https://bereket-haileab.geology.sites.carleton.edu/files/original/1f7da46df03dc16adf630242260a769f.jpg 88492f949c9673694da4de0b93da2a74 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Sedimentary Rocks Subject The topic of the resource This collection includes sandstones, limestones, breccias, conglomerates, dolostones, shales, oolites, and BIF. Creator An entity primarily responsible for making the resource Bereket Haileab Source A related resource from which the described resource is derived Housed in Anderson Hall, Carleton College. Format The file format, physical medium, or dimensions of the resource Thin sections, thin section scans, hand samples, hand sample images, photomicrographs. Thin section Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource BH250-175g Subject The topic of the resource Tapeats Sandstone Description An account of the resource Major Minerals: quartz, feldspar Sandstone is one of the most common sedimentary rocks and plays a critical role in sedimentary geology, stratigraphy, petroleum geology, and hydrogeology. It is a clastic sedimentary rock composed primarily of sand-sized particles (0.0625 to 2 mm in diameter), cemented together by a matrix of finer particles and/or chemical cement. The most abundant mineral in sandstone is quartz, valued for its hardness and chemical stability. Feldspars—both plagioclase and K-feldspar—are also common, particularly in arkosic sandstones, although they are less chemically stable than quartz. Sandstones often contain lithic fragments, which are pieces of pre-existing igneous, metamorphic, or sedimentary rocks. Accessory minerals may include micas (muscovite and biotite), zircon, tourmaline, magnetite, and garnet. The mineralogical composition of sandstone provides essential clues about its provenance. Provenance analysis is a powerful tool in reconstructing sediment transport pathways and inferring tectonic settings. Cementation and Diagenesis: Cementation is a diagenetic process whereby minerals precipitate in the pore spaces between grains, binding them together. Common types of cement include: Silica (cryptocrystalline silica/quartz overgrowths) Calcite (CaCO₃) Iron oxides (e.g., hematite, goethite) Clay minerals, such as Fe-rich illite (glauconite) Sandstone Classification Sandstones are classified based on grain composition and matrix content: By Grain Composition (QFL: Quartz–Feldspar–Lithic Fragments): Quartz arenite: >90% quartz Arkose (feldspathic arenite): >25% feldspar Litharenite: >25% lithic fragments By Matrix Content: Arenite: Clean sandstone with <15% matrix Wacke: Mud-rich sandstone with >15% matrix (e.g., graywacke) Depositional Environments Sandstones form in a range of depositional environments, including: Fluvial Aeolian Shoreline/Beach Deltaic Deep-marine (e.g., turbidites) BH250 Sandstone Collection The BH250 collection includes thirteen sandstone samples collected from southeastern Minnesota and from geology field trips across the Midwest, South Dakota, the Grand Canyon, and Death Valley. Each sample is accompanied by hand specimens, thin sections, and photomicrographs, providing an excellent foundation for detailed petrographic analysis. Here you will find short descriptions for each sandstone sample. BH250-175g is sample collected from Grand Canyon which is the Tapeats Sandstone. The Tapeats Sandstone is the basal Cambrian sedimentary unit of the Tonto Group in the Grand Canyon and serves as a key marker for understanding the Cambrian Explosion and the Great Cambrian Transgression across North America. It is a quartz-rich sandstone, ranging from arkosic to subarkosic compositions, with a conglomeratic base in some areas. The grain size is coarse at the base, often appearing as pebbly conglomerate, and gradually fines upward to medium or fine sandstone. Th cement in this sandstone is primarily silica or iron oxide. The Tapeats Sandstone correlates with several Cambrian sandstones across North America, including the Mount Simon Sandstone of the Midwest (Illinois, Wisconsin, Minnesota). Coverage The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant Location: Mile 222 Campground, Grand Canyon, Arizona, USA Nearby Geographic Feature: Grand Canyon GPS Coordinates: 35.80535, -113.332917 Date A point or period of time associated with an event in the lifecycle of the resource August 2021 Source A related resource from which the described resource is derived From the rock collection of Bereket Haileab. Sample BH250-175g. Housed at Carleton College in Minnesota. Type The nature or genre of the resource Thin section Relation A related resource <iframe width="100%" height="600" style="border: 0;" src="https://carleton.maps.arcgis.com/apps/instant/media/index.html?appid=a58a2b9a1ca34fdaa4e5e3d9f39a161a" frameborder="0" allowfullscreen="allowfullscreen">iFrames are not supported on this page.</iframe><br />View on ArcGIS Online <a href="https://carleton.maps.arcgis.com/home/item.html?id=a58a2b9a1ca34fdaa4e5e3d9f39a161a">here</a><br /><br /><iframe width="100%" height="480" src="https://drive.google.com/file/d/10KlOBM75e68XBEurGlIjUXYfj62kN_0W/preview" allow="autoplay"></iframe><br /><br /><iframe width="100%" height="480" src="https://drive.google.com/file/d/11hyxqCVGiyeQLLgB1d76k0iiY8VDBgt7/preview" allow="autoplay"></iframe><br /><br /><iframe width="100%" height="480" src="https://drive.google.com/file/d/1dKm10Cqyxk7fPWbC0IUXT9bUtyT66rrz/preview" allow="autoplay"></iframe><br /><br /><iframe width="100%" height="480" src="https://drive.google.com/file/d/1b1OcJ_eTWI2qVVAT6A5KmmROTcx5JAK5/preview" allow="autoplay"></iframe><br /><br /><iframe width="100%" height="480" src="https://drive.google.com/file/d/1dpSiS_uVvRlOJY0FphPJ23T77mzXlVKC/preview" allow="autoplay"></iframe><br /><br /><iframe width="100%" height="480" src="https://drive.google.com/file/d/1xuy2ldRf2IEgHgmJ4UIliIkDvNnKZK-E/preview" allow="autoplay"></iframe><iframe width="100%" height="480" src="https://drive.google.com/file/d/1gld_jV6qgDG0nLz7FMwq7Nvlb8u1WzlO/preview" allow="autoplay"></iframe> Creator An entity primarily responsible for making the resource Bereket Haileab Arkosic Sandstone Basal Cambrian unit Cambrian Sandstone Clastic sedimentary rock Feldspar Grand Canyon Geology Great Cambrian Transgression Iron oxide cement Mile 222 Campground Mount Simon Sandstone Equivalent Quartz Quartz-rich Quartz-rich Sandstone sandstone sedimentary Silica cement siliciclastic Subarkosic Sandstone Tapeats Sandstone Tonto Group