Pillow Basalt lava structures of Karnataka

Pillow Basalt - A feature seen today forming only in oceans along active rift margins or submarine volcanoes. But the Pillow basalt lava structures of Karnataka are far away from any active submarine volcanoes or mid-oceanic ridges (see the white down arrow showing the location of Pillow basalt far away from any active submarine volcano vents or oceanic ridges). 

Position of Mardahalli Pillow basalt w.r.t to the active Andaman Sea Back-Arc Basin (BAB) in the east and mid-oceanic Carlsberg ridge (diverging spreading center) in the south west.  (Image courtesy: Google Earth)

They were formed ~2.8 billion years ago, and provides an important clue to the evolution of precambrian peninsular India. I visited the site during my masters study in 2009, and this small mound hosts an important clue to submarine volcanic activity of Peninsular India during the Precambrian times. 

You might be wondering how does it look like? They look like buns or pillows - a feature formed when hot molten basaltic magma slowly erupts under water and solidifies so rapidly to form roughly spherical or rounded pillow-shape. Such pillow basalts can be seen forming even today along the mid-oceanic ridges or where sub-marine volcano erupts in the ocean. The lava gets chilled so fast that part of the flow separates into discrete rounded bodies a few feet or less in size. The pillow basalts when erupted under water forms a chilled rind on all sides of the extrusion. 

Features of pillow structure - rind, vesicle zone and core seen on pillow lava cliff section at Mardihalli hill (marker pen for scale). (Photo by: R. Thomas)

The hot rind is solid but elastic (like a balloon), and continuous injection of lava into it leads to bulbous, spherical, or tubular lobes that eventually solidify to form pillow-shaped masses of basalt. Have a look at the video of pillow lava formation.

The pillow lavas structures of Mardihalli hill in Karnataka is one of the featured national geological monument on the Geological Survey of India website. It is located near Maradihalli, a small village situated in Chitradurga District, Karnataka. But not many know about it or is not part of the travel itineraries of many tourist. It is nestled within Chitradurga schist belt of Dharwar Group and is one of the best preserved of its kind in the world. However, there is another similar pillow lava monument located in the Iron ore belt of Nomira, Keonjhar District, Odisha. To get there is very easy, it can be approached by a metalled road via Ayamangala which is about 180 km from Bangalore. Maradihalli is 16 km southeast of Chitradurga town and 4 km north of Ayamangala village, along the NH-4 (Bangalore –Pune).

Pillow lava location just south of Maradihalli village. (Image courtesy: Google Earth)

The visit to the site was part of geological mapping study exercise together with Geological survey of India. What I remember so fondly is standing beside this cliff with my chisel end hammer, and being carried away in the geological past, imagining the under sea eruption. But what has made this moment come alive once again is the paper by Duraiswami et. al. published last year in the Journal of Volcanology and Geothermal Research on the 'Emplacement of pillow lavas from the ~2.8 Ga Chitradurga Greenstone Belt, South India: A physical volcanological, morphometric and geochemical perspective'. 

Stacked pillow lava structure at Mardihalli hill- a national Geological Monument. (Hammer for scale)  (Photo by: R. Thomas)

How were they placed there? The research article attributes its placement to marginal shallow marine inter/ back arc basin. The study also shows repeated budding of larger pillows, producing a series of interconnected pillow units indicating fluid lava that was emplaced on steeply dipping flanks. 

Budding (indicated by black arrow) of a pillow lava /basalt at Mardihalli hill. (Photo by: R. Thomas)

The study was also carried on another hill along the road northwest of Mardihalli near Kunchiganalu marked as Chitradurga hill in the literature, which shows individual pillowed flows alternating with massive submarine sheet flows that are devoid of any vesicles (I did not visit this one). Both Mardihalli and Chitradurga hills are part of the north-south trending hills of the Chitradurga greenstone belt that mimics a back arc submarine basin. The main outcomes of the study of the pillow lavas shows - they were emplaced at low to moderate effusion rates (≤ 5 m3/s), and erupted as tholeiites (not as andesites as previously interpreted). The study shows Back Arc-Basin affinities based on the geochemistry, and envisages that the Chitradurga basin witnessed distinct episodes of submarine tholeiite eruptions that produced pillowed lavas, that later variably interacted with sea water to produce spilitized geochemistries. The field and stratigraphic relationships of the volcanics and associated clastic sediments suggest that the pillow lavas were emplaced in a shallow marine marginal inter/back arc basin.  - excerpts from the paper. For further read on this interesting article (only abstract available)  - Duraiswami, R.A., et al. (2013)

