Pg. 26-43. Rio Grande series. Called the river gravels overlying Cretaceous sandstones and shales in environs of Albuquerque [central northern New Mexico] Rio Grande series, also Albuquerque series, and divided them into (descending): (1) yellowish white marl, 6 feet, "which occurs on both sides of Rio Grande, and which may henceforth be known as the Albuquerque marl," (2) gravel and rounded sands, 2 to 20+ feet thick, evidently the debris from the metamorphic series, and designated "Rio Grande gravels," (3) sandy loess passing into clay, depth not known, but recognized everywhere, designated "Rio Grande loess." [Age is late Tertiary.]

Source: US geologic names lexicon (USGS Bull. 896, p. 1816-1817).

Rio Grande gravels extend up Gallisteo Creek and form part of group described there as Santa Fe marl. One of most prominent features of deposits of valley is the marl bed which caps the mesas. That over Sandia Mesa has been described by Herrick as Albuquerque marl, while that on Albuquerque Mesa he called Santa Fe marl. It seems best to place both under one name --Albuquerque marl. [See also under Rio Grande loess.]

Source: US geologic names lexicon (USGS Bull. 896, Rio Grande series entry p. 1816-1817).