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Site of mega-development project in Mexico is a biodiversity hotspot

A young man overlooks his home, the coastal community of Cabo Pulmo. Credit: Octavio Aburto.

Cabo Pulmo is a close-knit community in Baja California Sur, Mexico, and the best preserved coral reef in the Gulf of California. But now the lands adjacent to the reef are under threat from a mega-development project, “Cabo Dorado,” should construction go ahead.

Scientists at the University of California, Riverside have published a report on the terrestrial biodiversity of the Cabo Pulmo region that shows the project is situated in an area of extreme conservation value, the center of which is Punta Arena, an idyllic beach setting proposed to be completely cleared to make way for 20,000+ hotel rooms.

“Until recently, the biological value of the lands adjacent to the coral reef of Cabo Pulmo had remained a mystery,” said UC Riverside’s Benjamin Wilder, who helped produce the report. “We now know that these desert lands mirror the tropical waters in importance. This desert-sea ecosystem is a regional biodiversity hotspot.”

According to Wilder, if the Cabo Dorado project proceeds as planned, the regionally endemic plant species and vegetation of Punta Arena will be made extinct.

“Forty-two plants and animals on the Mexican endangered species list would lose critical habitat, two recently described plant species only known from Punta Arena would be lost entirely, and development of the sand dunes of Punta Arena would imperil the most diverse coral reef in the Gulf of California,” he said.

The report resulted from a survey conducted in November 2013 that in just a week’s time documented 560 plants and animals on the land surrounding Cabo Pulmo. The report highlights the unique and ecologically important habitats of the sand spit, Punta Arena, the core zone of the pending development proposal.

The ‘bioblitz’ and resulting report were organized by UCR alum Sula Vanderplank, a biodiversity explorer with the Botanical Research Institute of Texas, and Wilder, a Ph.D. graduate student in the Department of Botany and Plant Sciences, with their advisor Exequiel Ezcurra, a professor of ecology at UCR. The report represents a binational collaboration of 22 scientists from 11 institutions that participated in the expedition and are the top experts on the plants, birds, mammals, and reptiles of Baja California. The survey was organized using the Next Generation of Sonoran Desert Researchers network to assemble a ‘dream-team’ of field biologists.

Ezcurra, the director of UC MEXUS and an acclaimed conservationist, said, “We need to take a careful look at such large scale development projects. Far too many times along the coasts of Mexico we have seen the destruction of areas of great biological importance and subsequent abandonment. By incorporating the natural wealth of the region into development initiatives we can collectively pursue a vision of a prosperous future for our communities that matches the grandeur of the regional landscape.”

In the early 1990s the local community of Cabo Pulmo saw that overfishing was greatly depleting the coral reef ecosystem. The community shifted its local economy to ecotourism and non-extractive livelihoods, and lobbied the Mexican government to make the reef a national park, which was realized in 1995. Since that time there has been a more than 460 percent increase in the total amount of fish in the reserve — the most robust marine reserve in the world.

Wilder, Ezcurra and Vanderplank stress in the report that it is very important that development in this area take into account the inherent limitations of resources, especially fresh water, in a desert setting; the unique habitats found at Punta Arena and the coral reefs of Cabo Pulmo; and, perhaps most important, the local community of Cabo Pulmo.

“We were surprised to see that these desert lands mirrored the biological diversity of the adjacent coral sea,” Wilder said. “Specifically we were not expecting to find such a concentration of rare and endemic taxa in the single region of Punta Arena. This unique biodiversity results from regional geologic forces that were previously un-investigated.

“The bottom line is that the scale of the proposed development, more than 20,000 hotel rooms, is completely disconnected from the ecology of this desert region,” he added. “Any development in the area must account for and sustain the areas natural wealth as well as the local communities of Cabo Pulmo and the nearby town of La Ribera.”

The research team has proposals pending to better understand the linkage between the desert-sea interface of this coastal area. Their aim is to further establish the value of the biological richness of Cabo Pulmo and Punta Arena.

The final report, which based on the scientific results recommends an extension of the Cabo Pulmo National Park to include Punta Arena, was delivered at a public hearing to SEMARNAT, the Mexican federal environmental department. SEMARNAT is expected to make a decision on the future of the Cabo Dorado project by June 15, 2014.

The report is available here

Note : The above story is based on materials provided by University of California – Riverside.

Lazulite

Lazulite near Rapid Creek, Yukon, Canada Miniature, 5.4 x 5.1 x 2.4 cm © irocks “irocks.com”

Chemical Formula: (Mg,Fe2+)Al2(PO4)2(OH)2
Locality: Werfen, Salzburg, Austria
Name Origin: From the Arabic azul – “sky” and the Greek lithos – “stone.”

Lazulite ((Mg,Fe2+)Al2(PO4)2(OH)2) is a blue, phosphate mineral containing magnesium, iron, and aluminium phosphate. Lazulite forms one endmember of a solid solution series with the darker iron rich scorzalite.

Lazulite crystallizes in the monoclinic system. Crystal habits include steep bipyramidal or wedge-shaped crystals. Lazulite has a Mohs hardness of 5.5 to 6 and a specific gravity of 3.0 to 3.1. It is infusible and insoluble.

History

Discovery date : 1795

Optical properties

Optical and misc. Properties : Subtranslucent to opaque
Refractive Index : from 1,61 to 1,64
Axial angle 2V: 69°

Physical Properties

Color: Blue, Blue green, Light blue, Black blue.
Density: 3 – 3.1, Average = 3.05
Diaphaneity: Subtranslucent to opaque
Fracture: Uneven – Flat surfaces (not cleavage) fractured in an uneven pattern.
Hardness: 5-6 – Between Apatite and Orthoclase
Luminescence: Non-fluorescent.
Luster: Vitreous (Glassy)
Streak: white

Photos:

Lazulite Near Rapid Creek, Yukon, Canada Miniature, 3.9 x 3.0 x 1.9 cm © irocks ” irocks.com”
Lazulite, siderite and quartz Rapid Creek – Dawson Mining distr. – Yukon Territory – Canada Specimen weight:66 gr. Crystal size:mm. 7 Overall size: 55mm x 26 mm x 17 mm © minservice
Graves Mountain, Lincoln Co., Georgia, USA © 2001 John H. Betts

Mars mineral could be linked to microbes

The late Dr Linda Moore sampling microbialites. Credit: Bob Burne

Scientists have discovered that the earliest living organisms on Earth were capable of making a mineral that may be found on Mars.