A plant whose smell mimics rotten flesh / animal excrement

It was last month, when I came across a strange smelling plant at Panchgani. I was in a midst of an open air discussion on 'Spring conservation in Western Ghats'. Suddenly I could smell something horrid, disgusting and unbearable smell in the air, something like a dog pooh or decaying animal. I could see also other participants looking at each other making disgusting faces and covering their nose. In the first place, I thought it might be some dead decaying animal around in some bush but when searched for it, to my surprise it was a small wild plant. I was really intrigued by its smell mimicking dead decaying flesh.

When asked about it to a botanist friend, I was told this "This plant is common in deciduous forests. It has a bulb in the ground. It flowers in March/ April. The photo is showing the flower. The middle stem like thing has pollen grains on the upper portion and female flowers on the lower portion enclosed by the spotted spathe (Petal like thing). The dirt loving flies are attracted by the foul smell and pollens get stuck to their legs, when they visit other flower they pollinate it. As soon as the rain comes the leaves come up though the ground. The pollinated flowers may turn into a fruit. It looks like corn cob dark green turning to sparkling red on maturity. In marathi it is called as Nurki (due to its smell). Botanical name is Typhonium venosum. Synonym is Sauromatum venosum family is Araceae. The plant is poisonous, but is planted as ornamental plant in some parts of the world"

Typhonium venosum plant (Image courtesy: wikipedia)

The fact that this plant/herb whose smell mimics dead decaying flesh or to some noses dog excrement leaves me pondering - how this plant/herb might have evolved in the wild to draw some specific insects to pollinate its species esp. the flies? So, if any of you happen to smell something horrid in the wild don't be carried away like I did.    

The horrid smelling plant in the wild. Notice the three flies sitting on the plant. (Image credit: R. Thomas)

Oldest known microscopic Zircon crystals confirms Earth's crust formation to 4.4 billion years ago

A very tiny Zircon crystals extracted from a remote rocky outcrop from Western Australia's Jack hills region has been confirmed to be formed 4.4 billion years ago - a recent study published in the journal Nature Geoscience. 

Prof. John W.Valley from University of Wisconsin-Madison spearheading a team of international scientist, have used a new technique called atom - probe tomography in conjunction with secondary ion mass spectrometer to establish accurately the age and thermal signatures of the zircon crystals by determining the mass of individual atoms of lead collected in the sample after radioactive decay of Uranium. The findings have been build on an earlier study by Prof. Valley and others, published in Nature journal that used lead isotopes to date zircon.

These tiny Zircon time capsules play an important role in radioactive dating of rocks, as they contain Uranium atoms, which sets the clock on as they start decaying into Lead. In addition they have also measured oxygen isotope ratios that sheds some light on the cooling of the Earth. This present findings will help in understanding formation of the Earth's hydrosphere and in understanding how other habitable planets form. 

Indeed we have come a long way from 4004 B.C. for the age of the Earth given by James Ussher to 4.4 billion years that comes out from this present study. 

Place of Jack hills zircon crystal (4.4 Ga) in context to the Earth's time - line.
Image credit: Andree Valley/ University of Wisconsin

Reference and Further Reading:
1. University of Wisconsin-Madison. "Oldest bit of crust firms up idea of cool early Earth." Sciencedaily. ScienceDaily, 23 February 2014.

2. John W. Valley, Aaron J. Cavosie, Takayuki Ushikubo, David A. Reinhard, Daniel F. Lawrence, David J. Larson, Peter H. Clifton, Thomas F. Kelly, Simon A. Wilde, Desmond E. Moser, Michael J. Spicuzza. (2014): Hadean age for a post-magma-ocean zircon confirmed by atom-probe tomography. Nature Geoscience.

3.Wilde, S. A., Valley, J. W., Peck, W. H. & Graham, C. M. (2001) Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago. Nature 409, 175–178.

Geo-spotlight: Observations of first ever advancing rhyolitic obsidian flow at Puyehue-Cordón Caulle volcano in Chile

A team of geologists from Lancaster University in United Kingdom, University of Mainz in Germany and Victoria University of Wellington in New Zealand have reported for the first time a slow advancing lava flow of rhyolitic (more sticky and viscous lava than the usual red hot flowing basaltic lava) obsidian down the slopes of Puyehue-Cordón Caulle volcano in Chile, in their recent research article in Nature Communications. The most fascinating observation of this flow is that after almost a year from its last eruption in April 2012, when the lava from the vent had ceased to extrude; the flow is still progressing when visited by the team in January 2013.

