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La Reforma (caldera)
La Reforma is a Plio-Pleistocene caldera on the Baja California Peninsula in Mexico. It is part of eleven volcanoes in Baja California, which formed with the Gulf of California during the Miocene, about ten million years ago. Previously, a volcanic arc had existed on the peninsula. The caldera's basement consists of granites and monzonites, formed between the Cretaceous and the Middle Miocene. The caldera has a diameter of and is surrounded by a rim high; its highest point is high above sea level. The formation of the caldera was accompanied by the eruption of a ignimbrite. After the eruption, volcanic activity continued in and around the caldera, forming lava domes, lava flows and a resurgent dome that rises above the caldera margin. Other volcanoes in the area include El Aguajito and Tres Virgenes. Geography and structure La Reforma is located in the municipality Mulegé, in east-central Baja California, Mexico, just south of the frontier between the departments ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baja California Sur
Baja California Sur, officially the Free and Sovereign State of Baja California Sur, is a state in Mexico. It is the 31st and last state to be admitted, in 1974. It is also the second least populated Mexican state and the ninth-largest state by area. Before becoming a state on 8 October 1974, the area was known as the ''El Territorio Sur de Baja California'' ("South Territory of Lower California"). It has an area of , or 3.57% of the land mass of Mexico, and occupies the southern half of the Baja California Peninsula, south of the 28th parallel north, 28th parallel, plus the uninhabited Rocas Alijos in the Pacific Ocean. It is bordered to the north by the state of Baja California, to the west by the Pacific Ocean, and to the east by the Gulf of California. The state has maritime borders with Sonora and Sinaloa to the east, across the Gulf of California. The state is home to the tourist resorts of Cabo San Lucas and San José del Cabo. Its largest city and capital is La Paz, Baja ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aguajito
El Aguajito (also called Santa Ana caldera) is a caldera volcano located on the Gulf of California in Mexico. It is located between the Tres Virgenes volcano and the La Reforma In History of Mexico, the history of Mexico, (from Spanish language, Spanish: "The Reform"), or reform laws, refers to a pivotal set of laws, including a Federal Constitution of the United Mexican States of 1857, new constitution, that were ... caldera. References Landforms of Baja California Sur Mountains of Mexico Calderas of Mexico Gulf of California Volcanoes of Baja California Sur Pleistocene calderas {{volcanology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Quintín Volcanic Field
The San Quintín Volcanic Field is a collection of ten or eleven volcanic cinder cones situated along the Pacific coast of the Baja California peninsula in Mexico. The field formed by repeated eruptions beginning in the Pleistocene and ending about 3000 years ago.Gorsline, D. S. and R. A. Stewart, Benthic marine exploration of Bahía de San Quintín, Baja California, 1960-61. Marine and Quaternary geology. ''Pac. Nat., 3'', 282-319, 1962.Woodford, A. O.The San Quintín volcanic field, lower California '' American Journal of Science'' 15:337-345, 1928. It is one of several known Quaternary period volcanic fields in Baja. The lava shields appear to have first grown as subaqueous volcanoes that emerged as islands.Luhr, J. F., Aranda-Gómez, J. J., and Housh, T. B. San Quintín Volcanic Field, Baja California Norte, México: Geology, petrology, and geochemistry. ''Journal of Geophysical Research'' 100:10353–10380, 1995. Currently located in a shallow bay, the cones are found in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinacate Peaks
The Pinacate Peaks (Sierra Pinacate, ) are a volcanic group, group of volcanic peaks and cinder cones located mostly in the Mexican state of Sonora along the international border adjacent to the U.S. state of Arizona, surrounded by the vast sand dune field of the Gran Desierto de Altar, at the desert's southeast. The Spanish name for the ''Pinacate Peaks'' geographic feature is the Sierra Pinacate, which is used in their homeland of Mexico. Location The Pinacate Peaks lie just north of the fishing resort of Puerto Peñasco. The tallest of the peaks is Cerro del Pinacate (also called Volcan Santa Clara), with an elevation of 3,904 feet (1,190 m). The Mexican Spanish word ''pinacate'' is derived from the Nahuatl word for the endemic desert pinacate beetle, stink beetle, ''pinacatl''. Natural History Geology The volcanoes here have erupted sporadically since about 4 million years ago, probably in association with the opening of the Gulf of California. The most rec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerro Prieto
Cerro Prieto () is a volcano located approximately 29 km (18 mi) SSE of Mexicali in the Mexican state of Baja California. The volcano lies astride a spreading center associated with the East Pacific Rise. This spreading center is also responsible for a large geothermal field, which has been harnessed to generate electric power by the Cerro Prieto Geothermal Power Station. The Cerro Prieto spreading center intersects the southern end of the Imperial Fault and the northern end of the Cerro Prieto Fault.Fuis, Gary S. and Walter D. Mooney''Salton Trough'' Lithospheric Structure and Tectonics from Seismic-Refraction and Other Data'' in USGS Professional Paper 1515/ref> Both of these are transform faults in the northern leg of the East Pacific Rise system that runs the length of the Gulf of California and is steadily rifting the Baja California peninsula away from the mainland of Mexico Mexico, officially the United Mexican States, is a country in North America. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Rock
