Background (Ba,Sr)SO4 solid-solutions range among the most important scaling minerals, not only in geothermal energy production, but generally in applications involving hydrothermal brines, e.g. including petroleum production [e.g. (Todd and Yuan 1990, 1992; Kühn et al. 1997)]. Besides the general difficulties related to scale formation, like blockage of pipes, related decrease of well producti...

An attempt was made to apply Mn-impregnated acrylic fiber to the collection of small amounts of Ra isotopes in natural waters. The Mn compound incorporated in this material was estimated to be KMn8O16•E H2O, which occurred naturally in Japan as cryptomelane. Collection by the Mn-impregnated acrylic fiber was effective in the pH region higher than 4 and the collecting efficiency was dependent on...

Radium isotopes have been used to trace nutrient, carbon, and metal fluxes inputs from ocean margins. However, these approaches require a full accounting of radium sources the coastal including rivers. Here, we aim quantify river into Arctic Ocean for first time 226Ra refine estimates 228Ra. Using new existing data, find that estimated combined (dissolved plus desorbed) annual 228Ra are [7.0–9....

Radium isotopes (Ra, Ra, Ra, and Ra) and water chemistry were used to identify two chemically distinct sources of submarine groundwater discharge (SGD) in Celestún Lagoon, Yucatán, Mexico. Low salinity groundwater discharging from springs within the lagoon has previously been identified and extensively sampled for nutrient concentrations. However, a second type of groundwater discharging into t...

Near- and off-shore fresh groundwater resources become increasingly important with the social and economic development in coastal areas. Although large scale (hundreds of km) submarine groundwater discharge (SGD) to the ocean has been shown to be of the same magnitude order as river discharge, submarine fresh groundwater discharge (SFGD) with magnitude comparable to large river discharge is nev...

Rare earth element (REE) concentrations and neodymium isotopic composition (ɛNd) are tracers for ocean circulation and biogeochemistry. Although models suggest that REE release from lithogenic sediment in river discharge may dominate all other REE inputs to the oceans, the occurrence, mechanisms and magnitude of such a source are still debated. Here we present the first simultaneous observation...

Since the 1960s, thorium isotopes occupy a special place in the oceanographer’s toolbox as tracers for determining rates and mechanisms of oceanic scavenging, particle dynamics, and carbon fluxes. Due to their unique and constant production rates from soluble parent nuclides of uranium and radium, their disequilibrium can be used to calculate rates and time scales of sinking particles. In addit...