Puyehue-Cordón Caulle volcano and its obsidian lava flow, still going nearly a year after the volcano stopped erupting. Credit: NASA Earth Observatory.

The reason for the slow flow is attributed to the thick carapace of solidified rubble strewn slabs, which has kept the lava core insulated from losing heat to the surrounding. Dr. Hugh Tuffen, a researcher from Lancaster University adds, “The effectiveness of the insulation provided by the ~10 m-thick upper crust is staggering - these things may keep moving for years to come. Viscous heating and latent heat of crystallisation in the interior can also help to keep them warm.”

Their results demonstrate how efficient thermal insulation by the shell of solidified lava crust allows prolonged advance of compound rhyolitic flow fields, and reveals unexpected resemblance with processes at basaltic lava flow fields elsewhere. This very unique flow is under the 'Geo-spotlight' and further similar studies of active lava fields will shed lights on the strange motion and emplacement of lava flows in general.

Photo images of the flow in concert with satellite images were used in constructing a 3D animation of the thick flow front. The animation created by a team member Dr. James Mike can be viewed on the BBC news website.

Earthquake pangs and the rise of new born mud volcano off the coast of Pakistan

Earthquake relief is yet to reach certain remote places of Pakistan's Sindh and Balochistan province due to 7.7 magnitude earthquake (on the Richter scale) that struck the region leaving 500 people dead followed by saturday's massive aftershock measuring 6.8. The earthquake owes its birth to grinding of the two plates Indian and the Eurasian plates along the Chaman fault zone, triggering the destructive temblors. The official death count stands at 515, unofficial figures are as high as 700, with more than 800 injured (and counting). The earthquake has left more than 50,000 people homeless in these areas. I hope they receive the required help and attention.

But what has caught the eyes of many people is the rise of a new island off the port of Gwadar after the Fridays quake. The island is about 60 to 70 feet (18 to 21 meters) high, up to 300 feet (91 meters) wide, and up to 120 feet (37 meters) long. 

The new island that emerged from the sea following Fridays earthquake, off Pakistan's Gwadar coastline in the Arabian sea. (Source: Reuters)

The reason for the rise of the mud volcano is attributed to the seismic waves causing fluid material under the seafloor to expand under the crust giving way to pressurized fluid and gases to rise, spitting out buried mud with rocks and other seafloor creatures. Evidence of rocks and stones suggest that the mud might have been thrown out of the sea at great speed. The island will soon disappear under the sea as the waves will erode away the island rocks.

Further reading on the causes of the rise of mud volcano - LiveScience.com and also images from NASA Earth Observatory (before and after the rise of the new island).

And similar articles of rise of similar new mud volcano islands off the coast of Trinidad and Tobago in the recent century.

Biodiversity at its best: My Neighbours

Living at the edge of a forest that has taken approx. 30 yrs to regrow by itself from a barren land to a forest thriving with life and providing a unique habitat for a diverse kinds of living organisms. By the way the forest I am talking about lies just at the foothills of the famous Panchgani tableland. 

It has been one year and four months of an amazing experience living at the edge of a living forest with creatures that are so incredible and beautiful to watch. Though not a wildlife expert at documenting the rich biodiversity that this small patch of forest holds, I have made a humble attempt to note down things that I have been seeing every day since my stay at Panchgani. Experiencing the entire weather of the year out here and noticing certain organisms being found only in a particular month or season and then not to see the same insects or birds in the rest of the months is so intriguing and leaves me with big questions like - WHY & HOW? With the help field guides like Birds of the Indian Subcontinent (Richard Grimmett et al), the book of Indian animals (Prater), Snakes of India: The field Guide (Romulus Whitaker & Ashok Captain) and many online resources; like this one was really helpful - www.indiabirds.com a good tool for identification of birds.

Below is the list of diverse fauna from insects, mammals, amphibians, reptiles to birds; documented from October 2011 until the date of this post and the list is growing even though I post this exhaustive list now. I  hope this list is helpful to appreciate and accept that we are not alone and we share our surrounding with some of the most beautiful creatures that are so essential for the functioning of the ecosystem. Our approach so far in management of our environment or its resources like forest or water have always been anthropocentric forgetting we also need this creatures to complete what we call our Earth - a Home for all. This list will remind us to share our resources with creatures that too have important role in the environment just like we think 'we do'.

