Latest news with #Archaean
Time of India
08-05-2025
- Business
- Time of India
Online approval system for mining schemes in place in Raj
Jaipur: The department of mines has introduced an online approval system for mining plans and schemes with the aim of streamlining processes and enhancing transparency in the sector. The portal is already operational, and it accepts applications for mining plans related to limestone burning, masonry stone, granite, limestone crushers and quartz-feldspar from several districts, including Jaipur, Beawar, Sirohi, Baran, Banswara and Churu. "The new system eliminates the need for physical submissions and in-person visits for approvals, benefiting nearly 30,000 leaseholders and quarry license holders of minor minerals," said T Ravikant, principal secretary of mines, geology and petroleum current regulations require mining plans to be approved within 90 days, delays have been common. The digital system aims at resolving such bottlenecks."Leaseholders can now submit applications online, track their status, and receive timely approvals. The fully digital process ensures efficiency, reduces delays, and minimizes inconvenience," said Deepak Tanwar, director of work has begun to establish a Mining Sector Excellence Centre in Jaipur, as announced in the state Budget. Officials said this centre would give mining activities in Rajasthan a much-needed momentum. They highlighted the state's status as India's leading mineral-rich state, with a geological heritage spanning millions of years, including the Archaean, Tertiary, Mesozoic and Aravalli eras. The state has identified 82 types of minerals, including lead-zinc, gold-silver, copper-iron ore and limestone, with 57 being actively new centre will scientifically document and display Rajasthan's mineral wealth, including rare earth elements. Crude oil and natural gas production is also underway. "Mining Sector Excellence Centre will preserve and showcase the state's mining heritage while promoting sustainable, zero-loss mining techniques," said an official.
West Australian
28-04-2025
- Business
- West Australian
$440K govt grant to extend Western Mines Goldfields drilling program
Western Mines Group has been granted two applications under the WA Government's Exploration Incentive Scheme (EIS) for a total of $440,000 to co-fund more drilling at the company's Mulga Tank nickel-copper project in the Eastern Goldfields. Both awards comprise the maximum 50 per cent co-funding available under the government incentive program and were awarded within a competitive application process. WMG will put the funding towards the direct drilling costs of three diamond holes to further test the main body of the company's Mulga Tank complex and an interpreted komatiite channel system that is 8.2 kilometres northwest of the complex. The work will include a 1500-metre deep diamond hole into the Mulga Tank ultramafic complex to follow up results from a previous diamond drilling program and an EIS-funded hole that was drilled last year. The new hole, designated EIS8, will target the eastern portion of a Mobile magneto-telluric anomaly at the base of the intrusion. It will pass close to higher grade geochemical results from a previous diamond hole put into the zone. WMG believes the targeted zone could represent a sulphide-enriched keel and/or a feeder vent for the overall intrusion. The company has also designed two more diamond drill holes to probe to about 700m depth in one of the numerous elongate inferred komatiitic channels in its contiguous exploration licence, about 8.2km northwest of the proposed single deep hole. Komatiite rocks are a type of ultramafic mantle-derived volcanic rock defined as having crystallised from a lava of at least 18 per cent magnesium oxide and containing low silicon, potassium and aluminium and high to extremely high magnesium. The rare rocks almost all formed during the Archaean Eon, between 4.03–2.5 billion years ago, although a few younger examples are known. Geographically, komatiites are mainly distributed to Archaean shield areas – including Mulga Tank for example - and occur with other ultramafic and high-magnesian mafic volcanic rocks in Archaean greenstone belts. WMG first tested the Mulga Tank channel system during a belt-wide reverse circulation drilling program last year. The two new holes will follow up the results of two holes drilled under a previous EIS grant into one of the elongate zones. They will test a body interpreted from aeromagnetic imagery to be about 1.3km long and which drilling confirms as high-magnesium oxide olivine cumulate/dunite and komatiite lithologies, with visible nickel sulphide mineralisation. The planned holes will examine the stratigraphy of the komatiite system and target basal contact that last year's reverse circulation holes did not reach. The company has undertaken various diamond and