The clay-mineral stevensite has been used since ancient times and was used by Nubian women as a beauty treatment, but scientists had believed deposits could only be formed in harsh conditions like volcanic lava and hot alkali lakes.

Researchers led by Dr Bob Burne from the ANU Research School of Earth Sciences have found living microbes create an environment that allows stevensite to form, raising new questions about the stevensite found on Mars.

“It’s much more likely that the stevensite on Mars is made geologically, from volcanic activity,” Dr Burne said.

“But our finding — that stevensite can form around biological organisms — will encourage re-interpretation of these Martian deposits and their possible links to life on that planet.”

Dr Burne and his colleagues from ANU, University of Western Australia and rock imaging company Lithicon, have found microbes can become encrusted by stevensite, which protects their delicate insides and provides the rigidity to allow them to build reef-like structures called “microbialites.”

“Microbialites are the earliest large-scale evidence of life on Earth,” Dr Burne said. “They demonstrate how microscopic organisms are able to join together to build enormous structures that sometimes rivalled the size of today’s coral reefs.”

He said the process still happens today in some isolated places like Shark Bay and Lake Clifton in Western Australia.

“Stevensite is usually assumed to require highly alkaline conditions to form, such as volcanic soda lakes. But our stevensite microbialites grow in a lake less salty than seawater and with near-neutral pH.”

One of the paper’s authors, Dr Penny King from ANU, is a science co-investigator on NASA’s Mars Curiosity rover, which uncovered the presence of possible Martian stevensite.

The findings also have implications for how some of the world’s largest oil reservoirs were formed.

The discovery was made using ANU-developed imaging technology licensed to Lithicon. The data was run on Raijin, the most powerful supercomputer in the Southern Hemisphere, based at the National Computational Infrastructure in Canberra.

Journal Reference:

R. V. Burne, L. S. Moore, A. G. Christy, U. Troitzsch, P. L. King, A. M. Carnerup, P. J. Hamilton. Stevensite in the modern thrombolites of Lake Clifton, Western Australia: A missing link in microbialite mineralization? Geology, 2014; DOI: 10.1130/G35484.1

Note : The above story is based on materials provided by Australian National University.

Fossils prove useful in analyzing million year old cyclical phenomena

Professor Francisco J. Rodríguez-Tovar, of the University of Granada, pointing to the bio-event in the late Cretaceous/early Tertiary (when the dinosaurs became extinct) in Agost (Alicante). Credit: Image courtesy of University of Granada

Analysing palaeontological data helps characterize irregular paleoenvironmental cycles, lasting between less than 1 day and more than millions of years.

Francisco J. Rodríguez-Tovar, Professor of Stratigraphy and Paleontology at the University of Granada has shown that the cyclical phenomena that affect the environment, like climate change, in the atmosphere-ocean dynamic and, even, disturbances to planetary orbits, have existed since hundreds of millions of year ago and can be studied by analysing fossils.

This is borne out by the palaeontological data analysed, which have facilitated the characterization of irregular cyclical paleoenvironmental changes, lasting between less than 1 day and up to millions of years.

Francisco J. Rodríguez-Tovar, Professor de Stratigraphy and Paleontology at the University of Granada, has analysed how fossil records can be used as a key tool to characterize these cyclical phenomena that have varying time scales.

The results of this research have been published in the prestigious journal Annual Reviews of Earth and Planetary Sciences, the second-ranked journal in the category of Geosciences, Multidisciplinary in the Journal Citation Reports ranking, after Nature Geosciences, with an impact factor close to 9. Never before has a Spanish scientist succeeded in having an article published in this journal.

As Dr Rodríguez-Tovar indicates, these are cyclical phenomena of a variable scale, from less than a day to more than millions of years, and which have appeared in different ways in the fossil record.

In the case of those lasting between less than 1 day and 1 year, “these are phenomena on an ecological scale essentially associated with variations in tidal and solar cycles that were recorded in the models of growth of organisms like bivalve shells or corals. Hence, we find evidence of them in fossils dating from the Paleozoic (more than 500 million years ago)”, says Prof. Rodríguez-Tovar of the University of Granada.

Moreover, in his article he has studied cyclical phenomena that have lasted between 1 year and 10,000 years, like those associated with the El Niño phenomenon (a cyclical climactic phenomenon causing the warming of South American seas), the so-called Dansgaard-Oeschger Cycles or the Heinrich Events. The latter took place during the last Ice Age, and determined variations in the abundance, distribution and diversity of populations and marine and terrestrial species.

Also, he has analysed cyclical phenomena of between 10 000 and 1 million years ago, essentially associated with climactic changes due to orbital variations (Milankovitch cycles), that are recorded in the evolutionary patterns of specific species, even bringing about their extinction.

Finally, Professor Rodríguez-Tovar has studied cyclical changes lasting over 1 million years, occurring throughout the Phanerozoic period, which are interpretation as being associated with extraterrestrial phenomena (meteorite impacts, such as those occurring in the late Cretaceous/early Tertiary, some 65 million years ago) or terrestrial phenomena (such as large-scale volcanism).

“These changes are related with major periodic extinctions, which affect a high percentage of the biota, since in most cases more than 65% of living organisms became extinct”, Prof. Rodríguez-Tovar points out.

Journal Reference:

Francisco J. Rodríguez-Tovar. Orbital Climate Cycles in the Fossil Record: From Semidiurnal to Million-Year Biotic Responses. Annual Review of Earth and Planetary Sciences, 2013; 42 (1): 140205180347002 DOI: 10.1146/annurev-earth-120412-145922

Note : The above story is based on materials provided by University of Granada.

Lawsonite

Lawsonite – Mendocino Co., California, USA Specimen weight:33 gr. Crystal size:Up to 9 mm Overall size: 40mm x 37 mm x 20 mm © minservice

Chemical Formula: CaAl2(Si2O7)(OH)2·H2O
Locality: Reed Station, Tiburon peninsula, Marin County, California, USA.
Name Origin: Named for Andrew Cowper Lawson (1861-1952), Scottish-American geologist.

Lawsonite is a hydrous calcium aluminium sorosilicate mineral with formula CaAl2(Si2O7)(OH)2·H2O. Lawsonite crystallizes in the orthorhombic system in prismatic, often tabular crystals. Crystal twinning is common. It forms transparent to translucent colorless, white, and bluish to pinkish grey glassy to greasy crystals. Refractive indices are nα=1.665, nβ=1.672 – 1.676, and nγ=1.684 – 1.686. It is typically almost colorless in thin section, but some lawsonite is pleochroic from colorless to pale yellow to pale blue, depending on orientation. The mineral has a Mohs hardness of 8 and a specific gravity of 3.09. It has perfect cleavage in two directions and a brittle fracture.

