Alfred Hulse Brooks (July 18, 1871 – November 22, 1924) was an American geologist and served as chief geologist for Alaska for the United States Geological Survey from 1903 to 1924. He is credited with discovering that the biggest mountain range in Arctic Alaska, now called the Brooks Range, was separate from the Rocky Mountains.
He was a native of Ann Arbor, Michigan, and graduated from Harvard University in 1894. After his graduation, he also studied in Germany and Paris. In 1898, the federal government announced a systematic topographic and geologic survey of Alaska that would include renewed exploration of the Brooks Range. Alfred Hulse Brooks, the new assistant geologist and head of the Alaskan branch of the United States Geological Survey (USGS), called the project "far more important than any previously done," due in large part because it "furnished the first clue to the geography and geology of the part of Alaska north of the Yukon Basin." Between 1899 and 1911, six major reconnaissance expeditions traversed the mountain range, mapping its topography and geology and defining the patterns of economic geology so important to prospectors and miners. He was appointed geological curator of Alaskan mineral resources 1902.
Every year from 1904 to 1916 and from 1919 to 1923, Brooks wrote summaries of Alaska's mineral industries. The missed years, during World War I, were those that he spent in France as chief geologist for the American Expeditionary Force in France.