Sollasina cthulhu: A new species of Ophiocistioid Echinoderm from the Silurian Herefordshire Lagerstätte.

The living Echinoderm groups Echinoidea (Sea Urchins) and Holothuroidea (Sea Cucumbers) are united into the larger group Echinozoa, allong with an extinct group, the Ophiocistioidea, which first appeared in the Ordovician and died out in the Triassic. The Ophiocistioids shared some traits seem in modern Echinozoans, such as complex jaw apparatus of the Sea Urchins and the body-wall skeleton mostly reduced to small spicules of the Sea Cucumbers, with traits uniquely their own, most notably a dome-shaped body similar to half the test of a Sea Urchin, with five ambulacra on the outside, radiating out from a mouth at the centre, each of which ends with three enlarged, tentacle-like tube feet. Because of the easily fragmented nature of the skeletons of these Echinoderms, they are only found in deposits with exceptional preservation.

In a paper published in the journal Proceedings of the Royal Society Series B Biological Sciences on 10 April 2019, Imran Rahman of the Oxford University Museum of Natural History, Jeffrey Thompson of the Department of Earth Sciences at the University of Southern California, Derek Briggs of the Department of Geology and Geophysics and Yale Peabody Museum of Natural History at Yale University, David Siveter of the School of Geography, Geology and the Environment, at the University of Leicester, Derek Siveter also of the Oxford University Museum of Natural History, and of the Department of Earth Sciences at the University of Oxford, and Mark Sutton of the Department of Earth Sciences and Engineering at Imperial College London, describe a new species of Ophiocistioid Echinoderm from the Silurian Herefordshire Lagerstätte of England.

The Herefordshire Lagerstätte comprises a large number of small (at most centimetres) organisms from the Middle Silurian (about 425 million years ago). The organisms are preserved in three dimensions within calcareous nodules within a layer of volcaniclastic sediments (i.e. a volcanic ashfall in a marine environment), many of which can only be accessed using computerised tomography or similar scanning techniques. Brachioods, Polychaete Worms, Gastropods, Aplacophorans, Chelicerates, Marrellomorphs, Mandibulates, Barnacles, Phyllocarids, Ostracods, Starfish and Sponges have all been found in the Herefordshire Lagerstätte; together these are known as the Herefordshire Biota.

The new species is placed in the genus Sollasina, and given the specific name cthulhu, in reference to the tentacled monster from the writings of HP Lovecraft. The species is described from thirteen fossils, all preserved three-dimensionally as calcite void-fill in calcareous concretions. One exceptionally well-preserved specimen was selected for detailed study by physical–optical tomography. The specimen was cut into seven pieces, serially ground at 30 μm intervals, and the exposed surfaces were imaged using a Leica digital camera attached to a Wild binocular microscope. The resulting sets of slice images were digitally reconstructed as a three-dimensional (3-D) virtual model using the SPIERS software suite.

Sollasina cthulhu. (a)–(m) Virtual reconstructions (stereo-pairs), (n), (o) specimen in rock. (a) Oral view. (b) Lateral view. (c) Aboral view. (d) Non-peristomial tube foot (unpaired). (e) Non-peristomial tube foot (paired). (f) Peristomial tube feet. (g) Oral view showing the peristome, madreporite and gonopore (peristomial tube feet omitted). (h) Oral view showing the madreporite and gonopore (peristomial tube feet removed). (i) Aboral view showing the periproct. (j) Lateral view showing plating in the interambulacral area containing the madreporite and gonopore (tube feet removed). Interambulacral plates are shown in green. (k) Oral view showing ambulacral plating at the margin of the theca (tube feet removed). (l) Oral view showing the internal ring (all other features transparent). (m) Aboral view showing ambulacral plating at the margin of the theca (tube feet removed). (n) Section through the theca showing the tube feet. (o) Section through the theca showing the internal ring. Abbreviations: cp, circular pore; go, gonopore; ir, internal ring; jp, jaw plates; ma, madreporite; pe, peristome; pr, periproct; pt, peristomial tube feet; st, small adoral non-peristomial tube foot; tf, non-peristomial tube feet; ut, unpaired non-peristomial tube feet. In k and m, perradial plates are shown in purple, adradial plates in red, and interambulacral plates in green. Scale bars: (a)-(c), (l ) 5 mm; (d), (e), (g), (k), (l), (n), (o) 2 mm; (f), (h), (i), (j), (m) 1 mm. Rahman et al. (2019).

