Substantial accumulation of free oxygen in the atmosphere occurred between ~2.45 and 2.20 billion years ago , with permanent atmospheric oxygenation commencing between 2.3 and 2.2 Ga. This period is known as the Great Oxidation Event (GOE) and marks the most dramatic change in Earth’s surface chemistry and habitability. However, »
Queensland’s Early DaysBY C. Duncan LaidleyBrisbane Courier (Qld. : 1864 – 1933), Saturday 27 October 1923, page 19 I find it most interesting to read the Brisbane Courier from 100 years ago on a Saturday morning. It brings into stark relief the modern world, that which remains much the same »
Charles Collin was the son of Jules Andre Colin de Souvigny, who with the family emigrated to Brisbane, Australia in 1826, from Poitier, France. During the passage they shortened the family name to Colin likely to accommodate English sensitivities. Gustav Colin, the lad to center right of the image below, »
This post is a summary of the excellent recent paper on the above topic in Economic Geology: Jeffrey W. Hedenquist, Antonio Arribas; Exploration Implications of Multiple Formation Environments of Advanced Argillic Minerals. Economic Geology 2022;; 117 (3): 609–643. https://doi.org/10.5382/econgeo.4880 Introduction Hydrothermal ore deposits are associated with alteration minerals, and one such alteration type »
I find it most interesting to read the Brisbane Courier from 100 years ago on a Saturday morning. It brings into stark relief the modern world, that which remains much the same and that which has evolved beyond belief in such a short period of time. Here is a transcription »
Introduction The Earth’s lithosphere is its rigid outer shell, which rests on the more fluid asthenosphere. The thickness of the lithosphere varies, from a few kilometers at ocean spreading centers to 250-300 kilometers within continental cratons. There are two significant seismic boundaries in the crust and upper mantle: the Mohorovicic »