reverse circulation drilling programs at its Mulga Tank project over the past two years, which have demonstrated significant nickel sulphide mineralisation and an extensive nickel sulphide mineral system within the Mulga Tank ultramafic complex. The company's exploration has included three deep co-funded diamond holes drilled with the aid of its EIS grants in rounds 26 and 28 of the State Government's co-funded exploration drilling program. Previous EIS awards have been instrumental in the discovery of an extensive nickel sulphide mineral system within the Mulga Tank ultramafic complex. The proposed deep EIS hole, EIS8, will look to test the basal contact of the complex and will target the eastern portion of a conductive MobileMT anomaly that was 'grazed' by a non-EIS hole. That hole returned 96m at 0.40 per cent nickel and 0.016 per cent cobalt from 1208m, including 38m at 0.56 per cent nickel and 0.016 per cent cobalt from 1262m, and 8m at 1.11 per cent nickel and 0.018 per cent cobalt from 1270m at a depth corresponding to the MT anomaly. These results are hosted within heavily disseminated sulphide mineralisation that could represent Perseverance-style 'cloud' sulphides occurring near a basal massive sulphide accumulation. WMG has carefully planned a mix of the two drilling methods at Mulga Tank, using reverse circulation rigs to scout and infill previous drilling and then to prove-up the extent of shallow disseminated nickel sulphide mineralisation. The outcome of this work is reflected in the company's giant mineral resource modelling released two weeks ago, containing an eye-watering estimated 5.3 million tonnes of contained nickel, 257,000t cobalt, 161,000t copper and 1.1M ounces combined platinum and palladium. The resource included a stunning combined indicated and inferred total of 1.97 billion tonnes at 0.27 per cent nickel, 131 parts per million (ppm) cobalt, 82ppm copper and 17 parts per billion combined platinum and palladium. WMG's diamond drilling program comprises specific areas of investigation by testing deeper targets for basal massive sulphides potentially hosting nickel, copper and platinum group elements. So far, the company has only drilled the relatively shallow disseminated zone within the more densely drilled parts of its central grid over the complex. Ample space is indicated across the magnetic signature of the central complex area for lateral extensions of this zone. Additionally, the company has only scratched the edge of the possible significance of the multiple north and northwest trending multiple komatiitic feeder/channel system that radiates outwards from the main complex for as much as 15km. And the company has yet to flesh out the extent of the deeper massive sulphide system that may be lurking at depth in or near the keel of the intrusive complex. The next deep hole will help resolve this. Under the terms of the two EIS grants, WMG can kick off drilling of the latest holes from June 1 and the work will be included in its exploration plans for the year. The current nickel price has increased by US$305 (A$478) per tonne since the beginning of the year and is currently US$15,606 (A$24,458) per tonne, offering a great portent for the project's potential. Is your ASX-listed company doing something interesting? Contact:
Yahoo
13-04-2025
- Science
- Yahoo
The Earth's oceans used to be green — and could one day turn purple, scientists say
When you buy through links on our articles, Future and its syndication partners may earn a commission. Nearly three fourths of Earth is covered by oceans, making the planet look like a pale blue dot from space. But Japanese researchers have made a compelling case that Earth's oceans were once green, in a study published in Nature. The reason Earth's oceans may have looked different in the ancient past is to do with their chemistry and the evolution of photosynthesis. As a geology undergraduate student, I was taught about the importance of a type of rock deposit known as the banded iron formation in recording the planet's history. Banded iron formations were deposited in the Archean and Paleoproterozoic eons, roughly between 3.8 and 1.8 billion years ago. Life back then was confined to one cell organisms in the oceans. The continents were a barren landscape of grey, brown and black rocks and sediments. Rain falling on continental rocks dissolved iron which was then carried to the oceans by rivers. Other sources of iron were volcanoes on the ocean floor. This iron will become important later. The Archaean eon was a time when Earth's atmosphere and ocean were devoid of gaseous oxygen, but also when the first organisms to generate energy from sunlight evolved. These organisms used anaerobic photosynthesis, meaning they can do photosynthesis in the absence of oxygen. It triggered important changes as a byproduct of anaerobic photosynthesis is oxygen