Sollasina cthulhu has a theca approximately 15 mm in diameter and pentagonal in outline, with thin, imbricate plates. The oral (lower) surface is slightly concave; the aboral (upper) surface is partly collapsed, but was presumably convex in life. The oral surface of the theca consists of five wide ambulacral areas, composed of columns of perradial and adradial plates, which alternate with five narrow interambulacral areas. The aboral surface of the theca consists of numerous irregularly arranged plates. The peristome occupies the middle of the oral surface. It is subcircular in outline and approximately 6 mm in diameter. Five thick, rhomboidal, interradially positioned plates form the jaw apparatus, which occupies about half the peristome diameter. 

In each ambulacral area, the plates are divided into one central column of six alternating perradial plates and two lateral columns of four adradial plates each. There are nine plated tube feet within each ambulacral area. The first pair is located within the peristome, close to the outer edge of the jaw apparatus. These peristomial tube feet are covered in tiny plates and are smaller than the other tube feet, measuring approximately 3 mm in length and 0.8 mm in diameter. The other tube feet are located outside the peristome, occurring as three slightly offset pairs, with an additional solitary tube foot at the aboral end of each ambulacral area. The non-peristomial tube feet increase in size aborally (reaching a maximum of approximately 14 mm in length and 2 mm in diameter), with the exception of the unpaired tube foot which is shorter than its adoral neighbour. Within one of the ambulacral areas, the most adoral of the tube feet outside the peristome is much smaller than all others . The tube feet are preserved hollow. They consist of thin plates arranged in longitudinal rows, overlapping distally. There are at least eight rows of about 20–30 plates each in the paired tube feet and four rows of about 13 plates each in the unpaired ones.

Reconstruction of Sollasina cthulhu. Elissa Martin/Division of Invertebrate Paleontology/Yale Peabody Museum of Natural History in Rahman et al. (2019).

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Landslide kills father and son in Maharashtra State, India.

Two people have died after a landslide destroyed their home in Thane in northern Maharashtra State, India, on Tuesday 30 July 2019. Birendra Jaswal, 40 and his son Sunny Jaswar, 10, were sleeping in the building when part of a hillslope collapsed onto it. They were rushed to the Chatrapati Shivaji Hospital in Kalwa for treatment, but both died of their injuries. Jaswar’s wife Neelam, 35, was also injured and is being treated in the hospital, where her condition is described as 'stable'/ Local authorities have evacuated another nineteen families from fifteen nearby homes, which they describe as having been built illegally by unscrupulous landlords on the flanks of Parsik Hill, which is notoriously unstable following years of illegal quarrying and deforestation. The evacuated families are being housed temporarily at a nearby school while the properties are demolished. What long term plans the authorities have for rehousing them are unclear.

The aftermath of a landslide on the side of Parsik Hill in Thane that killed two people. Hindustan Times.

The area where the incident occurred is known to suffer a high risk of landslides, particularly during the  monsoon season when high rainfall frequently triggers such events. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. To this end the slopes above the expressway had been re-enforced against such events. However local press sources are reporting that these defences are largely iron in construction, and in places are showing signs of severe corrosion.

Maharashtra State has a monsoon climate, with the rains typically arriving around the start of June and peaking in July. The area where the 19 July 2015 landslip occurred typically receives over 500 mm of rain in June and over 1300 mm in July, and the area suffers frequent landslip and flooding events. This situation is made worse by widespread deforestation and quarrying for construction materials (much of it illegal) which tends to destabilise hill slopes.

