The Proterozoic is a geological eon spanning the time from the appearance of oxygen in Earth's atmosphere to just before the proliferation of complex life on the Earth. The name Proterozoic combines the two forms of Greek origin: protero- meaning "former, earlier", -zoic, a suffix related to zoe "life"; the Proterozoic Eon extended from 2500 mya to 541 mya, is the most recent part of the Precambrian "supereon." The Proterozoic is the longest eon of the Earth's geologic time scale and it is subdivided into three geologic eras: the Paleoproterozoic and Neoproterozoic. The well-identified events of this eon were the transition to an oxygenated atmosphere during the Paleoproterozoic; the geologic record of the Proterozoic Eon is more complete than that for the preceding Archean Eon. In contrast to the deep-water deposits of the Archean, the Proterozoic features many strata that were laid down in extensive shallow epicontinental seas. Studies of these rocks have shown that the eon continued the massive continental accretion that had begun late in the Archean Eon.

The Proterozoic Eon featured the first definitive supercontinent cycles and wholly modern mountain building activity. There is evidence; the first began shortly after the beginning of the Proterozoic Eon, evidence of at least four during the Neoproterozoic Era at the end of the Proterozoic Eon climaxing with the hypothesized Snowball Earth of the Sturtian and Marinoan glaciations. One of the most important events of the Proterozoic was the accumulation of oxygen in the Earth's atmosphere. Though oxygen is believed to have been released by photosynthesis as far back as Archean Eon, it could not build up to any significant degree until mineral sinks of unoxidized sulfur and iron had been exhausted; until 2.3 billion years ago, oxygen was only 1% to 2% of its current level. The Banded iron formations, which provide most of the world's iron ore, are one mark of that mineral sink process, their accumulation ceased after 1.9 billion years ago, after the iron in the oceans had all been oxidized. Red beds, which are colored by hematite, indicate an increase in atmospheric oxygen 2 billion years ago.

Such massive iron oxide formations are not found in older rocks. The oxygen buildup was due to two factors: exhaustion of the chemical sinks, an increase in carbon burial, which sequestered organic compounds that would have otherwise been oxidized by the atmosphere; the Proterozoic Eon was a tectonically active period in the Earth's history. The late Archean Eon to Early Proterozoic Eon corresponds to a period of increasing crustal recycling, suggesting subduction. Evidence for this increased subduction activity comes from the abundance of old granites originating after 2.6 Ga. The occurrence of eclogite, is explained using a model; the lack of eclogites that date to the Archean Eon suggests that conditions at that time did not favor the formation of high grade metamorphism and therefore did not achieve the same levels of subduction as was occurring in the Proterozoic Eon. As a result of remelting of basaltic oceanic crust due to subduction, the cores of the first continents grew large enough to withstand the crustal recycling processes.

The long-term tectonic stability of those cratons is why we find continental crust ranging up to a few billion years in age. It is believed that 43% of modern continental crust was formed in the Proterozoic, 39% formed in the Archean, only 18% in the Phanerozoic. Studies by Condie and Rino et al. suggest. By isotopically calculating the ages of Proterozoic granitoids it was determined that there were several episodes of rapid increase in continental crust production; the reason for these pulses is unknown, but they seemed to have decreased in magnitude after every period. Evidence of collision and rifting between continents raises the question as to what were the movements of the Archean cratons composing Proterozoic continents. Paleomagnetic and geochronological dating mechanisms have allowed the deciphering of Precambrian Supereon tectonics, it is known that tectonic processes of the Proterozoic Eon resemble the evidence of tectonic activity, such as orogenic belts or ophiolite complexes, we see today.

Hence, most geologists would conclude. It is commonly accepted that during the Precambrian, the Earth went through several supercontinent breakup and rebuilding cycles. In the late Proterozoic, the dominant supercontinent was Rodinia, it consisted of a series of continents attached to a central craton that forms the core of the North American Continent called Laurentia. An example of an orogeny associated with the construction of Rodinia is the Grenville orogeny located in Eastern North America. Rodinia formed after the breakup of the supercontinent Columbia and prior to the assemblage of the supercontinent Gondwana; the defining orogenic event associated with the formation of Gondwana was the collision of Africa, South America, Antarctica and

Max Scherr

Max Scherr was an American underground newspaper editor and publisher known for his iconoclastic 1960s weekly, the Berkeley Barb. Max Scherr was born in Maryland, on March 12, 1916, in a Jewish household, his parents, Harry Scherr, a tailor, Minnie, were Yiddish-speaking Russian immigrants who arrived in America in 1898. His early life is obscure. From 1935 to 1938, he attended law school at the University of Maryland, earning his law degree in June, 1938. For the next three years he practiced law in Baltimore, including serving as legal counsel to Local 175 of the CIO-affiliated Transport Workers Union in a 1941 Baltimore taxi drivers strike. During World War II he served in the Navy. After demobilization he attended the University of California, earning a master's degree in sociology in 1949. On a trip to Mexico in the 1940s he married Juana Estela Salgado, a medical student. Together, they had a daughter, Raquel Lorraine Scherr, born in 1947, two sons and David Scherr. Returning to California, they lived in Albany, Berkeley, where Max Scherr worked for a publisher of legal textbooks, hanging out after work at a coffee shop called Il Piccolo Espresso, where he kibbitzed with local bohemians and radicals.

