Rift valley

A rift valley is a linear shaped lowland between several highlands or mountain ranges created by the action of a geologic rift or fault. A rift valley is formed on a divergent plate boundary, a crustal extension or spreading apart of the surface, subsequently further deepened by the forces of erosion; when the tensional forces are strong enough to cause the plate to split apart, a center block drops between the two blocks at its flanks, forming a graben. The drop of the center creates the nearly parallel steeply dipping walls of a rift valley when it is new; that feature is the beginning of the rift valley, but as the process continues, the valley widens, until it becomes a large basin that fills with sediment from the rift walls and the surrounding area. One of the best known examples of this process is the East African Rift. On Earth, rifts can occur at all elevations, from the sea floor to plateaus and mountain ranges in continental crust or in oceanic crust, they are associated with a number of adjoining subsidiary or co-extensive valleys, which are considered part of the principal rift valley geologically.

The most extensive rift valley is located along the crest of the mid-ocean ridge system and is the result of sea floor spreading. Examples of this type of rift include the East Pacific Rise. Many existing continental rift valleys are the result of a failed arm of a triple junction, although there are two, the East African Rift and the Baikal Rift Zone, which are active, as well as a third which may be, the West Antarctic Rift. In these instances, not only the crust but entire tectonic plates are in the process of breaking apart to create new plates. If they continue, continental rifts will become oceanic rifts. Other rift valleys are the result of discontinuities in horizontally-moving faults; when these bends or discontinuities are in the same direction as the relative motions along the fault, extension occurs. For example, for a right lateral-moving fault, a bend to the right will result in stretching and consequent subsidence in the area of the irregularity. In the view of many geologists today, the Dead Sea lies in a rift which results from a leftward discontinuity in the left lateral-moving Dead Sea Transform fault.

Where a fault breaks into two strands, or two faults run close to each other, crustal extension may occur between them, as a result of differences in their motions. Both types of fault-caused extension occur on a small scale, producing such features as sag ponds or landslides. Many of the world's largest lakes are located in rift valleys. Lake Baikal in Siberia, a World Heritage Site, lies in an active rift valley. Baikal is both the deepest lake in the world and, with 20% of all of the liquid freshwater on earth, has the greatest volume. Lake Tanganyika, second by both measures, is in the Albertine Rift, the westernmost arm of the active East African Rift. Lake Superior in North America, the largest freshwater lake by area, lies in the ancient and dormant Midcontinent Rift; the largest subglacial lake, Lake Vostok, may lie in an ancient rift valley. Lake Nipissing and Lake Timiskaming in Ontario and Quebec, Canada lie inside a rift valley called the Ottawa-Bonnechere Graben. Þingvallavatn, Iceland's largest natural lake, is an example of a rift lake.

Extraterrestrial rift valleys are known to occur on other terrestrial planets and natural satellites. The 4,000 km long Valles Marineris on Mars is believed by planetary geologists to be a large rift system; some features of Venus, most notably, the 4,000 km Devana Chasma and a part of the western Eistla, also Alta and Bell Regio have been interpreted by some planetary geologists as a rift valleys. Some natural satellites have prominent rift valleys; the 2,000 km long Ithaca Chasma on Tethys in the Saturn system is a prominent example. Charon's Nostromo Chasma is the first confirmed in the Pluto system, however large chasms up to 950 km wide observed on Charon have been tentatively interpreted by some as giant rifts, similar formations have been noted on Pluto. A recent study suggests a complex system of ancient lunar rift valleys, including Vallis Rheita and Vallis Alpes; the Uranus system has prominent examples, with large'chasma' believed to be giant rift valley systems, most notably the 1492 km long Messina Chasma on Titania, 622 km Kachina Chasmata on Ariel, Verona Rupes on Miranda, Mommur Chasma on Oberon.

