Translate

Monday, September 19, 2022

The Brunswick Magnetic Anomaly

 


The Brunswick Magnetic Anomaly is a belt of volcanic rocks that formed around 200 million years ago at the time when the Atlantic Ocean took shape. The ribbon of rock is buried about 9 to 12 miles below the surface. It snakes from Alabama across Georgia, and offshore to North Carolina's Outer Banks.

It is believed that the Brunswick Magnetic Anomaly was created when the crusts of Africa and North America were yanked apart. As North America broke from Pangaea, deep troughs formed along the line of separation. These troughs filled with thick layers of coarse red sandstones, conglomerates, shales, and other nonmarine sediments. Similar sediment-filled troughs (called "rift valleys") occurred along North America’s east coast, from Georgia to Nova Scotia, Canada.

Though North America's east coast is relatively quiet now, clues to these ancient tectonic collisions remain buried deep underground. Using special instruments, geophysicists can discover important information about the large-scale motion of Earth’s outermost shell by determining the source of distinct striped magnetic anomalies.

The Brunswick Magnetic Anomaly may mark the original collision zone between the African and North American plates. At least part of this belt of volcanic rock may represent a suture between the plates east of Georgia. 



Friday, September 2, 2022

Counting and Measuring Tree Rings

 


Dendrochronology is the science of dating events such as volcanic eruptions, forest fires, and environmental changes by studying the characteristic patterns of annual growth rings in timber and tree trunks. Tree cell anatomy contributes to a better understanding of past climate events.

Irina Panyushkina pioneered one of the earliest wood anatomy studies in 1998.She spent the late ’90s in Krasnoyarsk at the Russian Academy of Sciences hunched over a microscope, peering down at paper-thin slices of wood from Arctic larch trees.

Panyushkina painstakingly counted and measured thousands of wood cells to create a 350-year climate chronology, dating from 1642 to 1993. It was among the most rigorous tree-ring–based reconstructions of past climate at the time, but it was also prohibitively tedious. To image the cells, each thin section first had to be photographed under a microscope, and then the images were imported into a computer and displayed onscreen. Panyushkina then had to click on every cell to tell the program to measure it.

Panyushkina took 9,460 photographs from 1,896 tree rings, in just 11 tree samples. The work took her four years. “It was so intensive and laborious,” says Panyushkina, who’s now at the Laboratory of Tree-Ring Research at the University of Arizona. “I said I’ll never do it again.

Fortunately, since Panyushkina's research there have been significant advances in dendrochronology and paleoclimate research because of analytical software and computing power. What would have taken weeks in the ’90s now takes days, says Jesper Björklund at the Swiss Federal Research Institute in Birmensdorf. “Using the same amount of time you can obtain roughly 100 times more data, increasing the potential for robustness and scope of each study,” he says. 

The “big jump,” Björklund says, was the development of a software called ROXAS in the early 2000s, which identifies and measures cells from high-resolution scans of tree rings.

Read more here.

Related reading: Tree Story by Valerie Trouet, Johns Hopkins University, 2020


Friday, August 26, 2022

The Chibanian Age of Geologic Time

 

Schematic illustration of Earth's magnetic field.
Credits: Peter Reid, The University of Edinburgh


A geomagnetic reversal is a change in a planet's magnetic field such that the positions of magnetic north and magnetic south are interchanged.

About 770,000 years ago, Earth’s magnetic fields reversed, swapping magnetic north and south for the last known time. That ushered in a new geological age which scientists have now named the Chibanian.

The Chibanian age is named after the Japanese prefecture Chiba where a cliff wall was found with an exposed layer of marine deposits and mineral debris about 770,000 years old.

When geologists studied the minerals inside, they found evidence of the last known shifting of Earth’s magnetic fields. The planet’s outer core generates its magnetic field, a kind of shield that protects Earth from solar wind.

As molten rock cools, iron-bearing minerals form. They align themselves with the magnetic field, then solidify, acting as a kind of snapshot of Earth’s magnetic field at the time cooling occurred.

The minerals in Chiba allowed geologists to date the last known switch of magnetic fields to about 774,000 years ago. They named the reversal event the Brunhes-Matuyama reversal in honor of the French geophysicist Bernard Brunhes (1867-1910) and the Japanese geophysicist Motonori Matuyama (1884-1958).

Matuyama was the first to provide systematic evidence that the Earth's magnetic field had been reversed in the early Pleistocene and to suggest that long periods existed in the past in which the polarity was reversed.

Antoine Joseph Bernard Brunhes was a pioneer in paleomagnetism. His 1906 discovery of geomagnetic reversal has since been verified. The current period of normal polarity, called Brunhes Chron, is named for him.

Tuesday, July 19, 2022

The 2022 American Scientific Affiliation Annual Meeting

 

Tell your friends and join the meeting.

https://www.youtube.com/watch?v=WtyvKEhf8kY



Plenary I: "Reductionism, Emergence, and Free Will: Are We Bound by the Laws of Physics?" on July 29.