Avifauna: (104 Birds)

Red-whiskered Bulbul (emeria)

Red-vented Bulbul (humayuni)

Square-tailed Bulbul (Hypsipetes (leucocephalus) ganeesa)

Great Tit (Parus major)

Indian Yellow Tit (Parus (xanthogenys) aplonotus)

Brown-headed Barbet (caniceps)

Coppersmith Barbet

Jungle Bush Quail

Common Quail

Red Spurfowl

Rose-ringed Parakeet

Small Minivet (malabaricus, cinnamomeus)

Orange Minivet (Pericrocotus flammeus)

Black Drongo

White-bellied Drongo (leucopygialis?)

Indian Peafowl

Asian Paradise-flycatcher

Red-breasted Flycatcher/ Red-throated Flycatcher

White-spotted Fantail

White-browed Fantail

Indian Nightjar

Indian Scimitar Babbler (horsfieldii)

Tawny-bellied Babbler (hyperythra)

Jungle Babbler

Malabar Lark

Pied Bushchat

Oriental White-eye

Common tailor bird

Pale bellied flowerpecker

Purple-rumped Sunbird

Purple Sunbird

Vigor’s Sunbird

Loten’s Sunbird

Black-winged Kite/ Black-shouldered Kite

Black Kite

Crested Serpent Eagle

Laggar Falcon

Oriental Magpie Robin

Indian Robin (fulicatus)

Common Pigeon

Spotted Dove

Glossy Ibis (Plegadis falcinellus)

Laughing Dove

Asian Koel

Southern Coucal

Indian Scops Owl

Red Rumped Swallow

Wire-tailed Swallow

Dusky Crag Martin

Jungle Myna (fuscus)

Common Myna

Greenish Warbler

Blyth’s Reed Warbler

Indian Jungle Crow

House Crow

Grey-breasted Prinia (hodgsonii)

Indian Grey hornbill

White-throated Kingfisher

Malabar Whistling Thrush

Rufous Treepie

Green Bee-eater

Long-tailed Shrike

White-browed wagtail

Scaly-breasted Munia (Lonchura punctulata)

House Sparrow (Passer domesticus)

Common Woodshrike

Common Kestrel (Falco tinnunculus)

Indian Pond Heron (Ardeola bacchus)

Cattle Egret (Bubulus ibis)

Baya Weaver (Ploceus philippinus)

Indian Blackbird (Tardus nigropileus)

Black hooded Oriole (Oriolus xanthornus)

Crested Bunting

Red-wattled Lapwing

Green Warbler [Phylloscopus( trochiloides) nitidus]

Indian Bushlark

Yellow crowned Woodpecker

Indian Golden Oriole

Orange-headed Thrush (cyanotus)

Indian Blackbird (Tardus merula nigropileus)

Yellow Wagtail

Yellow-eyed Babbler (Chrysomma sinense)

Tytler’s Leaf Warbler

Black Eagle (Ictinaetus malayensis)

Grey Wagtail

Grey Heron (Ardea cinerea)

Ashy Drongo (Dicrurus leucophaeus)

Western Crowned Warbler (Phylloscopus occipitalis)

Ultramarine Flycatcher

Verditer Flycatcher

Black-headed Ibis (Threskiornis melanocephalus)

Tawny Eagle (Aquila rapax)

Southern Grey Shrike (Lanius meridionalis)

Greater Short-toed Lark

Shaheen Falcon

Yellow-footed Green Pigeon

Brahminy Kite (Haliastur indus)

Crested Hawk Eagle (Nisaetus cirrhatus)

Common Hawk Cuckoo (Hierococcyx varius)

White-cheeked Barbet (Megalaima viridis)

Common Iora

Brown Shrike (Lanius cristatus)

Indian Roller (Coracias benghalensis)

Oriental Skylark (Alauda gulgula)

Reptiles: 

Phipsons Shield Tail

Spotted yellow Wolf Snake

Common Krait

Indian Cobra

Travancore Wolf Snake

Rat Snake

Montane Trinket Snake

Large-scaled Sheildtail

Beddome’s Cat Snake

Mahabaleshwar Shield tail

Indian Rock Python (This one I should mention, that I saw this swallowing a Red-vented Bulbul whole. Though caught it on my mobile camera but didn't come out so clear)