Lawsonite is a metamorphic mineral typical of the blueschist facies. It also occurs as a secondary mineral in altered gabbro and diorite. Associate minerals include epidote, titanite, glaucophane, garnet and quartz. It is an uncommon constituent of eclogite.

It was first described in 1895 for occurrences in the Tiburon peninsula, Marin County, California. It was named for geologist Andrew Lawson (1861–1952) of the University of California by two of Lawson’s graduate students, Charles Palache and Frederick Leslie Ransome.

History

Discovery date : 1895
Town of Origin: PENINSULE DE TIBURON, MARIN CO., CALIFORNIE
Country of Origin : USA

Optical properties

Optical and misc. Properties: Translucent to transparent
Refractive Index: from 1,66 to 1,68
Axial angle 2V : 76-87°

Physical Properties

Cleavage: {010} Perfect, {001} Perfect, {110} Poor
Color: Colorless, White, Gray, Blue, Pinkish.
Density: 3.09
Diaphaneity: Translucent to transparent
Fracture: Brittle – Uneven – Very brittle fracture producing uneven fragments.
Hardness: 7.5 – Garnet
Luminescence: Non-fluorescent.
Luster: Vitreous – Greasy
Magnetism: Nonmagnetic
Streak: white

Photos:

Lawsonite Comments: Glaucophane schist with a heavy druse of lawsonite crystals. Location: Reed Station, Tiburon, Marin County, California, USA. Scale: Crystal size 7 mm. Copyright: © John Veevaert
Lawsonite Mendocino County, California small cabinet – 8 x 5.5 x 4.0 cm © marinmineral
Lawsonite, 6 cm, from Mendocino County, California. © Marin Minerals specimen and photo.
Reed Station, Tiburon Uplands Nature Preserve, Tiburon Peninsula, Marin Co., California, USA

GeoTriple for Oil & Gas Exploration

GeoTriple for Oil&Gas Exploration is a Geoforge geoscience software-platform that handles Oil&Gas Exploration (i.e. Wells, 2D and 3D seismic surveys).

  • Storage and basic operations on Wells, 2D and 3D seismic surveys are supported.
  • Visualize objects and attributes with earth viewers and well-log viewers.
  • Handle shapefile format.
  • Select/unselect, and visualize top-level objects,
  • Analyse, interpret and process with selected objects and respective attributes
  • Handle OGC Services as GeoZilla.

Table of Contents

Screenshot :

Download:

Version:  0.6.1

Note : ©2011-2014 Geoforge project Key points

Climate change, forest fires drove widespread surface melting of Greenland ice sheet

Kaitlin Keegan, the study’s lead author and a Dartmouth doctoral student, investigates the newly deposited snow layering, known as firn, in the Greenland ice sheet. Credit: Laura Levy

A Dartmouth-led study finds that rising temperatures and ash from Northern Hemisphere forest fires combined to cause large-scale surface melting of the Greenland ice sheet in 1889 and 2012. This contradicts conventional thinking that the melting was driven by warming alone.

The findings suggest that continued climate change will result in nearly annual widespread melting of the ice sheet’s surface by the year 2100. Melting in the dry snow region does not contribute to sea level rise. Instead, the meltwater percolates into the snowpack and refreezes, leaving a less reflective surface. This reformed surface becomes even more susceptible to future melting due to the surface’s reduced reflectance. The ability to reflect sunlight is known as “albedo.”

The study, conducted by Thayer School of Engineering and the Desert Research Institute, is reported in the Proceedings of the National Academy of Sciences. The research was supported by the National Science Foundation and NASA.

“The widespread melting of the Greenland ice sheet required the combination of both of these effects — a lowered snow albedo from ash and unusually warm temperatures — to push the ice sheet over the threshold,” says Kaitlin Keegan, the study’s lead author and a Dartmouth doctoral student. “With both the frequency of forest fires and warmer temperatures predicted to increase with climate change, widespread melt events are likely to happen much more frequently in the future.”

The massive Greenland ice sheet experiences annual melting at low elevations near the coastline, but surface melt is rare in the dry snow region in its center. In July 2012, however, more than 97 percent of the ice sheet experienced surface melt, the first widespread melt during the era of satellite observation. Keegan, who added critical information to NASA’s announcement of the 2012 melt, studies the newly deposited layers of snow that top the 2-mile-thick ice sheet.

In the new study, an analysis of six Greenland shallow ice cores from the dry snow region confirmed that the most recent prior widespread melt occurred in 1889. An ice core from the center of the ice sheet demonstrated that exceptionally warm temperatures combined with black carbon sediments from Northern Hemisphere forest fires reduced albedo below a critical threshold in the dry snow region and caused the large-scale melting events in both 1889 and 2012.

The study did not focus on analyzing the ash to determine the source of the fires, but the presence of a high concentration of ammonium concurrent with the black carbon indicates the ash’s source was large boreal forest fires during the summer in Siberia and North America in June and July 2012. Air masses from these two areas arrived at the Greenland ice sheet’s summit just before the widespread melt event. As for 1889, there are historical records of testimony to Congress of large-scale forest fires in the Pacific Northwest of the United States that summer, but it would be difficult to pinpoint which forest fires deposited ash onto the ice sheet that summer.

The researchers also used Intergovernmental Panel on Climate Change data to project the frequency of widespread surface melting into the year 2100. Since Arctic temperatures and the frequency of forest fires are both expected to rise with climate change, the researchers’ results suggest that large-scale melt events on the Greenland ice sheet may begin to occur almost annually by the end of century. These events are likely to alter the surface mass balance of the ice sheet, leaving the surface susceptible to further melting. The Greenland ice sheet is the second largest ice body in the world after the Antarctic ice sheet.

“Our Earth is a system of systems,” says Thayer Professor Mary Albert, co-author of the study and the director of the U.S. Ice Drilling Program Office. “Improved understanding of the complexity of the linkages and feedbacks, as in this paper, is one challenge facing the next generation of engineers and scientists — people like Kaitlin.”

Note : The above story is based on materials provided by  Dartmouth College.

Laurionite

Laurionite Comments: Colorless, stellate spray of acicular Laurionite crystals on matrix. Location: Laurium, Greece. Copyright: © Lou Perloff / Photo Atlas of Minerals

Chemical Formula: PbCl(OH)
Locality: Ancient lead slags at Laurium, Greece.
Name Origin: Named after its locality.

