Results 71 to 80 of about 5,797 (153)

Spherulite in the modern aragonitic travertine stromatolite has a calcite core with exopolymers

Sedimentology, EarlyView.
ABSTRACT Spherulites are spherical to ellipsoidal particles formed by various crystalline substances and can be abiotically synthesised in the laboratory. Among various spherulite types, spherulites composed of calcium carbonate are also found in various natural environments, but their abiotic or biotic origins are still controversial.
Fumito Shiraishi, Takayuki Akimoto, Naotaka Tomioka, Satoko Motai, Yoshio Takahashi   +4 more
wiley   +1 more source

Biomineral crystallographic preferred orientation in Solenogastres molluscs (Aplacophora) is controlled by organic templating

Scientific Reports
Aplacophoran molluscs are shell-less and have a worm-like body which is covered by biomineralized sclerites. We investigated sclerite crystallography and the sclerite mosaic of the Solenogastres species Dorymenia sarsii, Anamenia gorgonophila, and ...
J. D. Castro-Claros, X. Yin, C. Salas, E. Griesshaber, S. Hörl, A. G. Checa, W. W. Schmahl   +6 more
doaj   +1 more source

Source‐to‐sink sediment transport reversals during glacial sea‐level lowstands sustain soil formation on pericoastal carbonate terrains

Sedimentology, EarlyView.
ABSTRACT Understanding the processes that drive soil formation is crucial for developing sustainable land‐use strategies, as changing land‐use practices and climate change exacerbate soil erosion. The formation of substantial arable soils on carbonate bedrock requires substantial dust accretion as the underlying bedrock lacks siliciclastic material. In
Daniel Palchan, Yael Jacobi Glass, Olga Berlin, Yoav Ben Dor   +3 more
wiley   +1 more source

The effects of bioturbation on porewater chemistry and early marine diagenesis: Evidence from a modern intertidal zone in Abu Dhabi, U.A.E.

Sedimentology, EarlyView.
ABSTRACT Early marine carbonate cements generally form in CaCO3‐supersaturated seawater at the seabed or shallow burial depths, resulting in syn‐sedimentary cemented firmgrounds and hardgrounds. The processes controlling early marine diagenesis are complex, particularly in coastal environments where geochemistry is influenced by different water sources
Drew Brown, Tom Kibblewhite, Fiona Whitaker, Daniela Gutierrez‐Rueda, Daniel S. Alessi, John‐Paul Zonneveld, Murray Gingras, Hilary Corlett   +7 more
wiley   +1 more source

Effects of temperature, pH and calcium-to-carbonate ratio on the calcium carbonate polymorphs

Discover Civil Engineering
The precipitation of calcium carbonate (CaCO3) polymorphs (calcite, vaterite, and aragonite) plays a crucial role in tailoring the physicochemical properties of construction materials during mineral carbonation.
Mohd Hanifa, Usha Sharma, P. C. Thapliyal, L. P. Singh   +3 more
doaj   +1 more source

Ocean Acidification in the California Current System [PDF]

Oceanography, 2009
Eastern boundary upwelling systems (EBUS) are naturally more acidic than most of the rest of the surface ocean. Observations of EBUS already show pH values and saturation states with regard to the carbonate mineral aragonite that are as low as those ...
Claudine Hauri, Nicolas Gruber, Gian-Kasper Plattner, Simone Alin, Richard A. Feely, Burke Hales, Patricia A. Wheeler   +6 more
doaj  

The role of river runoff in the Kara Sea surface layer acidification and carbonate system changes

Environmental Research Letters, 2019
This study aims to perform the results of the investigation of the Kara Sea carbonate system (CS) changes and the factors that determine it. The important feature of the Kara Sea water structure is strong stratification caused mainly by the Ob’ and ...
Alexander Polukhin
doaj   +1 more source

Mineralogical characteristics of surface sediment in Sulaibikhat Bay, Kuwait

Kuwait Journal of Science, 2013
Surface sediment samples were collected from 35 locations in Sulaibikhat Bay, Kuwait. Grain sizes, total organic carbon (TOC), carbonate and mineralogical data were determined.
HASSAN ALSHEMMARI, ALI M. AL-DOUSARI, LINA TALEBI, ABDUL NABI AL-GHADBAN   +3 more
doaj  

Synthesis of Aragonite from Precipitated Calcium Carbonate: A Pilot Scale Study

Indonesian Journal of Chemistry
The CO2 mineralization pathway is considered a promising option for carbon capture usage and storage because the captured CO2 can be permanently stored, and secondly industrial waste (i.e., petrochemical refinery, lime, and cement kiln dust) can be ...
Ellyta Sari, Reni Desmiarti, Zulhadjri Zulhadjri, Matlal Fajri Alif, Maulana Yusup Rosadi, Syukri Arief   +5 more
doaj   +1 more source

Identification of cave minerals by Raman spectroscopy: new technology for non-destructive analysis [PDF]

International Journal of Speleology, 2006
The usual tools are X-ray powder diffraction, the optical microscope, and the scanning electron microscope. X-ray diffraction gives a definitive fingerprint by which the mineral can be identified by comparison with a catalog of reference patterns ...
White William B.
doaj