Volcanic rocks (often shortened to volcanics in scientific contexts) are rocks formed from lava erupted from a volcano. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into hypabyssal and metamorphic rocks and constitute an important element of some sediments and sedimentary rocks. For these reasons, in geology, volcanics and shallow hypabyssal rocks are not always treated as distinct. In the context of Precambrian shield geology, the term "volcanic" is often applied to what are strictly metavolcanic rocks. Volcanic rocks and sediment that form from magma erupted into the air are called "pyroclastics," and these are also technically sedimentary rocks. Volcanic rocks are among the most common rock types on Earth's surface, particularly in the oceans. On land, they are very common at plate boundaries and in flood basalt provinces. It has been estimated that volcanic rocks cover about 8% of the Earth's current land surface. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuff
Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock. Rock that contains greater than 75% ash is considered tuff, while rock containing 25% to 75% ash is described as ''tuffaceous'' (for example, ''tuffaceous sandstone''). A pyroclastic rock containing 25–75% volcanic bombs or volcanic blocks is called tuff breccia. Tuff composed of sandy volcanic material can be referred to as volcanic sandstone. Tuff is a relatively soft rock, so it has been used for construction since ancient times. Because it is common in Italy, the Romans used it often for construction. The Rapa Nui people used it to make most of the ''moai'' statues on Easter Island. Tuff can be classified as either igneous or sedimentary rock. It is usually studied in the context of igneous petrology, although it is sometimes described using sedimentological terms. Tuff is often erroneously called t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fracture Zone
A fracture zone is a linear feature on the ocean floor—often hundreds, even thousands of kilometers long—resulting from the action of offset mid-ocean ridge axis segments. They are a consequence of plate tectonics. Lithospheric plates on either side of an active transform fault move in opposite directions; here, strike-slip activity occurs. Fracture zones extend past the transform faults, away from the ridge axis; are usually seismically inactive (because both plate segments are moving in the same direction), although they can display evidence of transform fault activity, primarily in the different ages of the crust on opposite sides of the zone. In actual usage, many transform faults aligned with fracture zones are often loosely referred to as "fracture zones" although technically, they are not. They can be associated with other tectonic features and may be subducted or distorted by later tectonic activity. They are usually defined with bathymetric, gravity and magneti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tortuga Island, Baja California Sur
Isla Tortuga (Tortuga Island) is an island in the Gulf of California, created relatively recently in geologic terms by the volcanism associated with the East Pacific Rise. It lies east-northeast of the city of Santa Rosalía, in Mulegé Municipality. It has a surface area of 11.374 km2 (4.39 sq mi). (in Spanish). Biology The Tortuga Island rattlesnake (''Crotalus tortugensis'') is a |
Basaltic
Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron ( mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of Venus, which cover ~80% of the surface, are basaltic; the lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flows that can spread over great areas before cooling and solidifying. Flood basalts are thick s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santa Rosalía, Baja California Sur
Santa Rosalía is a city and municipal seat of Mulegé Municipality, in Baja California Sur, situated along the Gulf of California. Located on the east coast of the Baja Peninsula, the town had a population of 14,357 inhabitants in 2020. The city was founded as a company town by the French Compagnie du Boleo in 1884, which established the local copper mines. Today the city is a popular tourist destination. History The town was named after Saint Rosalia, although the mission is not located by the town, but is in original location Mulegé, about south. Santa Rosalía boasts French influence, particularly in its architecture. The French Compagnie du Boleo founded the town in 1884 and exploited copper mines there until they closed in 1954. They built houses and installed the metallic Iglesia de Santa Bárbara. Unlike many other mining sites, the industrial facilities which are located in the very middle of the town, were never dismantled. Of particular interest are th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baja California
Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of Baja California (). It has an area of (3.57% of the land mass of Mexico) and comprises the northern half of the Baja California peninsula, north of the 28th parallel, plus oceanic Guadalupe Island. The mainland portion of the state is bordered on the west by the Pacific Ocean; on the east by Sonora, the United States on the north and on the south by Baja California Sur. The state has an estimated population of 3,769,020 as of 2020, significantly higher than the sparsely populated Baja California Sur to the south, and similar to San Diego County, California, and Imperial County, California, to its north. Over 75% of the population lives in Mexicali (the state's capital city), Ensenada, or Tijuana (the state's largest city). Other impo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