Laurionite (PbCl(OH)) is a lead halide mineral. It forms colorless to white crystals in the orthorhombic crystal system and is dimorphous with paralaurionite, both members of the matlockite group.

It was first described in 1887 for an occurrence in the Laurium District, Attica, Greece and named after the town Laurium. It occurs as an oxidation product in lead ore deposits, and is also produced on lead-bearing slag by reaction with saline solutions. It occurs associated with paralaurionite, penfieldite, fiedlerite, phosgenite, cerussite and anglesite.

History

Discovery date : 1887
Town of Origin : LAURION, ATTIQUE
Country of Origin : GRECE

Optical properties

Optical and misc. Properties : Transparent.
Refractive Index: from 2,07 to 2,15
Axial angle 2V: LARGE

Physical Properties

Cleavage: {010} Distinct
Color: Colorless, White.
Density: 6.24
Diaphaneity: Transparent.
Hardness: 2.5-3 – Finger Nail-Calcite
Luster: Adamantine – Pearly
Streak: white

Photos:

Laurionite Juliushutte, Harz Mountains, Germany Size: 2 x 2 x 1.5 cm – Thumbnail  ©  Dakota Matrix Minerals, Inc.
Origin: Laurium, Greece Owner: Lou Perloff Microscopic image
Thorikos Bay slag locality, Thorikos area, Lavrion District slag localities, Lavrion District (Laurion; Laurium), Attikí Prefecture (Attica; Attika), Greece © Elmar Lackner

The next ‘Big One’ for the Bay Area may be a cluster of major quakes

Aerial photo of the San Andreas Fault in the Carrizo Plain, northwest of Los Angeles. Credit: Wikipedia.

A cluster of closely timed earthquakes over 100 years in the 17th and 18th centuries released as much accumulated stress on San Francisco Bay Area’s major faults as the Great 1906 San Francisco earthquake, suggesting two possible scenarios for the next “Big One” for the region, according to new research published by the Bulletin of the Seismological Society of America (BSSA).

“The plates are moving,” said David Schwartz, a geologist with the U.S. Geological Survey and co-author of the study. “The stress is re-accumulating, and all of these faults have to catch up. How are they going to catch up?”

The San Francisco Bay Region (SFBR) is considered within the boundary between the Pacific and North American plates. Energy released during its earthquake cycle occurs along the region’s principal faults: the San Andreas, San Gregorio, Calaveras, Hayward-Rodgers Creek, Greenville, and Concord-Green Valley faults.

“The 1906 quake happened when there were fewer people, and the area was much less developed,” said Schwartz. “The earthquake had the beneficial effect of releasing the plate boundary stress and relaxing the crust, ushering in a period of low level earthquake activity.”

The earthquake cycle reflects the accumulation of stress, its release as slip on a fault or a set of faults, and its re-accumulation and re-release. The San Francisco Bay Area has not experienced a full earthquake cycle since its been occupied by people who have reported earthquake activity, either through written records or instrumentation. Founded in 1776, the Mission Dolores and the Presidio in San Francisco kept records of felt earthquakes and earthquake damage, marking the starting point for the historic earthquake record for the region.

“We are looking back at the past to get a more reasonable view of what’s going to happen decades down the road,” said Schwartz. “The only way to get a long history is to do these paleoseismic studies, which can help construct the rupture histories of the faults and the region. We are trying to see what went on and understand the uncertainties for the Bay Area.”

Schwartz and colleagues excavated trenches across faults, observing past surface ruptures from the most recent earthquakes on the major faults in the area. Radiocarbon dating of detrital charcoal and the presence of non-native pollen established the dates of paleoearthquakes, expanding the span of information of large events back to 1600.

The trenching studies suggest that between 1690 and the founding of the Mission Dolores and Presidio in 1776, a cluster of earthquakes ranging from magnitude 6.6 to 7.8 occurred on the Hayward fault (north and south segments), San Andreas fault (North Coast and San Juan Bautista segments), northern Calaveras fault, Rodgers Creek fault, and San Gregorio fault. There are no paleoearthquake data for the Greenville fault or northern extension of the Concord-Green Valley fault during this time interval.

“What the cluster of earthquakes did in our calculations was to release an amount of energy somewhat comparable to the amount released in the crust by the 1906 quake,” said Schwartz.

As stress on the region accumulates, the authors see at least two modes of energy release – one is a great earthquake and other is a cluster of large earthquakes. The probability for how the system will rupture is spread out over all faults in the region, making a cluster of large earthquakes more likely than a single great earthquake.

“Everybody is still thinking about a repeat of the 1906 quake,” said Schwartz. “It’s one thing to have a 1906-like earthquake where seismic activity is shut off, and we slide through the next 110 years in relative quiet. But what happens if every five years we get a magnitude 6.8 or 7.2? That’s not outside the realm of possibility.”

More information: The paper, “The Earthquake Cycle in the San Francisco Bay Region: AD 1600-2012,” will be published online May 20, 2014 by BSSA and will appear in the June print issue: DOI: 10.1785/0120120322

Note : The above story is based on materials provided by Seismological Society of America

Pumice models could help protect shipping

Scientists have used a computer model of ocean circulation to predict the movement of the rafts of floating pumice given off by an erupting underwater volcano.

These rafts can cause problems for ships, so the researchers hope their work will lead to the development of early-warning systems to let mariners avoid risky areas in the wake of an eruption.

The researchers used NEMO, the UK’s high-resolution model of ocean circulation, to represent the ocean currents around Havre, a volcano deep under the southwest Pacific that erupted in July 2012. They then used its output to calculate the movements of thousands of particles representing areas of drifting pumice.

Finally, they compared the results with what satellite images and sailors’ sightings tell us actually happened. The match was encouragingly close, showing that although it needs more development the technique is capable of accurately predicting the movement of these floating islands.

‘The eruption was far from coastal interference, so it produced a single raft spanning over 400km2 in one day, initiating a gigantic, high-precision natural experiment in surface dispersion,’ says Dr Bob Marsh of the University of Southampton.

He was part of a team led by Dr Martin Jutzeler of the National Oceanography Centre, which recently published their findings in Nature Communications. ‘It’s only recently that we’ve had oceanographic models that represent how things spread out in the ocean accurately enough to do this kind of thing, so it’s a big opportunity for new research,’ Marsh adds.

