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An analysis of rocks in South Africa has revealed the existence of a diverse ecosystem that thrived in the sea 3.4 billion years ago, suggesting an even earlier origin of life on Earth. The rocks, which are 3.42 billion years old, contain microscopic blobs of carbon-based matter believed to be the remains of microorganisms. The chemical makeup of these blobs indicates that there were photosynthetic microbes living near the surface of the sea, as well as other microbes that fed on waste products produced by the photosynthetic organisms. This study provides further evidence for an early origin of life on Earth, although the earliest history of life remains unknown due to a lack of well-preserved rocks. [Extracted from the article]

Scientists studying rocks in eastern South Africa have found evidence of an earthquake that occurred over 3 billion years ago, triggered by plate tectonics. This discovery raises questions about when plate tectonics first emerged on Earth, a topic that has been debated among geologists. The rocks in the Barberton Greenstone Belt in South Africa, which range in age from 3.2 billion to 3.6 billion years old, show signs of being churned by giant submarine landslides, which are typically associated with earthquakes caused by tectonic plate collisions. While some researchers believe plate tectonics emerged about 2.8 billion years ago, others argue it began much earlier. The study provides solid evidence based on fieldwork, but there are differing opinions among scientists about the initiation of plate tectonics. [Extracted from the article]

A palinspastic reconstruction of a 100 km long traverse through Archaean rocks of the East Pilbara, Western Australia, includes new observations of the deformation preceding the now visible greenstone belt pattern. The restoration is time-calibrated with all available U-Pb datings. Between incompletely preserved basin sequences, two superposed Palaeoarchaean volcano-sedimentary basins (the Coongan and Salgash Basins) are separated by an eastwards time-transgressive interface tentatively interpreted as an onlap surface. For over 140 Ma, the basin margin architecture was structurally controlled by superposed extensional growth fault arrays (D1) with associated dyke swarms in a curved pattern spatially not related to that of the actual distribution of granite domes and greenstone belts. The basins are interpreted to have formed by collapse after arching above hotspots due to phase transitions by mini-subduction of slabs of cooled water-saturated basalt towards the base of an originally c. 45 km mafic crust. At c. 3.31 Ga, the extension was replaced by plate-driven regional NW-SE compression (D2) inferred from NW-over-SE shear and ramp-and-flat thrusts, partly reversing offsets of the D1 extension. The recognition of widespread D2 pre-doming compression is important because it triggered the c. 3.18 Ga start of formation of the dome-and-keel pattern (D3) visible today, which culminated at c. 2.9 Ga. [ABSTRACT FROM AUTHOR]

Now, an international team of researchers led by geobiologist Barbara Cava-lazzi at the University of Bologna, Italy, has discovered evidence of fossilized microbes dating to roughly 3.42 billion years ago in a hydrothermal system just under the seafloor. The presence of certain nickel compounds in a hydrothermal environment suggests that the putative microbes likely produced or used methane in their metabolism, as modern microbes do in similar anoxic environments today. From the collective evidence, the researchers conclude that these microfossils represent the oldest methane-cycling archaea microbes found in a subsurface environment. [Extracted from the article]

Presents information on a study which described the stratigraphic marker horizons from greenstone belts in Zimbabwe, the Belingwe, Midlands and Bindura-Shamva. Background information on iron formations; Tectonic ironstones of the Belingwe greenstone belt; Discussion of the tectonic ironstones of the Midlands greenstone belt.

The article reports on the results of a study by Jonathan O'Neil of McGill University in Montreal, Canada and colleagues on the world's oldest rock and on the formation of the Earth's continents. They measured levels of neodymium-142 in rocks from the Nuvvuagittuq greenstone belt to northern Quebec to come up with the age of the rock at 4.28 billion years. The figure suggest that continents formed much earlier than thought.

The article offers information related to the Abitibi Greenstone belt, one of the world's largest Archean greenstone belts across the Ontario-Quebec border in Canada. It focuses on several gold mining sites of several companies in the area including Adventure Gold Inc.'s properties in Val-d'Or, Vancouver, the Lamaque Project of Integra Gold Corp. and Detour Gold Corp.'s Detour Lake mine in Ontario.

The article reports that Miramar Mining Corp. has increased its site activity, adding the Doris North mine in Nunavut, Canada and the Hope Bay greenstone belt have been pulled off resource expansion drilling to begin testing priority exploration targets. According to Tony Walsh, the firm's president and chief executive officer, the firm begun site activities to be prepared for production and the Hope Bay belt will be only the start of mining gold in the belt. The drilling for new discoveries has started with two drill rigs testing priority targets along the Madrid trend and other chosen targets. The firm also announced the re-start of the autoclave at the Con mine in Yellowknife, Northwest Territories, Canada.