithic wacke is greywacke.
6.1: Clastic Sedimentary Rocks - Geosciences LibreTexts
2024年4月24日 · A sandstone with more than 15% silt or clay is called a wacke (pronounced wackie). The terms quartz wacke, lithic wacke, and feldspathic wacke are used with limits similar to those on the arenite diagram. Another name for a lithic wacke is greywacke. Some examples of sandstones, magnified in thin section are shown in Figure \(\PageIndex{7}\).
Lithic wacke sandstone - James Madison University
2000年7月18日 · Lithic wacke sandstones, especially those containing feldspar are associated with regions of great tectonic activity. This specimen was eroded from a volcanic arc system that collided with eastern North America during the Taconic orogeny .
Lithic-wacke: Mineral information, data and localities. - mindat.org
Lithic-wacke: Mineral information, data and localities. This page is currently not sponsored. Click here to sponsor this page. A wacke where at least 5% of the interstitial material is rock fragments, and rock fragments>feldspar, with the remainder being quartz. Wackes according to composition (after Pettijohn et al. 1987)
Wacke | Clastic, Sedimentary & Igneous | Britannica
Wacke, sedimentary rock composed of sand-sized grains (0.063–2 mm [0.0025–0.078 inch]) with a fine-grained clay matrix. The sand-sized grains are frequently composed of rock fragments of wide-ranging mineralogies (e.g., those consisting of …