Plenary II: "The Scientist and the Questions of Race and Justice." Don't miss his workshop either, "Key Advances in the Science of Adam, Eve, and Evolution" on July 30.



Plenary III: "Mathematics for Human Flourishing" on July 31.



Plenary IV: "Flourishing Future: Keeping God's Creation "Good" So All Can Thrive" on August 1.





Monday, June 27, 2022

James Clerk Maxwell: A Man of Faith


James Clerk Maxwell
1831-1879


James Clerk Maxwell was a Scottish mathematician and scientist responsible for the classical theory of electromagnetic radiation, the first theory to describe electricity, magnetism and light as different manifestations of the same phenomenon. He also made fundamental contributions to mathematics, astronomy and engineering.

He was a strong Christian and one of Einstein's heroes. Albert Einstein said, "One scientific epoch ended and another began with James Clerk Maxwell."

"The special theory of relativity owes its origins to Maxwell's equations of the electromagnetic field."


From an early age, James Clerk Maxwell had an astonishing memory and an unquenchable curiosity about how things worked. His first teacher, his mother, encouraged him to "look up through Nature to Nature's God."

Campbell, L. and W. Garnett. 1882. The Life of James Clerk Maxwell: With Selections from His Correspondence and Occasional Writings. London: Macmillan and Co. reports on p. 32:
His knowledge of Scripture, from his earliest boyhood, was extraordinarily extensive and minute.... These things were not known merely by rote. They occupied his imagination and sank deeper than anybody knew.

 

Maxwell is held in high regard by the scientific community, but few acknowledge his Christian faith or his conviction in the authority of God's Word. Virtually every part of his brief, but remarkable, life was spent exploring the wonder of God's creation.



Saturday, June 4, 2022

Newly Predicted Superhard Carbon Structures

 



An illustration depicts three of 43 newly predicted superhard carbon structures. The cages colored in blue are structurally related to diamond, and the cages colored in yellow and green are structurally related to lonsdaleite. Credit: Bob Wilder / University at Buffalo


Researchers have used computational techniques to identify 43 previously unknown forms of carbon that are thought to be stable and superhard -- including several predicted to be slightly harder than or nearly as hard as diamonds. Each new carbon variety consists of carbon atoms arranged in a distinct pattern in a crystal lattice.

The study -- published in the journal npj Computational Materials -- combines computational predictions of crystal structures with machine learning to hunt for novel materials. The work is theoretical research, meaning that scientists have predicted the new carbon structures but have not created them yet.

Eva Zurek, a University at Buffalo professor of chemistry, conceived of the study and co-led the project with Stefano Curtarolo, PhD, professor of mechanical engineering and materials science at Duke University.

Superhard materials can slice, drill and polish other objects. They also hold potential for creating scratch-resistant coatings that could help keep expensive equipment safe from damage.

"Diamonds are right now the hardest material that is commercially available, but they are very expensive," says Zurek. "I have colleagues who do high-pressure experiments in the lab, squeezing materials between diamonds, and they complain about how expensive it is when the diamonds break.

She added, "We would like to find something harder than a diamond. If you could find other materials that are hard, potentially you could make them cheaper. They might also have useful properties that diamonds don't have. Maybe they will interact differently with heat or electricity, for example."

The first and second authors of the new study are UB PhD graduate Patrick Avery and UB PhD student Xiaoyu Wang, both in Zurek's lab. In addition to these researchers, Zurek, Curtarolo and Toher, the co-authors of the paper include Corey Oses and Eric Gossett of Duke University and Davide Proserpio of the Universitá degi Studi di Milano.

The research was funded by the U.S. Office of Naval Research, with additional support from the Universitá degi Studi di Milano, and computational support from UB's Center for Computational Research.

Read more here and here.



Monday, May 9, 2022

Seawater to Drinking Water

 




MIT researchers have developed a suitcase-sized portable desalination unit that can remove particles and salts to render drinking water that exceeds World Health Organization quality standards. The device runs with the push of one button and requires less power to operate than a cell phone charger. It also can be charged by solar power.

Unlike other portable desalination units that require water to pass through filters, this device utilizes electrical power to remove particles from drinking water. Eliminating the need for replacement filters greatly reduces the long-term maintenance requirements.

The unit relies on ion concentration polarization (ICP). Rather than filtering water, the ICP process applies an electrical field to membranes placed above and below a channel of water. The membranes repel positively or negatively charged particles — including salt molecules, bacteria, and viruses — as they flow past. The charged particles are funneled into a second stream of water that is eventually discharged.

The researchers also created a smartphone app that can control the unit wirelessly and report real-time data on power consumption and water salinity.

This unit could be deployed in remote and severely resource-limited areas, such as communities on small islands or aboard seafaring cargo ships. It also could be used to aid refugees or by soldiers carrying out long-term military operations.

Read more here and here.