The Rôle of humus in the geochemical enrichment of u in coal and other bioliths

Geology of uranium in coaly carbonaceous rocks

“…Meanwhile uranium-bearing coal was reported by Foldvari and Szalay in Hungary in the vicinity of the Mecsek and Velence Mountains (Szalay, 1954). Though the exact date of their discovery is not mentioned, it is presumed to be prior to 1951. Interest in coaly carbonaceous rocks as a potential source for uranium fluctuated widely.…”

“…In a later paper, Szalay (1957) showed that for low concentrations, the uranium in peat is about 10,000 times that in the water in which it is in equilibrium. Experiments are also described which show that the fixation of the uranyl ions is a cation-exchange process whereby H-ions are replaced by UO2+2 ions and that the adsorbed uranyl ion can be easily exchanged by cations of higher valency and high atomic weight such as Th+4 and La+3.…”

“…The salts of organic acids such as humates are commonly associated with coaly rocks (Hawkes, 1957, p. 259). Considerable evidence indicates that uranium humates form readily from the decomposition of vascular plant substances (Szalay, 1954(Szalay, , 1957Manskaya, Drozdova, and Emelyanova, 1956;Vine, Swanson, and Bell, 1958). Working with low concentrations of uranium in solution, Szalay (1957, p. 29) showed that peat at equilibrium will contain about 10,000 times greater concentration of uranium than associated water.…”

Geological Survey Research 1966, Chapter C

“…Some of these other studies involved peat, dopplerite, lio-nite, soil humus, humic acids, and humate (Aschan, b • 1932;Horner and others, 1934, p. 665, 668;Hewitt, 1952, p. 106-107;Rozhkova and Shcherbak, 1956;Szalay, 1957;Vine and others, 1958;Martin, 1960;· Kashirtseva, 1960 ;Fraser, 1961 ;Mortensen, 1963) , which can sorb from a few percent to 20 percent metal hy dry weight.…”

Proceedings of the Second U.S. Geological Survey workshop on the early Mesozoic basins of the Eastern United States

“…organic material that is characterized by numerous oxygen-bearing functional groups has a greater affinity for metals than do other types of organic material (Schnitzer and Khan, 1978). Humic substances, in particular, are known to be effective concentrators of uranium (Szalay, 1958), whereas hydrocarbons generally are not (Andreyev and Chumachenko, 1964). New data indicate that many of the Jurassic lacustrine beds in the Newark basin have organic characteristics and thermal maturity making them suitable as hydrocarbon source beds Hatcher and Romankiw, chapter 11, this volume; Pratt and others, chapter 13, Reading Prong.…”