The Mesozoic continental volcanic rocks are widely distributed in South China. Volcanicactivities started at 175 Ma and ended at 75 Ma. They are characterized by highly potassiccafe-alkaline volcanic series at the early stage and bimodal volcanic rocks at the late stage.
The paper describes the isotopic characters of hydrogen, oxygen, sulfur, and fluid inclusion characters in geology, and discusses the metallogeny, metallogenic regularities and prospecting indicators for subvolcanic copper-silver-gold-lead-zinc polymetallic deposits in the Mesozoic terrestrial volcanic region of east China.
On the basis of comprehensive regional reconnaissance the author suggests that the Tianmujian basin located at the eastern part of Gan Han tectonic belt is a large volcanic collapse basin with good U metallogenic conditions, and one of the favourable target areas for volcanic type rich large U deposit.
Soil process is not always required to "filter' metalliferous continental volcanics and concentrate the ore.
Geochemical stratigraphy of the Huronian continental volcanics at Thessalon, Ontario: contributions of two-stage crustal fusion
The 1500 m thick sequence of Huronian continental volcanics at Thessalon, Ontario is subdivided into 4 volcanic cycles, each of which includes abundant early mafic end-members, central intermediate flows, and late rhyolite units.
This makes it possible to consider these rocks as components of a single continental volcanic-plutonic belt.
The continental volcanic-subvolcanic (porphyry) rock-type Ag deposits were formed later than the country rocks.
In addition, this study also deals with the geochemical characteristics of the continental volcanic-subvolcanic rock-type Ag deposits and the relations between Ag deposits or silver itself and fluorite, halogen-family elements and manganese.
Lavas in the field exhibit medium-K, calc-alkaline affinities, typical of continental volcanic arcs along convergent plate margins.
Two of these fractures, dipping toward the subduction zone, may be considered as the principal feeding channels for active and Holocene volcanoes of the continental volcanic belts of Kamchatka.