Monsoons are tropical sea breezes triggered by heating of the land during the warmer part of the year (summer). Both the land and sea are warmed by the Sun, but the land has a lower ability to absorb heat, radiating it back so that the air above landmasses becomes significantly warmer than that over the sea, causing the air above the land to rise and drawing in water from over the sea; since this has also been warmed it carries a high evaporated water content, and brings with it heavy rainfall. In the tropical dry season the situation is reversed, as the air over the land cools more rapidly with the seasons, leading to warmer air over the sea, and thus breezes moving from the shore to the sea (where air is rising more rapidly) and a drying of the climate. This situation is particularly intense in South Asia, due to the presence of the Himalayas. High mountain ranges tend to force winds hitting them upwards, which amplifies the South Asian Summer Monsoon, with higher winds leading to more upward air movement, thus drawing in further air from the sea. 

 Diagrammatic representation of wind and rainfall patterns in a tropical monsoon climate. Geosciences/University of Arizona.

  

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Parsik hills

Read more at:
http://timesofindia.indiatimes.com/articleshow/70460239.cms?utm_source=contentofinterest&utm_medium=text&utm_campaign=cppst

Communities gather meat after Whale washes up on beach in Bayelsa State, Nigeria.

Members of local communities across the Brass Local Government Area of Bayelsa State, Nigeria, have been rushing to a beach near the communities of Ijaw-Kiri, Odioma, and Okpoama after a dead Whale was found there on Sunday 28 June 2019. The Ijaw people of the area do not traditionally hunt Whales, but do consume Whale meat from animals found dead on or near the shore. On this occasion the animal has widely been viewed as a gift from God, sent to help the people during a time of food shortages, following recent poor Fish catches in the area. The last time such a Whale was found in the area was in 2017, and the time before that in 1983.

Local people harvesting meat from a Whale which washed up in the Brass Local Government Area of Bayelsa State, Nigeria, on Sunday 28 July 2019. Ebi Johnson/BBC.

Although local people have viewed the arrival of the Whale as an act of providence, officials from the National Agency for Food, Drug Administration and Control have warned that there can be health risks associated with the consumption of meat obtained in such a way. A number of toxins can accumulate in the meat of Whales, including polychlorinated biphenyls (persistent organic compounds used in a variety of industrial processes), pesticides, and methyl mercury. Such toxins are of particular concern in a Whale that has died of unknown causes, as it might itself have been poisoned by a build up of such bioaccumulative toxins. The agency has warned that pregnant women and small children are at greater risk from such toxins.

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Asteroid 2019 OD passes the Earth.

Asteroid 2019 OD  passed by the Earth at a distance of about 357 840 km (0.93 times the average distance between the Earth and the Moon, or 0.24% of the distance between the Earth and the Sun), slightly after 1.30 pm GMT on Wednesday 24 July 2019. There was no danger of the asteroid hitting us, though were it to do so it would have presented a significant threat. 2019 OD has an estimated equivalent diameter of 38-120 m (i.e. it is estimated that a spherical object with the same volume would be 38-120 m in diameter), and an object at the upper end of this range would be predicted to be capable of passing through the Earth's atmosphere relatively intact, impacting the ground directly with an explosion that would be about 20 000 times as powerful as the Hiroshima bomb. Such an impact would result in an impact crater over 1.5 km in diameter and devastation on a global scale, as well as climatic effects that would last years or even decades.

 Close approach of Asteroid 2019 OD to the Earth on 24 July 2019.  The green line indicates the object's apparent motion relative to the Earth, and the bright green marks are the object's location at approximately half hour intervals. The Moon's orbit is grey. The blue arrow points in the direction of Earth's motion and the yellow arrow points toward the Sun. Minor Planet Center.

2019 OD was discovered on 21 July 2019 (three days before its closest approach to the Earth) by the Atlas MLO Telescope at Mauna Loa Observatory in Hawaii. The designation 2019 OD implies that the asteroid was the fourth object (object D - in numbering asteroids the letters A-Z, excluding I, are assigned numbers from 1 to 25, so that D = 4) discovered in the second half of July 2019 (period 2019 O).