His methods can be used to predict the movement of any floating objects that are carried about the ocean by currents – he’s already applied them to everything from debris associated with accidents to icebergs and baby turtles. Although NEMO itself needs to run on national supercomputers, the additional calculations he performs based on its output can be done in mere hours on normal computing hardware, allowing scientists to respond quickly to natural disasters.

‘If we see a big undersea volcanic eruption, we can react within 24-48 hours to produce maps of where pumice will drift to over time,’ he says. ‘All we need to know is where the volcano is.’

Pumice rafts are mostly made up of tiny pieces of floating rock, less than a centimetre across, so in most cases they aren’t likely to breach a ship’s hull. They can endanger its ability to keep moving, though, for example by clogging up water intakes so that engines have no cooling and overheat. ‘It’s not like an iceberg that can sink the ship, but it could effectively cordon off a large area of ocean for several weeks, which could cost the maritime industry a lot of money,’ Marsh says.

He now hopes to work with the shipping and marine insurance industries, as well as with colleagues in the Met Office, to investigate whether these techniques can be turned into a useful information service for sailors – perhaps an add-on to the Met Office’s existing services. He is already working on developing an early-warning system for icebergs, and says it would be relatively easy to incorporate pumice raft forecasting.

More information: “On the fate of pumice rafts formed during the 2012 Havre submarine eruption.” Martin Jutzeler, Robert Marsh, Rebecca J. Carey, James D. L. White, Peter J. Talling & Leif Karlstrom. Nature Communications 5, Article number: 3660. DOI: 10.1038/ncomms4660

Note : The above story is based on materials provided by PlanetEarth Online

Laumontite

Laumontite Himalaya Mine, Mesa Grande, San Diego Co., California, USA Miniature, 4 x 3.2 x 2.5 cm “Courtesy of Rob Lavinsky, The Arkenstone, www.iRocks.com”

Chemical Formula: CaAl2Si4O12·4H2O
Locality: Nagy-Ag, Transylvania of Romania.
Name Origin: Named after the Frenchman, F. P. N. de Laumont (1747-1834).

Laumontite is a mineral, one of the zeolite group. Its molecular formula is CaAl2Si4O12·4H2O, a hydrated calcium-aluminium silicate. Potassium or sodium may substitute for the calcium but only in very small amounts.

The identification of laumontite goes back to the early days of mineralogy. It was first named lomonite by R. Jameson (System of Mineralogy) in 1805, and laumonite by René Just Haüy in 1809. The current name was given by K.C. von Leonhard (Handbuch der Oryktognosie) in 1821. It is named after Gillet de Laumont who collected samples from lead mines in Huelgoat, Brittany, making them the type locality.

Laumontite easily dehydrates when stored in a low humidity environment. When freshly collected, if it has not already been exposed to the environment, it can be translucent or transparent. Over a period of hours to days the loss of water turns it opaque white. In the past, this variety has been called leonhardite, though this is not a valid mineral species. The dehydrated laumontite is very friable, often falling into a powder at the slightest touch.

History

Discovery date : 1805
Town of Origin : MINES HUELGOET, BRETAGNE
Country of Origin : FRANCE

Optical properties

Optical and misc. Properties : Transparent to translucent to opaque
Refractive Index: from 1,50 to 1,52
Axial angle 2V : 26-47°

Physical Properties

Cleavage: {010} Perfect, {110} Perfect
Color:   Brownish, Gray, Yellowish, Pearl white, Pink.
Density: 2.25 – 2.35, Average = 2.29
Diaphaneity: Transparent to translucent to opaque
Fracture: Brittle – Conchoidal – Very brittle fracture producing small, conchoidal fragments.
Hardness: 3.5-4 – Copper Penny-Fluorite
Luminescence: Fluorescent, Short UV=Weak white, Long UV=weak white.
Luster: Vitreous (Glassy)
Streak: white

Photos :

Calcite with Laumontite Basalt Quarry, Ambariomiambana, Sambava District, Sava Region, Antsiranana Province, Madagascar Size: 17.0 x 14.0 x 8.5 cm (large cabinet) © danweinrich
Laumontite pseudomorph of phrenite, Poona Quarries, Poona, Maharashtra, India Specimen weight:512 gr. Crystal size:50 mm Overall size: 190mm x 150 mm x 70 mm © minservice
Stilbite on Laumontite Locality: Nasik, India Specimen Size: 7.3 x 4.5 x 3.0 cm (small cabinet) Largest Crystal: 3.9 cm © minclassics
La Cabrera, Madrid, Spain © David Soler

Argun River

© Kmusser

Ergune or Argun is the river which is a part of the Russia–China border. Its upper reaches are known as Hailar River (Chinese: 海拉尔河; pinyin: Hăilā’ěr Hé) in China. Its length is 1,007 mi (1,620 km). The Ergune marks the border (established by the Treaty of Nerchinsk in 1689) between Russia and China for about 944 km, until it meets the Amur River. The name derives from Buryat Urgengol ‘wide river’ (urgen ‘wide’ + gol ‘river’).
The river flows from the Western slope of the Greater Khingan Range in Inner Mongolia. Its confluence with Shilka River at Ust-Strelka forms the Amur River.

Kherlen–Ergune–Amur

In years with high precipitation, the normally exitless Hulun Lake may overflow at its northern shore, and the water will meet the Ergune after about 30 km. The Kherlen–Ergune–Amur system has a total length of 5,052 km.

Ergune in The Secret History of the Mongols

In The Secret History of the Mongols speaks legend related to the Ergüne hun Mongol ancestry. In this legend, the Mongols prevailed over other tribes and carried such slaughter among them, that in living remained no more than two men and two women. These two families, in fear of the enemy, fled to the inhospitable terrain, which included only mountains and forests and to which there was no road. Among those mountains was the abundant grass and healthy climate of the steppe. Then, legend tells that in Ergune-Khun, Mongols multiplied and become masters of iron smelting and blacksmithing. According to legend, it is the art of melting iron that has helped them escape from the mountain gorges on scope of the current Mongolian steppes, to the Kherlen River and Onon River.

Note : The above story is based on materials provided by Wikipedia

Australian tsunami database reveals threat to continent

Australia’s coastline has been struck by up to 145 possible tsunamis since prehistoric times, causing deaths previously unreported in the scientific literature, a UNSW study has revealed.

The largest recorded inundation event in Australia was caused by an earthquake off Java in Indonesia on 17 July 2006, which led to a tsunami that reached up to 7.9 metres above sea level on land at Steep Point in Western Australia.
The continent was also the site of the oldest known tsunami in the world — an asteroid impact that occurred 3.47 billion years ago in what is now the Pilbara district of Western Australia.