gas. Oxygen gas bound to iron in seawater. Oxygen only existed as a gas in the atmosphere once the seawater iron could neutralize no more oxygen. Eventually, early photosynthesis led to the "great oxidation event", a major ecological turning point that made complex life on Earth possible. It marked the transition from a largely oxygen free Earth to one with large amounts of oxygen in the ocean and atmosphere. The "bands" of different colors in banded iron formations record this shift with an alternation between deposits of iron deposited in the absence of oxygen and red oxidized iron. The recent paper's case for green oceans in the Archaean eon starts with an observation: waters around the Japanese volcanic island of Iwo Jima have a greenish hue linked to a form of oxidized iron - Fe(III). Blue-green algae thrive in the green waters surrounding the island. Despite their name, blue-green algae are primitive bacteria and not true algae. In the Archaean eon, the ancestors of modern blue-green algae evolved alongside other bacteria that use ferrous iron instead of water as the source of electrons for photosynthesis. This points to high levels of iron in the ocean. Photosynthetic organisms use pigments (mostly chlorophyll) in their cells to transform CO₂ into sugars using the energy of the sun. Chlorophyll gives plants their green color. Blue-green algae are peculiar because they carry the common chlorophyll pigment, but also a second pigment called phycoerythrobilin (PEB). In their paper, the researchers found that genetically engineered modern blue-green algae with PEB grow better in green waters. Although chlorophyll is great for photosynthesis in the spectra of light visible to us, PEB seems to be superior in green-light conditions. Before the rise of photosynthesis and oxygen, Earth's oceans contained dissolved reduced iron (iron deposited in the absence of oxygen). Oxygen released by the rise of photosynthesis in the Archean eon then led to oxidized iron in seawater. The paper's computer simulations also found oxygen released by early photosynthesis led to a high enough concentration of oxidized iron particles to turn the surface water green. Once all iron in the ocean was oxidized, free oxygen (0₂) existed in Earth's oceans and atmosphere. So a major implication of the study is that pale-green dot worlds viewed from space are good candidate planets to harbour early photosynthetic life. Related: A mysterious 'black hole' in Pacific Ocean that sparked wild rumors online The changes in ocean chemistry were gradual. The Archaean period lasted 1.5 billion years. This is more than half of Earth's history. By comparison, the entire history of the rise and evolution of complex life represents about an eighth of Earth's history. Almost certainly, the color of the oceans changed gradually during this period and potentially oscillated. This could explain why blue-green algae evolved both forms of photosynthetic pigments. Chlorophyll is best for white light which is the type of sunlight we have today. Taking advantage of green and white light would have been an evolutionary advantage. The lesson from the recent Japanese paper is that the color of our oceans are linked to water chemistry and the influence of life. We can imagine different ocean colors without borrowing too much from science fiction. Purple oceans would be possible on Earth if the levels of sulphur were high. This could be linked to intense volcanic activity and low oxygen content in the atmosphere, which would lead to the dominance of purple sulphur bacteria. Red oceans are also theoretically possible under intense tropical climates when red oxidized iron forms from the decay of rocks on the land and is carried to the oceans by rivers or winds. Or if a type of algae linked to "red tides" came to dominate the surface oceans. These red algae are common in areas with intense concentration of fertilizer such as nitrogen. In the modern oceans, this tends to happen in coastline close to sewers. RELATED STORIES —Picturesque plankton paint peculiar patterns in Patagonia —Logic-defying 'bottom blooms' could sustain hidden ecosystems in Arctic and Antarctica —Billion-year-old green algae is an ancestor of all plants on Earth As our sun ages, it will first become brighter leading to increased surface evaporation and intense UV light. This may favor purple sulphur bacteria living in deep waters without oxygen. It will lead to more purple, brown, or green hues in coastal or stratified areas, with less deep blue color in water as phytoplankton decline. Eventually, oceans will evaporate completely as the sun expands to encompass the orbit of Earth. At geological timescales nothing is permanent and changes in the color of our oceans are therefore inevitable. This edited article is republished from The Conversation under a Creative Commons license. Read the original article.