By the end of the 1950s "The Pic" had become an important meeting place for SLATE, the progressive student party at U. C. Berkeley. In 1958, Scherr purchased a local hangout popular with students and beatniks called the Steppenwolf at 2136 San Pablo Avenue, which became a stop on the West Coast folk music circuit. Scherr ran the Steppenwolf for seven years, selling it in 1965 for $10,000, which he used to launch the Barb; the first issue of the Barb was dated August 13, 1965. Two thousand copies were sold. According to legend, Scheer started the paper after a projected local paper to be published by the Berkeley food co-op failed to appear. Scoffing at the claim that it would cost $43,000 to launch a small local paper in Berkeley, he boasted that he would have the first issue out in a week. Around 1960 Scherr had split from Juana Estela Salgado and moved in with a much younger woman named Jane Peters, with whom he had two daughters and Apollinaire. By 1965 they had moved into a colonnaded house at 2421 Oregon Street.

Coming home from the food co-op, he informed Peters that they had to put a paper out in one week "or I'll be the laughingstock of Berkeley." At the end of the week the promised paper written by Scherr, appeared. The smudgy first issue of 8 tabloid pages was crudely printed in a small edition of 2000 copies, the paper was launched on a run which lasted 15 years; the Barb became the news and communications center for the militant New Left protest movements swirling around the Berkeley campus of the University of California, where the Free Speech Movement made nationwide headlines in 1964. By the fall of 1965 antiwar protest led by the Vietnam Day Committee and Jerry Rubin dominated campus activism in Berkeley, the Barb soon emerged as the unofficial mouthpiece of the VDC. In the San Francisco Bay Area the paper provided a radical alternative to the stodgy conservatism and anticommunism of the established local press, dominated by Hearst's San Francisco Examiner, the Chronicle and William Knowland's Oakland Tribune.

Max Scherr considered himself and the paper to be part of the revolutionary left, although he had never been in any organized left-wing party, the paper's news coverage was seen as baiting the police and authorities in Berkeley, with inflammatory headlines like "Pigs Shoot to Kill—Bystanders Gunned Down." The battle over People's Park which began in 1969 with an article by Stew Albert in the Barb was in some respects the paper's high-water mark in arousing its readers to militant activism in the streets, but the bitter aftermath, in which several protestors were shot and the city was occupied by the National Guard, left many in Berkeley with little appetite for further confrontation. The paper grew developing a nationwide following, by mid-1969 Time reported that the paper was circulating 86,000 copies and charging $450 a page for advertising, turning an annual profit of $150,000; this led to conflict with the paper's staff of 40, earning at most the legal minimum wage, the staff rebelled, forming the Red Mountain Tribe collective and issuing a special interim edition called Barb on Strike without Scherr, who managed to put out a bare-bones 8-page issue of the paper on schedule without assistance.

Scherr succeeded in getting the Tribe out of the paper's offices, whereupon he moved the newspaper's equipment into a new office and hired a new staff. The Red Mountain Tribe retaliated by starting their own competing paper, the Berkeley Tribe, which lasted until 1972. In 1970 Scherr announced the sale of the Barb to anthropology professor Allan Coult, but the sale fell through and it was soon back in Scherr's hands. In 1973 he set up a dummy shell corporation in Panama to control the paper and keep it out of the hands of Jane Peters, who filed for divorce in 1974 as his common law wife, demanding half of the paper, it transpired that Scherr and a tax shelter lawyer named Harry Margolis had arranged to sell the paper to a non-profit foundation in exchange for $2000 a month for life for Scherr, while a dummy corporation in the British Virgin Islands controlled the paper's assets. Scherr stayed on as editor emeritus until 1978; the Barb continued to decline. In 1978, with sales down to 20,000 copies, in an effort to attract mainstream advertisers, the paper's lucrative sex ads were spun off into a separate publi

Norbert Brodine

Nobert Brodine credited as Norbert F. Brodin and Norbert Brodin, was a film cinematographer; the Saint Joseph, Missouri-born cameraman worked on over 100 films in his career before retiring from film making in 1953, at which time he worked in television until 1960. Brodine began his cameraman career working in a camera shop and building on that experience in the Army Signal Corps, as an army photographer during World War I. After studying at Columbia University, he began working as a still photographer in Hollywood before moving to motion pictures in 1919, he began working for Hal Roach Studios in 1937 and moved on to 20th Century Fox in 1943. Brodine's films include the sought after lost film A Blind Bargain starring Lon Chaney, This Thing Called Love, The Death Kiss, Counsellor at Law, The House on 92nd Street, Somewhere in the Night, Kiss of Death, Thieves' Highway, 5 Fingers. Brodine shot several films with Laurel and Hardy at both Roach and Fox, such as Pick a Star, Swiss Miss, The Dancing Masters, The Bullfighters.

Brodine moved back to Hal Roach Studios to end his film career in the early 1950s. He worked in television from 1952 to 1960, finished his career on the well-known television series The Loretta Young Show, for which he won a Primetime Emmy Award. Brodine died at the age of 73, on February 28, 1970, he was buried at Forest Lawn Memorial Park Cemetery in Glendale, Los Angeles County, California Racket Squad, TV series, 40 episodes Letter to Loretta, TV series, 65 episodes Crown Theatre with Gloria Swanson, TV series, 4 episodes Our Gang, series cinematography for 1938 Norbert Brodine on IMDb