Details of the 145 modern day and prehistoric events are outlined in a revised Australian tsunami database, which has been extensively updated by UNSW researchers, Professor James Goff and Dr Catherine Chagué-Goff.

“Our research has led to an almost three-fold increase in the number of events identified — up from 55 in 2007. NSW has the highest number of tsunamis in the database, with 57, followed by Tasmania with 40, Queensland with 26 and Western Australia with 23,” says Professor Goff, of the UNSW School of Biological, Earth and Environmental Sciences.

“Historical documents indicate that up to 11 possible tsunami-related deaths have occurred in Australia since 1883. This is remarkable, because our tsunami-prone neighbour, New Zealand, has only one recorded death.”

Professor Goff and Dr Chagué-Goff, who also works at the Australian Nuclear Science and Technology Organisation, scoured scientific papers, newspaper reports, historical records and other tsunami databases to update the 2007 Australian database.

“And it is still incomplete. Much more work needs to be done, especially to identify prehistoric events and those on the east coast. Our goal is to better understand the tsunami hazard to Australia and the region. The geographical spread of events and deaths suggests the east coast faces the most significant risk,” says Professor Goff.

The results are published in the journal Progress in Physical Geography.

The country’s largest tsunami had been listed in 2007 as one that hit Western Australia following an earthquake off Sumba Island in Indonesia on 19 August 1977, but this rating was based on wrong information about its wave height.

Giant wave heights of about 13 metres — bigger than those of the current record-holding event in 2006 — have also been attributed to a possible tsunami on 8 April 1911 in Warrnambool in Victoria, but no hard evidence is available as yet to back this up.

The study identified three prehistoric events that had an impact across the whole of the South West Pacific Ocean: an asteroid impact 2.5 million years ago and large earthquakes about 2900 years ago and in the mid-15th Century.

Note : The above story is based on materials provided by University of New South Wales.

Langbanite

Långbanite Locality: Langban, Filipstad, Varmland, Sweden Source: William W Pinch Owner: RRUFF

Chemical Formula: (Mn2+,Ca)4(Mn3+,Fe3+)9Sb5+(SiO4)2O16
Locality: At Langbanshyttan, Vermland, Sweden and the Sjo mines near Orebro in Orebro.
Name Origin: After its locality.

History

Discovery date : 1877
Town of Origin : MINE LANGBAN, FILIPSTAD, VARMLAND
Country of Origin : SUEDE

Optical properties

Optical and misc. Properties : Opaque
Refractive Index: from 2,31 to 2,36

Physical Properties

Cleavage: {0001} Good
Color: Iron black.
Density: 4.91
Diaphaneity: Opaque
Hardness: 6.5 – Pyrite
Luster: Metallic
Streak: grayish black

Photos :

Origin: Manggruvan near Långban, Värmland, Sweden Sample size: 3.5 x 4 cm Photo courtesy of: Diederik Visser
Langbanite Comments:  Stout black langbanite crystal in white matrix. Location:  Langban, Varmland, Sweden. Copyright: © Jeff Weissman / Photographic Guide to Mineral Species
Långbanite Locality: Langban, Filipstad, Varmland, Sweden Source: William W Pinch Owner: RRUFF
Origin: Långban mine, Bergslagen ore distr., Filipstad, Värmland, Sweden (type locality) Sample size: 3 x 1.5 x 1.5 cm (top), 3.8 x 2.3 x 2.5 cm (2nd row), 3 x 2 x 2 cm (bottom) Photo courtesy of: Tom Loomis
Långban, Filipstad, Värmland, Sweden © Christopher O’Neill

Fossil palm beetles ‘hind-cast’ 50-million-year-old winters

Fifty-million-year-old fossil beetles that fed only on palm seeds are giving biologists new information about ancient climates. Credit: Image courtesy of Simon Fraser University

Fifty-million-year-old fossil beetles that fed only on palm seeds are giving Simon Fraser University biologists Bruce Archibald and Rolf Mathewes new information about ancient climates.
According to their research, published online this week in The Proceedings of the National Academy of Sciences, these fossil beetles indicate that during a period of global warming in the geological past, there were mild, frost-free winters extended even in the uplands of ancient western North America.

Working with co-authors Geoffrey Morse of the University of San Diego, California, and David Greenwood of Manitoba’s Brandon University, researchers used fossil beetles to determine winter temperatures where they couldn’t place a thermometer — in the 50-million-year-old uplands of British Columbia and Washington.

The key to their study was finding a particular group of beetles that only feed on palms.

“The natural distribution of palms is limited today to regions without significant frost days, which their seeds and seedlings can’t survive,” Archibald explains. “A cooler upland with palms indicates a specific climate type, where a temperate average yearly temperature — rather like Vancouver today — had warmer winters where palms can complete their lifecycles.”

But since detecting palm fossils is difficult, the research duo developed a new technique — they used the beetle fossils to test for the palms’ presence.

Understanding more about these temperate, yet mild winter climates by looking to the deep past may help show how natural communities are impacted by climate change, says Archibald. “We see this happening today in significant ways — warm the winters a little, and you get big changes, such as the explosion of mountain pine beetle populations that strongly affect forests and the people and economies that depend on them.

“Using the fossil record to understand climates of the deep past that had significant similarities to climates that we are now encountering may help forearm us with knowledge that will be important to our future as we increasingly experience the effects of global warming.”

The team’s research was made possible by funding from the Natural Sciences and Engineering Research Council of Canada.

Note : The above story is based on materials provided by Simon Fraser University.

Over 100 new species discovered by team in drive to document biodiversity

Vertebrate paleontologist Richard Hulbert Jr. displays the holotype fossil specimen of a lower jaw of a 5-million-year-old saber-toothed cat, Rhizosmilodon fiteae, one of 103 new species Florida Museum researchers described in 2013. Florida Museum of Natural History photo by Jeff Gage

A 5-million-year-old saber-toothed cat, the world’s oldest grape and a bizarre hermit crab were among more than 100 new species discovered by University of Florida scientists last year.
Driven in part by the urgency to document new species as natural habitats and fossil sites decline due to human influences, researchers from the Florida Museum of Natural History, located on the UF campus, described 16 new genera and 103 new species of plants and animals in 2013, with some research divisions anticipating higher numbers for 2014.

An online search shows the only other major research institution reporting similar information is the California Academy of the Sciences, which described 91 new species in 2013 and has averaged 115 per year since 2009.