Green Keelback

Elliot’s Sheildtail

Amphibians:

Skink

Geckos (Deccan Banded Gecko)

Frogs

Toads

Monitor Lizard

Garden Lizard

Mammals: 

Indian Chevrotain/ Mouse-Deer

Bonnet Macaque

Common Langur (Presbytis entellus)

Common Mongoose

Wild Pigs

Hare

Bats

Indian Porcupine (Hystrix indica)

Indian Field Mouse

Indian mole rat

Three striped Palm Squirrel (Funambulus palmarum)

Indian Pangolin (Manis crassicaudata)

Insects:

Butterflies

Moths

Ants

Termites

Glow worms

Slugs

Caterpillar

Earthworms

Honeybee

Flies
Dragon fly

Bumblebee

Centipede

Garden Spider

Wolf Spider

Cicada

Dung beetle

Rhinoceros Beetle

Shovel-headed Beetle

Diving Beetle

Cockroaches

Millipedes

Ticks

Earwig

The photos below will give you a small view into the list I am talking about. Had I had my own camera, I would have posted more photos. Well, special thanks to my workplace and others for providing me with the photos. 

I will be glad if anyone can identify this snake. Looks to me a cobra with the spectacle-mark on its back but this one was quite different then the other snakes that i have seen so far (some say it is a Rat snake). It lie dead on one of the road sides inside the campus in the night (Photo credit: Aparna Shrivastava)

The Rhinoceros Beetle

The Shovel Beetle (P.S This and the picture above belong to the same family but have different tools on their head)

The shiny insect (anyone to name it differently or give me its scientific name, please feel free)

Butterfly caterpillar (Photo Credit: Rachel Jacobson)

This hairy worm is seen only in winter from Dec to Jan (Slugs in the monsoon, this hairy worm in winter and now what I see around is a worms with black hair, quite amazing different timings for these worms to make their short lived dominion known)

Giant centipede (out hunting in the night)

Bee's nest (honeycomb) on an Eucalyptus tree

Phipson's Shieldtail (this guy didn't like that I took it on a stick)

Phipson's Shieldtail (Uropeltis phipsonii) -  the moment I left it on the ground it started digging to move down the ground 

Travancore Wolf Snake

Orange Minivet - Female (Pericrocotus flammeus). (Photo Credit: Anandi Gandhi)

Orange Minivet - Male (Pericrocotus flammeus). These birds are seen in groups of 4 to 5 in the morning and esp in the evening (Photo Credit: Anandi Gandhi)

Garden lizard giving the right pose in front of the camera

Red-breasted Flycatcher

The majestic Asian Paradise Flycatcher and my favorite bird.

Red Whiskered Bulbul

Scary spider (I must mention here that there are so many different spiders out here and  new spiders seen every week.  I would suggest someone comes out here and does a proper research on spiders -  a good place to identify new one and document them)

White-cheeked Barbet (This guy crashed on to my window,  tried to put on water to revive his strength but ended up hitting another window when it tried to fly and then finally took off).  

Skink

I call it a Showel worm (It is interesting to note out here is that worms and insects that i have noticed have interesting tools on their head to dig through the ground. If some one knows a better name please let me know)

Anyone to give name to this  interesting creature. Found laid under soil rich with moisture and other small insects (Coin is for scale)

Black Moth 1

Moth 2 (Night time is the time of the moths)

Butterfly

Deccan Banded Gecko seen on one of my night treks

Praying mantis

Cat-legged spider (two of its leg not in place)

Was almost 2 meters long with its head into the cement bags, didn't want to disturb it so was not able to see its head. But it is a Rat snake

Common Krait on the table land on one of my night treks

Toad

Black-shouldered Kite

Indian roller (Photo Credit: Aparna Shrivastava)

Green Bee-eater (Photo Credit: Rachel Jacobson)

Pretty looking Butterfly

Millipede

Two Common Langur (Presbytis entellus) staring at  me when taking their photo.

Two cricket's sitting on a tree branch, was not that easy to spot them especially their body completely blending with the colour of the branch. I was able to spot them by fine tuning my ear to their sound.

White-throated Kingfisher (Photo Credit: Rachel Jacobson)

Quite common to see them early mornings and in the evening with their melodious sound - Pied Bushchat (Photo Credit: Rachel Jacobson)

Special thanks to Dr. Girish Jathar (Orinthologist) for going through the list and correcting some of my errors.