Standard Oil Company of Iowa was created in 1885 as a subsidiary of the Standard Oil Trust to handle marketing along the Pacific Coast states of Idaho, Oregon, Washington, California, and Arizona.
 Though named for the midwestern state, it never included Iowa as one of its primary marketing areas.
 A prior company named Standard Oil of California had been formed in 1877, and was not associated with the Standard Oil Trust.
 In 1906, Standard Oil of Iowa was dissolved and its assets handed over to a new Standard Oil of California, later Chevron Oil Company, and now the Chevron Corporation.
 Standard Oil Company of Iowa is thus the original company that is now Chevron.
The Magnolia Petroleum Company was an early twentieth century petroleum company in Texas founded on April 24, 1911 by the Sealy family of Galveston, as a consolidation of several earlier companies.
 Standard Oil of New York (Socony) exchanged its stock for all of the Magnolia stock (except seven shares for the Directors) in December 1925 though it continued to operate as an affiliate of Socony.
 Socony merged with Vacuum Oil Company in 1931, becoming Socony-Vacuum Oil Company.
 Magnolia Petroleum continued to operate as a subsidiary of Socony-Vacuum.
 In 1959, Magnolia was fully incorporated into the Mobil division of Socony-Vacuum, which later changed its name to Socony Mobil and, ultimately to Mobil Mobil Oil Corporation.
Atlantic Petroleum was an oil company in the Eastern United States headquartered in Philadelphia, and a direct descendant of the Standard Oil Trust.
 It was also one of the companies that merged with Richfield Oil to form ARCO, now part of Tesoro.
 After an unsuccessful spinoff from ARCO, Atlantic was acquired by Sunoco in 1988.
The Arabian Gulf Oil Company (Agoco; Arabic: شركة الخليج العربي للنفط‎ ‎ ) is an oil company based in Benghazi, Libya, engaged in crude oil and natural gas exploration, production and refining.
 It was a subsidiary of the state-owned National Oil Corporation (NOC).
Exxon Mobil Corporation is an American multinational oil and gas corporation headquartered in Irving, Texas.
 It is the largest direct descendant of John D. Rockefeller's Standard Oil Company, and was formed on November 30, 1999 by the merger of Exxon (formerly Standard Oil Company of New Jersey) and Mobil (formerly the Standard Oil Company of New York).
The Digboi Refinery was set up at Digboi in 1901 by Assam Oil Company Ltd.
 The Indian Oil Corporation Ltd (IOC) took over the refinery and marketing management of Assam Oil Company Ltd. with effect from 1981 and created a separate division.
 This division has both refinery and marketing operations.
 The refinery at Digboi had an installed capacity 0.50 MMTPA (million metric tonnes per annum).
 The refining capacity of the refinery was increased to 0.65 MMTPA by modernization of refinery in July, 1996.
 A new delayed Coking Unit of 1,70,000 TPA capacity was commissioned in 1999.
 A new Solvent Dewaxing Unit for maximizing production of microcrystalline wax was installed and commissioned in 2003.
 The refinery has also installed Hydrotreater-UOP in 2002 to improve the quality of diesel.
 The MSQ Upgradation unit has been commissioned.
 A new terminal with state of the art facility is under construction and expected to be completed by 2016.
China National Offshore Oil Corporation, or CNOOC Group (Chinese: 中国海洋石油总公司 Pinyin: "Zhōngguó Háiyáng Shíyóu Zǒnggōngsī"), is a major national oil company in China.
 It is the third-largest national oil company in the People's Republic of China, after CNPC (parent of PetroChina) and China Petrochemical Corporation (parent of Sinopec).
 The CNOOC Group focuses on the exploitation, exploration and development of crude oil and natural gas in offshore China.
Atlantic Richfield Company (ARCO) is an American oil company with operations in the United States, Indonesia, the North Sea, and the South China Sea.
 It has more than 1,300 gas stations in the western part of the United States.
 ARCO was formed by the merger of East Coast–based Atlantic Refining and California-based Richfield Oil Corporation in 1966.
 A merger in 1969 brought in Sinclair Oil Corporation.
 It became a subsidiary of UK-based BP plc in 2000 through its BP West Coast Products LLC (BPWCP) affiliate.
 On August 13, 2012, it was announced that Tesoro would purchase ARCO and its refinery for $2.5 billion.
 However, the deal came under fire due to increasing fuel prices.
 Many activists urged state and federal regulators to block the sale due to concerns that it would reduce competition and could lead to higher fuel prices at ARCO stations (ARCO stations make up more than half of all stations with the lowest fuel prices in California).
 On June 3, 2013, BP sold ARCO and the Carson Refinery to Tesoro for $2.5 billion.
 BP sold its Southern California terminals (Vinvale, Colton, San Diego, Hathaway, and Hynes) to Tesoro Logistics LP, including the Carson Storage Facility.
 BP will continue to own the ampm brand and sell it to Tesoro for Southern California, Arizona, and Nevada.
 BP exclusively licensed the ARCO rights from Tesoro for Northern California, Oregon, and Washington.
John Davison Rockefeller Sr. (July 8, 1839 – May 23, 1937) was an American oil industry business magnate and philanthropist.
 Widely considered the wealthiest American of all time and the richest person in modern history, Rockefeller was born into a large family in upstate New York and was shaped by his con man father and religious mother.
 His family moved several times before eventually settling in Cleveland, Ohio.
The National Oil Corporation (NOC; Arabic: المؤسسة الوطنية للنفط‎ ‎ ) is the national oil company of Libya.
 It dominates Libya's oil industry, along with a number of smaller subsidiaries, which combined account for around 70% the country's oil output.
 Of NOC's subsidiaries, the largest oil producer is the Waha Oil Company (WOC), followed by the Arabian Gulf Oil Company (Agoco), Zueitina Oil Company (ZOC), and Sirte Oil Company (SOC).

Question: Where is the oil corporation located that is a direct descendant if the "wealthiest American of all time's" oil company?
Answer: Irving, Texas