Sentences with phrase «opaline silica»

Diatoms are microscopic algae that have cell wall made of opaline silica.

Moser is an expert in diatoms, which are microscopic algae that have cell wall made of opaline silica.

«Opaline silica is basically like glass,» explains Moser, a geography professor at Western's Faculty of Social Science.

Now, a team using an imaging spectrometer aboard NASA's Mars Reconnaissance Orbiter reports the discovery of numerous patches of opaline silica across the Red Planet.

New images from the Mars Reconnaissance Orbiter show water - associated opaline silica (dark areas) scattered across the planet's surface.

Opaline silica deposits also stem from interactions with water, but they occur in places on the martian surface that formed as recently as 2 billion years ago, the researchers report in the November issue of Geology.

The three lines are: (1) the beginning: the Khirthar transgression and the onset of neritic carbonate accumulation in the Bartonian Age (preceding onset of the Middle Eocene climatic optimum [MECO]-RRB-; (2) the midlife change (Bartonian - Priabonian transition): the shift from carbonate - rich to carbonate - poor, higher - nutrient environments under estuarine circulation, causing widespread dysaerobia culminating in opaline silicas; and (3) the Eocene - Oligocene = Priabonian - Rupelian boundary and glaciation during oxygen isotope event Oi - 1, with return of improved ventilation in neritic environments and resumption of carbonate accumulation.