2019 OD has an 1347 day orbital period and an eccentric orbit tilted at an angle of 0.82° to the plane of the Solar System, which takes it from 0.68 AU from the Sun (i.e. 68% of he average distance at which the Earth orbits the Sun, and slightly inside the orbit of the planet Venus) to 4.09 AU from the Sun (i.e. 409% of the average distance at which the Earth orbits the Sun, and somewhat more than twice the orbit of the planet Mars). It is therefore classed as an Apollo Group Asteroid (an asteroid that is on average further from the Sun than the Earth, but which does get closer). This means that close encounters between the asteroid and Earth are common, with the last having occurred in July 2008 and the next predicted in August 2020

The calculated orbit of 2019 OD. JPL Small Body Database.

2010 OD also has frequent close encounters with the planets Venus, which it last came close to in February 1946 and is  next predicted to pass in April 2056, Mars, which it is predicted to pass again in May 2038, and Jupiter, which it last came close to in August 2017 and is next predicted to pass in December 2028. Asteroids which make close passes to multiple planets are considered to be in unstable orbits, and are often eventually knocked out of these orbits by these encounters, either being knocked onto a new, more stable orbit, dropped into the Sun, knocked out of the Solar System or occasionally colliding with a planet.

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Landslide kills at least nineteen at Myanmar jade mine.

Nineteen people have now been confirmed dead following a landslide at a jade mine at Seikhmu near Hpakant in Kachin State, Myanmar, on Sunday 28 July 2019. The incident happened at about 2.30 in the morning local time, at a concession operated by the Yarzahtarni Jade Mining Company, and swept through an encampment where workers at the mine were sleeping, with several of those killed thought to have been security guards rather than miners. 

Rescue workers at the scene of a landslide at a jade mine in Kachin State, Myanmar, on 28 July 2019. Thinkhar Civil Society.

Myanmar is the world's largest producer of jade, though much of this is produced (along with other precious and semi-precious minerals such as amber) at unregulated (and often illegal) artisanal mines in the north of the country, from where it is smuggled into neighbouring China. Accidents at such mines are extremely common, due to the more-or-less total absence of any safety precautions at the site. At many sites this is made worse by the unregulated use of explosives to break up rocks, often leading to the weakening of rock faces, which can then collapse without warning. The majority of people in this industry are migrant workers from the surrounding countryside, not registered with any local authority, which can make it difficult for rescuers to identify victims following such events, or even gain accurate assessments of the number of people likely to have been involved in such accidents.

The incident occurred following several hours of rain in the area associated with the Southeast Asian Southwest Monsoon, which has also caused a series of landslips and flash floods in the area. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. This year's monsoon has been particularly severe, with floods and landslips occurring across Myanmar.

Monsoons are tropical sea breezes triggered by heating of the land during the warmer part of the year (summer). Both the land and sea are warmed by the Sun, but the land has a lower ability to absorb heat, radiating it back so that the air above landmasses becomes significantly warmer than that over the sea, causing the air above the land to rise and drawing in water from over the sea; since this has also been warmed it carries a high evaporated water content, and brings with it heavy rainfall. In the tropical dry season the situation is reversed, as the air over the land cools more rapidly with the seasons, leading to warmer air over the sea, and thus breezes moving from the shore to the sea (where air is rising more rapidly) and a drying of the climate.

 Diagrammatic representation of wind and rainfall patterns in a tropical monsoon climate. Geosciences/University of Arizona.

  

Much of Southeast Asia has two distinct Monsoon Seasons, with a Northeast Monsoon driven by winds from  the South China Sea that lasts from November to February and a Southwest Monsoon driven by winds from the southern Indian Ocean from March to October. Such a double Monsoon Season is common close to the equator, where the Sun is highest overhead around the equinoxes and lowest on the horizons around the solstices, making the solstices the coolest part of the year and the equinoxes the hottest. However Myanmar is largely protected from the Northeast Monsoon by the mountains separating the country from Yunnan Province in China.

 

The winds that drive the Northeast and Southwest Monsoons in Southeast Asia. Mynewshub.

 

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