“Traditionally this isn’t a number many research institutions have tracked,” said Florida Museum Director Douglas Jones. “But the extra emphasis on biodiversity due to degradation of natural habitats and accelerating extinction rate of plants and animals worldwide has placed a higher emphasis on researchers documenting and describing new species before they disappear.”

UF researchers discovered species from more than 25 countries on four continents, including 35 fossil crustaceans, 24 Lepidoptera, 17 plants (11 fossils), eight mollusks, two fossil mammals and one fossil bird, among others. Thirty-one additional species were identified in the museum’s collections by visiting researchers.

Don Davis, curator of Lepidoptera at the Smithsonian Institution’s National Museum of Natural History, said the Florida Museum has actively pursued the goals of all natural history museums, including discovering new organisms to better understand the current distributions and history of all life.

“The scientists there are providing not only new knowledge for a broad range of organisms, but also an excellent, well-documented specimen database for all future researchers in natural history,” Davis said.

Scientists often happen upon new species while working in museum collections or exploring in the field, but recent museum biodiversity projects and collaborations have focused on discovering as many new species as possible.

Museum scientists utilized advanced taxonomic methods during recent biodiversity survey projects, including DNA bar coding, a process that uses a genetic marker to identify if an organism belongs to a particular species. Some of the new species discovered during these surveys prove rare discoveries still occur.

For example, during an international effort to document all animals and plants living on and in the waters surrounding the island of Moorea in French Polynesia, Florida Museum invertebrate zoology curator Gustav Paulay dredged from the deep sea a new hermit crab that exemplifies a rarely documented process in which hermit crabs move out of their shells and harden their bodies to resemble true crabs. Patagurus rex has a broad, armored body with pointy spines and long legs connected to large claws — making it one of the most distinctive hermit crabs discovered in decades, Paulay said.

“There is this idea that we can grab a field guide and work out there as scientists,” Paulay said. “But for large chunks of the world, those resources don’t exist and the science that would support those resources is just not there.”

This is especially true for museum scientists studying some of Earth’s smallest species in remote jungles of the Congo and isolated areas of Hawaii.

Florida Museum assistant curator of Lepidoptera Akito Kawahara said new species of insects sometimes lead to powerful discoveries that affect other fields, including agriculture and medicine.

“Future research will include the investigation of a potential new species of moth in Hawaii that appears to delay plant aging by altering the process of plant senescence (aging) in leaves,” he said. “This moth could have potential for improving agriculture and extending the shelf life of some foods.”

Last year, many scientists looked for new species from the past. Museum scientists described 56 new species of fossil plants and animals. Among these, the world’s oldest-known grape species, Indovitis chitaleyae, discovered in 2005 and described in 2013, pushed the record of the Vitaceae (grape) family into the Late Cretaceous, about 66 million years ago.

Florida Museum vertebrate paleontology collections manager Richard Hulbert described the 5-million-year-old fossils of Rhizosmilidon, a carnivorous saber-toothed cat from the same lineage as the famous Smilodon fatalis from the La Brea Tar Pits of Los Angeles.

“Today’s species represent only about 1 percent of life that ever existed,” said Bruce MacFadden, Florida Museum curator of vertebrate paleontology. “It is important to understand the other 99 percent of biodiversity that once inhabited the planet, because knowledge of the kinds of plants and animals that lived here in the past provide us with a framework for understanding today’s ecosystems.”

Note : The above story is based on materials provided by University of Florida.

Lanarkite

Lanarkite Susanna Mine, Leadhills, Lanarkshire, Scotland miniature, 3.3 x 3.2 x 2.2 cm © irocks

Chemical Formula: Pb2(SO4)O
Locality: Susanna Mine, Leadhills, Lanarkshire, Scotland.
Name Origin: Named for the locality
Lanarkite is a mineral, a form of lead sulfate with formula Pb2(SO4)O. It was originally found at Leadhills in the Scottish county of Lanarkshire, hence the name. It forms white or light green, acicular monoclinic prismatic crystals, usually microscopic in size. It is an oxidation product of galena.

History

Discovery date : 1832
Town of Origin : MINE SUSANNA, LEADHILLS, LANARKSHIRE
Country of Origin : ECOSSE

Optical properties

Optical and misc. Properties : Transparent to Translucent
Refractive Index: from 1,92 to 2,03
Axial angle 2V : ~60°

Physical Properties

Cleavage: {201} Perfect, {401} Indistinct, {201} Indistinct
Color: Greenish white, Gray, Gray white, Yellow, Light yellow.
Density: 6.92
Diaphaneity: Transparent to Translucent
Fracture: Flexible – Flexible fragments.
Hardness: 2-2.5 – Gypsum-Finger Nail
Luminescence: Fluorescent, Long UV=yellow.
Luster: Adamantine – Resinous
Streak: white

Photos:

Lanarkite Location: Meadowfoot smelter, Wanlockhead, Lanarkshire, Scotland. Scale:     Not Given. Copyright: © Lou Perloff / Photo Atlas of Minerals
A divergent spray of bladed lanarkite crystals from Frongoch Mine. Individual crystals to 2.5 mm in length. Steve Rust specimen and photo. © Steve Rust.
Lanarkite: Location: Leadhills, Scotland. Scale:     Picture size 2 cm. Copyright: © Dave Barthelmy
Frongoch Mine (Bron-y-Goch Mine; Llawynwnwch Mine), Pontrhydygroes, Upper Llanfihangell-y-Creuddyn, Ceredigion (Dyfed; Cardiganshire), Wales, UK © Steve Rust

Largest dinosaur? Paleontologists unearth new heavyweight in Argentina

The new kind of dinosaur dwarfs even the Argentinosaurus, the previous largest contender. Photograph: Guardian

Paleontologists in Patagonia, southern Argentina on Friday announced they have unearthed a 90-million-year-old fossil of what they claim is the largest dinosaur found to date.

“It’s the largest example ever found,” said Ruben Cuneo, director of the Feruglio Museum of Trelew, a city founded by Welsh settlers in the 1860s.

The new kind of dinosaur dwarfs even the Argentinosaurus, the previous largest contender. It is a 40-metre (130-foot) long sauropod discovered in farmland about 260km (160 miles) from the town of Trelew.

The dinosaur weighed about 80 tons, the equivalent of 14 grown elephants, said the museum director. A complete skeleton was found in a field discovered by a farm worker last year, where up to seven such complete skeletons are believed to exist, in the locality of El Sombrero.