Bonatti, E. "Punctiform initiation of seafloor spreading in the Red Sea during transition from a continental to an oceanic rift". Nature. 316: 33–37. Bibcode:1985Natur.316...33B. Doi:10.1038/316033a0. Mart, Y.. "Analogue experiments of propagation of oblique rifts". Tectonophysics. 316: 121–132. Bibcode:2000Tectp.316..121M. Doi:10.1016/s0040-195100231-0

Miguel Ángel Riquelme Solís

Miguel Ángel Riquelme Solís is a Mexican politician from the Institutional Revolutionary Party and the current Governor of Coahuila. Riquelme Solís was born in Torreón, Coahuila, on 18 September 1970, he attended the Instituto Tecnológico de La Laguna, where he studied computer engineering and was the president of the student body between 1991 and 1993. He became a tax collector in the nearby town of Matamoros, Coahuila, in 1994, bouncing between the tax collection offices of Matamoros and Torreón, he joined the PRI, working on the campaign staff of a candidate for state deputy in 1996 and coordinating political operatives for a federal deputy campaign in 1997. In 1999, he ran for state deputy from a district in Torreón. In 2000, Riquelme joined the state government, overseeing social welfare programs in the Laguna region for most of the government of Enrique Martínez y Martínez. After a brief stint in the Coahuila state legislature between 2005 and 2007, he headed up social welfare efforts in the state secretariat of regional development and was named the head of the Laguna office of that agency.

In 2009, voters in Coahuila's fifth federal electoral district elected Riquelme as their deputy to the LXI Legislature of the Mexican Congress. He held four commission assignments, including a secretary post on the Metropolitan Development Commission. On February 10, 2011, Riquelme permanently took leave from the Chamber of Deputies; when Rubén Moreira Valdez's government came into power, Riquelme was named the state secretary of government. Three years in 2014, Riquelme was elected the municipal president of Torreón. Among the large projects taken up by the municipal government during his term was a cable car to the Cristo de las Noas statue. In December 2016, during the reading of his third government address as mayor, Riquelme announced he would step aside as mayor in order to compete for the PRI gubernatorial nomination. In the internal PRI election, he earned 90 percent of the vote to secure the nomination; the gubernatorial campaign was contested and narrowly won by Riquelme by a margin of 2.5 percentage points over National Action Party candidate Guillermo Anaya Llamas.

Riquelme's win was challenged due to allegations. In 1992, Riquelme married Blanca Marcela, with whom he has two daughters

Hugo Badalić

Hugo Badalić was a Croatian writer. Badalić attended primary school in his native city and Kostajnica, the gymnasium in Zagreb. After finishing the gymnasium he went to university in Vienna where he graduated with a degree in Classical philology in 1874; the same year he was appointed as a teacher of the Grandy Gymnasium in Zagreb. In 1879 he served as a professor at the gymnasium in Rijeka, returning in 1882 to Zagreb where he worked at the gymnasium in Gornji Grad. From 1884, he served as the director of a female high school in Zagreb, from 1896 as the first director of the newly established Grand Gymnasium in Zagreb's Donji Grad, he published writings in Agramer Tagblatt, Hrvatska vila and many other periodicals. In 1884, he was elected to the committee of Matica hrvatska, where he edited a number of Matica's editions among which the collection of poetry Hrvatska antologija can be singled out as the most notable. Badalić was the author of numerous literary discussions, pedagogic articles, together with Ivan Broz, wrote the mandatory high-school handbook Poetika i stilistika za Hrvatsku čitanku za niže razrede srednje škole.

He published a collection of romantic songs: "Zlatno doba". As a gymnasium student Badalić edited the periodical Ljiljan where he published his first poem in 1867, he received literary recognition with the historic poem circenes. Badalić's poetry, published in his Izabrane pjesme, quite popular at the time, set to music according to Illyrian customs, is represented in modern anthologies, his poetry encompasses various literary genres, including romantic and elegies, thematically focussing to patriotic and occasional motifs. Based on the drama Nikolas Graf von Zriny oder die Belagerung von Sigeth by German Romanticist Theodor Körner, which premièred the opening of the new theatre building at St. Mark's Square in 1834, Badalić wrote the libretto for the historical opera Nikola Šubić Zrinski by Ivan Zajc, he was a translator of theatrical pieces by Scribe and Deschamps, Shakespeare and other authors. Fališevac, Dunja.