Changes in the physical and chemical properties of biogenic silica from the central equatorial Pacific; Part III, Specific pore volume, mean pore size, and skeletal ultrastructure of acid-cleaned samples

Possible mechanism of structural incorporation of Al into diatomite during the deposition process I. Via a condensation reaction of hydroxyl groups

“…Because the existence of Al in the structure of diatomite is demonstrated to effectively lower the solubility of diatomaceous silica and is beneficial to the preservation of diatomite [13][14][15][16][17], many studies focus on the properties of structural Al in diatomite, such as its content and coordination number (tetrahedral or octahedral coordination) [18][19][20][21][22]. In addition, researchers have estimated the transport of Al from the oceans' surface to the sediment [23][24][25] by studying the structural Al in diatomite.…”

Differential diatom dissolution in Late Quaternary sediments from Lake Manyara, Tanzania: an experimental approach

“…Conversely, Lewin found that the addition of metal cations, especially iron and aluminium, to her solutions caused a marked reduction in the rate of dissolution, possibly through adsorption to the silica frustule surfaces. The specific surface area of diatoms and radiolarian rich marine sediments has been shown by Hurd et al (1981) and Hurd & Birdwhistell (1983) to significantly influence the rate of dissolution. This offers an explanation for the differential dissolution of marine diatom assemblages in sea water found in experiments by Mikkelsen (1980), Shemesh et al (1989, and Pinchon et al (1992).…”

Experimental diatom dissolution and the quantification of microfossil preservation in sediments

“…Previous experimental work has quantified amorphous silica dissolution in solutions that vary in pH, temperature, salt concentration and ionic composition (e.g. Lewin 1961;Marshall and Warakomski 1980;Hurd et al 1981;Barker et al 1994). Kinetic rates of dissolution are related to the degree of saturation of the dissolving medium (and are non-linear at high undersaturation; van Cappellen and Qiu, 1997).…”

“…Kinetic rates of dissolution are related to the degree of saturation of the dissolving medium (and are non-linear at high undersaturation; van Cappellen and Qiu, 1997). Factors intrinsic to the silica solid are also important, notably the surface area of reactive solid per unit mass (the specific surface area) and the total area available for dissolution per unit volume of solution (Hurd et al, 1981). Dissolution rates are also sensitive to organic matter and metal ions associated with the frustule surface (Lewin 1961;van Bennekom, 1980;Mayer et al 1991).…”