“It’s like two trucks with a trailer each, one in front of the other, and the weight of 14 elephants together,” said José Luis Carballido, the Argentinian paleontologist who led the dig. “This is a real paleontological treasure. There are plenty of remains and many were nearly intact, which is unusual.”

Note : The above story is based on materials provided by Uki Goni in Buenos Aires for theguardian

On the shoulder of a giant: Precursor volcano to the island of O’ahu discovered

Map showing schematically the distribution of the three volcanoes now thought to have made up the region of O’ahu, Hawai’i. From oldest to youngest these are the Ka’ena, Wai’anae, and Ko’olau Volcanoes. Upper panel: bold dashed lines delineate possible rift zones of the three volcanoes; also shown are the major landslide deposits around O’ahu. The lower panel shows how the three volcanic edifices overlap. Credit: J. Sinton, et al., UH SOEST

Researchers from the University of Hawai’i — Mānoa (UHM), Laboratoire des Sciences du Climat et de L’Environment (France), and Monterey Bay Aquarium Research Institute recently discovered that O’ahu actually consists of three major Hawaiian shield volcanoes, not two, as previously thought. The island of O’ahu, as we know it today, is the remnants of two volcanoes, Wai’anae and Ko’olau. But extending almost 100 km WNW from Ka’ena Point, the western tip of the island of O’ahu, is a large region of shallow bathymetry, called the submarine Ka’ena Ridge. It is that region that has now been recognized to represent a precursor volcano to the island of O’ahu, and on whose flanks the Wai’anae and Ko’olau Volcanoes later formed.

Prior to the recognition of Ka’ena Volcano, Wai’anae Volcano was assumed to have been exceptionally large and to have formed an unusually large distance from its next oldest neighbor — Kaua’i. “Both of these assumptions can now be revised: Wai’anae is not as large as previously thought and Ka’ena Volcano formed in the region between Kauai and Wai’anae,” noted John Sinton, lead author of the study and Emeritus Professor of Geology and Geophysics at the UHM School of Ocean and Earth Science and Technology (SOEST).

In 2010 scientists documented enigmatic chemistry of some unusual lavas of Wai’anae. “We previously knew that they formed by partial melting of the crust beneath Wai’anae, but we didn’t understand why they have the isotopic composition that they do,” said Sinton” Now, we realize that the deep crust that melted under Waianae is actually part of the earlier Ka’ena Volcano.”

This new understanding has been a long time in the making. Among the most important developments was the acquisition of high-quality bathymetric data of the seafloor in the region. This mapping was greatly accelerated after UH acquired the Research Vessel Kilo Moana, equipped with a high-resolution mapping system. The new data showed that Ka’ena Ridge had an unusual morphology, unlike that of submarine rift zone extensions of on-land volcanoes. Researchers then began collecting samples from Ka’ena and Wai’alu submarine Ridges. The geochemical and age data, along with geological observations and geophysical data confirmed that Ka’ena was not part of Waianae, but rather was an earlier volcanic edifice; Wai’anae must have been built on the flanks of Ka’ena.

“What is particularly interesting is that Ka’ena appears to have had an unusually prolonged history as a submarine volcano, only breaching the ocean surface very late in its history,” said Sinton. Much of our knowledge of Hawaiian volcanoes is based on those that rise high above sea level, and almost all of those formed on the flanks of earlier ones. Ka’ena represents a chance to study a Hawaiian volcano that formed in isolation on the deep ocean floor.

Despite four different cruises and nearly 100 rock samples from Ka’ena, researchers say they have only begun to observe and sample this massive volcanic edifice. While this article was in press, SOEST scientists visited Ka’ena Ridge again — this time with the UH’s newest remotely operated vehicle, ROV Lu’ukai — and collected new rock samples from some of its shallowest peaks. With these new samples Sinton and colleagues hope to constrain the timing of the most recent volcanism on Ka’ena.

Note : The above story is based on materials provided by University of Hawaii ‑ SOEST.

Labradorite

Labradorite Sunstone Locality: Oregon © minclassics
Chemical Formula: (Ca,Na)[Al(Al,Si)Si2O8]
Locality: Labrador peninsula, Canada.
Name Origin: Named after its locality.Labradorite ((Ca,Na)[Al(Al,Si)Si2O8]), a feldspar mineral, is an intermediate to calcic member of the plagioclase series. It is usually defined as having “%An” (anorthite) between 50 and 70. The specific gravity ranges from 2.68 to 2.72. The streak is white, like most silicates. The refractive index ranges from 1.559 to 1.573. Twinning is common. As with all plagioclase members, the crystal system is triclinic, and three directions of cleavage are present, two of which form nearly right angle prisms. It occurs as clear, white to gray, blocky to lath shaped grains in common mafic igneous rocks such as basalt and gabbro, as well as in anorthosites.

Occurrence

The geological type area for labradorite is Paul’s Island near the town of Nain in Labrador, Canada. It has also been reported in Norway and various other locations worldwide.

Labradorite occurs in mafic igneous rocks and is the feldspar variety most common in basalt and gabbro. The uncommon anorthosite bodies are composed almost entirely of labradorite. It also is found in metamorphic amphibolites and as a detrital component of some sediments. Common mineral associates in igneous rocks include olivine, pyroxenes, amphiboles and magnetite.

History

Discovery date: 1780
Town of Origin : ILE DE PAUL, LABRADOR, NEWFOUNDLAND
Country of Origin : CANADA

Optical properties

Optical and misc. Properties : Translucent to transparent
Refractive Index: from 1,55 to 1,57
Axial angle 2V: 78-87°

Physical Properties

Cleavage: {001} Perfect, {010} Good, {110} Distinct
Color: Colorless, Gray, Gray white, White, Light green.
Density: 2.68 – 2.71, Average = 2.69
Diaphaneity: Translucent to transparent
Fracture: Uneven – Flat surfaces (not cleavage) fractured in an uneven pattern.
Hardness: 7 – Quartz
Luminescence: Non-fluorescent.
Luster: Vitreous (Glassy)
Streak: white

Photos :

Labradorite Mexico Thumbnail, 21.2 x 16.5 mm ; 19.90 carats © irocks
Anorthite (Var: Labradorite) Locality: Nain Complex, Labrador, Newfoundland and Labrador, Canada Dimensions: 9 cm x 4.5 cm x 1.5 cm Photo Copyright © 2000-2003 by John H. Betts
Photo Copyright © R.Weller/Cochise College.
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