Yahoo
12-03-2025
- Science
- Yahoo
Earth's Oldest Crater May Have Jumpstarted All Life
"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." Geologists have now unearthed evidence of a 3.5 billion-year-old crater found in a layer of Australian rock. Shatter cones, which are features caused by the shockwave of a hypervelocity meteorite impact, are evidence that something hit this region when Earth was young. Impact craters this old have the potential to tell us not only how Earth evolved but how the earliest impacts created the conditions for life to emerge. Long before the asteroid that ended the dinosaurs crashed to Earth, our planet was being bombarded by space rocks that left behind enormous craters. The reign of T. rex and Co. ended around a measly 66 million years ago, but geologists just discovered that what is now considered the oldest impact crater on Earth is nearly 3.5 billion years old. Earth itself formed only a billion years prior to an ancient collision that slammed what is now Australia. The earliest known fossils of single-celled organisms date from around the time the crater was formed, the Archaean era, which overlapped with the end of the Late Heavy Bombardment. It is thought, that during this epoch, a disruption in planetary orbits threw asteroids from the asteroid belt towards the planets of the inner Solar System. Lunar craters that are relics of the Late Heavy Bombardment are mostly obvious, since the Moon has hardly any weather phenomena (because of the lack of atmosphere), no plate tectonics, no liquid water, and no life. These craters are much more difficult to find on Earth. Eons of erosion and shifting of continents may have buried them and possibly erased them, which is why they are so rare, but not only can we add this new one to our list, but it's the oldest one we've ever found. Led by Curtin University geologists Chris Kirkland and Tim Johnson, a research team unearthed this primeval crater beneath rock layers in the East Pilbara Terrane of Western Australia. The oldest Archaean crater before this discovery went back only 2.2 billion years. 'On Earth, this early impact record has seemingly been lost, reflecting the destructive efficiency of erosion and subduction in recycling primary (basaltic, oceanic) crust back into the convecting mantle,' Kirkland and Johnson said in a study recently published in Nature Communications. Meteorite impacts are said to have triggered plate tectonics and volcanic activity on a young Earth, forming cratons, or huge chunks of crust that were the beginnings of the continents. Part of the Pilbara Craton, the East Pilbara Terrane is a nearly pristine fragment of crust around 200 km (124 miles) in diameter. The crater was unearthed near the center of this region and identified by shatter cones and spherules. These features, found in a 3.5 billion-year-old layer of silicate rocks mashed up with older rocks, suggest at least two Archaean impacts. When a meteorite hits the surface, shock waves from the impact propagate through layers of rock, cracking the rock in such a way that creates cone formations. The ridges left in these shatter cones capture a permanent reminder of the shockwave. Particles of melted and re-solidified rock (spherules) were kicked up by the impact and fell onto the surrounding area. Whether the spherules found at East Pilbara Terrane have a cosmic or terrestrial origin is debatable, but they are still evidence that something plummeted through the atmosphere and crashed to Earth. Whatever hit Australia billions of years ago possibly did more than just leave an enormous scar. Meteorite impacts might have made it possible for life to survive. Some of the oldest fossils of microbial life are close in age or just slightly older than the Pilbara crater. 'Impact craters may have provided the physical and chemical environments required for life to emerge on Earth and elsewhere,' the researchers said in the same study. Could that 'elsewhere' have been Mars? There is no evidence yet, but NASA's Perseverance rover keeps searching as it crawls across the barren expanse of Jezero Crater, which used to be an ancient crater lake that has long since dried up. Finding more of the most ancient craters on Earth might tell us something about Archaean remnants beyond our planet. You Might Also Like Can Apple Cider Vinegar Lead to Weight Loss? Bobbi Brown Shares Her Top Face-Transforming Makeup Tips for Women Over 50
