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The Cardenas Basalt, also known as either the Cardenas Lava or Cardenas Lavas, is a rock formation that outcrops over an area of about 310 km 2 (120 mi 2) in the eastern Grand Canyon, Coconino County, Arizona.
Stromatolites have been reported from the Comanche Point Member. The Dox Formation locally interfingers with, and is baked by, basalt lava flows of the overlying Cardenas Basalt. Within the central Grand Canyon, pre-Tapeats Sandstone erosion has removed parts of the Unkar Group above the level of the middle part of the Dox Formation.
The Uinkaret volcanic field is an area of monogenetic volcanoes in northwestern Arizona, United States, located on the north rim of the Grand Canyon. [2] Lava flows from the Uinkaret volcanic field that have cascaded down into the Grand Canyon, damming the Colorado River, have been used to date the canyon's carving. [3]
The Neoproterozoic Nankoweap Formation (pronounced Nan' coe weep), is a thin sequence of distinctive red beds that consist of reddish brown and tan sandstones and subordinate siltstones and mudrocks that unconformably overlie basaltic lava flows of the Cardenas Basalt of the Unkar Group and underlie the sedimentary strata of the Galeros Formation of the Chuar Group.
Dolomite and limestone dominate the Bass Formation in the central part of the Grand Canyon, while the sandstone, conglomerate, and argillite dominate the Bass Formation in the eastern part of the Grand Canyon. The Bass Formation typically becomes generally finer grained toward the top. [2] [5] [6] [7] Volcanic ash layers occur in the Bass ...
The Apache Group near the bottom of the Grand Canyon, includes fluvial shale and sandstone, as well as limestone from a shallow sea, exposed in the Salt River Canyon. The limestone contains stromatolite remains, mounds of blue-green algae. The Apache Group was intruded with basalt and diabase between 1.05 and 1.14
Basalt columns seen on Porto Santo Island, Portugal. Columnar jointing of volcanic rocks exists in many places on Earth. Perhaps the most famous basalt lava flow in the world is the Giant's Causeway in Northern Ireland, in which the vertical joints form polygonal columns and give the impression of having been artificially constructed.
The Columbia River Basalt Group (including the Steen and Picture Gorge basalts) extends over portions of four states. The Columbia River Basalt Group (CRBG) is the youngest, smallest and one of the best-preserved continental flood basalt provinces on Earth, covering over 210,000 km 2 (81,000 sq mi) mainly eastern Oregon and Washington, western Idaho, and part of northern Nevada. [1]