Results 51 to 60 of about 16,696 (213)
Metasomatized lithospheric mantle for Mesozoic giant gold deposits in the North China craton [PDF]
, 2020 The origin of giant lode gold deposits of Mesozoic age in the North China craton (NCC) is enigmatic because high-grade metamorphic ancient crust would be highly depleted in gold.
Becker, Harry +9 more
core +1 more source
Microspherules Formed by Lightning Strikes
Meteoritics &Planetary Science, EarlyView.Abstract Natural microspherules are formed by high‐temperature processes and are present throughout the geologic record to the present day. We report the discovery of large numbers of microspherules recovered from a rock pavement in the Pilbara region, Western Australia.
M. R. Boyd, M. J. Genge, A. G. Tomkins
wiley +1 more source
The Exploration Significance of Ag/Au, Au/Cu, Cu/Mo, (Ag×Au)/(Cu×Mo) Ratios, Supra-ore and Sub-ore Halos and Fluid Inclusions in Porphyry Deposits: A Review [PDF]
Journal of Sciences, Islamic Republic of Iran, 2017 This paper documents the exploration significance of Ag/Au, Au/Cu, Cu/Mo and (Ag×Au)/Cu×Mo) ratios of the supra-ore and sub-ore halos versus fluid inclusion evolution for 24 Cu, 6 Cu- Mo and 10 Cu-Au porphyry deposits worldwide. The ratios are based only
H. Atapour
doaj
Geofluids, 2020 In general, porphyry Cu deposit is related to the highly oxidized ore-forming system. However, there are many porphyry Cu deposits that are related to the reduced ore-forming system, and the ore-forming characteristics of reduced porphyry Cu deposit are ...
Rui Liu, Genwen Chen, Jianxing Yang
doaj +1 more source
Yankuang ceshi, 2020 BACKGROUND The main types of copper deposits are porphyry and skarn types. Dacite porphyry is a rock type commonly developed in the porphyry Cu-Mo-Au system.
ZHAO Chen-hui +8 more
doaj +1 more source
Mountain‐top spherules: Criteria to identify natural and synthetic particles
Meteoritics &Planetary Science, EarlyView.Abstract Natural microspherules are important tracers of geologic and environmental processes in modern and ancient deposits. However, anthropogenic contamination can dilute natural collections by releasing synthetic microspherules into the environment.
M. R. Boyd, M. J. Genge
wiley +1 more source
RUDN Journal of Engineering Research, 2023 Porphyry copper deposits are accompanied by extensive aureoles of hydrothermally altered rocks which make it possible to detect them on satellite images in the absence of vegetation.
Hamza A. Mahmoud +4 more
doaj +1 more source
Disseminated sulphide mineralisation at Garbh Achadh, Argyllshire, Scotland [PDF]
, 1978 A brief investigation of low-grade copper mineralisation associated with a small, talc-alkaline porphyry intrusion of Caledonian age is described.
Ellis, R.A., Fortey, N.J., Marsden, G.R.
core
Aqueous alteration in C2‐ung Bells through the analysis of carbonates – Does a CR origin ring true?
Meteoritics &Planetary Science, EarlyView.Abstract Bells is an ungrouped carbonaceous chondrite that has in recent years been proposed as a CR‐an. This link to CR chondrites has previously been identified through the analysis of anhydrous silicates, for example, oxygen isotopic compositions of olivine (Marrocchi et al., 2023).
L. J. Riches +4 more
wiley +1 more source
Characterisation of gold from Fiji [PDF]
, 1995 This is a study of the variation in chemistry and inclusion mineralogy of bedrock and placer gold from Fiji. It forms part of a large project, undertaking gold characterisation from a wide range of geological environments in Ecuador, Zimbabwe ...
Henney, P.J., Naden, Jon
core