Explained Snippets | This Word Means — Earthquake Swarms

Quakes in Indonesia represent a kind of seismic activity that is different from the one seen in Nepal in 2015

By: Express News Service | Updated: August 23, 2018 8:59:05 am
Quakes in Indonesia represent a kind of seismic activity that is different from the one seen in Nepal in 2015 People walk on a road damaged by yesterday’s large earthquake at Kayangan Port in Lombok, Indonesia.

On Sunday, two weeks after the August 5 earthquake that left at least 480 people dead in Indonesia, the region was hit by another earthquake of the same magnitude (6.9 on the Richter scale), and having the same epicentre (the holiday island of Lombok to the east of Bali). Four significant quakes were recorded that day — the first, measuring 6.3 on the Richter scale, struck shortly before midday; it was followed 12 hours later by another measuring 6.9, and subsequently by two more, of strength 5.9 and 5.3 on the Richter scale.

Indeed, a series of temblors have hit the Indonesian archipelago since July 29. They have been of similar scale and, even though the August 5 event extracted the largest death toll, there has not been a discernible ‘main’ shock. Seismologists describe such a phenomenon as an “earthquake swarm”. According to the Swiss Seismological Service, swarms are made up of numerous earthquakes that occur locally over an extended period, without a clear sequence of high-intensity main quakes, preceded and succeeded by lower-intensity foreshocks and aftershocks.

An earthquake swarm can last for weeks, and the pace of subsidence is gradual, relative to aftershocks in normal earthquakes. Swarms are observed in volcanic environments, hydrothermal systems, and other active geothermal areas, according to geophysicists. While the April 2015 Nepal earthquake demonstrated the foreshocks-main shock (7.8)- aftershocks trend, the seismic activity in Indonesia fits the typology of the swarm.

— SUDHAKAR JAGDISH

Telling Numbers — Education loans up 20%, but sector NPAs rising steadily

Education loans disbursed by Scheduled Commercial Banks (SCBs) crossed Rs 14,700 crore in the last financial year. This represented a growth of 20.5% over 2016-17, Parliament was told earlier this month. Disbursals in 2016-17, however, showed a negative growth of 9% over the previous year, 2015-16. Overall, in the four years since 2014-15, education loans have grown nearly 50% from Rs 10,000 crore.

Significantly, bad loans in the education sector have also been rising over the past three years, with NPAs nearing 9% of the outstanding by March 2018, according to data reported this month. Banks follow the Indian Banks Association’s (IBA’s) model education loan scheme while disbursing loans, which provides for a repayment period of up to 15 years. IBA data show the percentage of NPAs to outstanding education loans rose from 7.3% in March 2016 to 7.67% the following March, and to 8.97% in March 2018. The outstanding education loan amount at the end of 2017-18 was Rs 71,724.65 crore, of which Rs 6,434.62 crore were NPAs.

Public sector banks began to disburse education loans in 2000-01. The rise in bad loans has been attributed to the fact that many students are not getting jobs, or getting jobs that don’t pay enough, as well as to overcapacity created in education as engineering and management colleges mushroomed.

Tip for Reading List — Something Fishy About Omega-3

The American marine conservationist Paul Greenberg knows his fish, having written two books, Four Fish: The Future of the Last Wild Food, and American Catch: The Fight for our Local Seafood, before his latest, also on fish — The Omega Principle: Seafood and the Quest for a Long Life and a Healthier Planet — that was published last month. It challenges the widely revered cult of the omega-3 fatty acids — besides telling, as Dr Siddhartha Mukherjee, author of The Emperor of All Maladies: A Biography of Cancer, and The Gene: An Intimate History, says, “the story of supplements, dietary fads, quackery, and the future of human health”.

What is omega-3? What does it actually do in the body? Greenberg’s book questions commonly-held ideas that fish oils may help prevent coronary heart disease, increase brain volume, boost sperm competitiveness, prevent depression, and lower the risk of diabetes — bases for the existence of the multi-billion dollar omega-3 industry, which is thought to be rooted in Danish research that found low cardiac death rates among people who had more omega-3s in their blood. The “golden pills” in fact, do not have any effect on the human body, Greenberg says.

Also, “If you were to take out all the fish of the world, boil them down, and produce the necessary pills to supplement the word’s anticipated 9 billion humans… the ocean would have been mercilessly raided”. The omega oil that is used in the supplements is not a byproduct of fish that are being processed for human consumption — rather, it is siphoned off from boiled-down forage fish that are pulled out of the ocean, in a quantity “equivalent to the human weight of the United States every year”, just for this purpose.

— TANNU JAIN

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