Goldich dissolution series

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The Goldich dissolution series is a method of predicting the relative stability or weathering rate of common igneous minerals on the Earth's surface, with minerals that form at higher temperatures and pressures less stable on the surface than minerals that form at lower temperatures and pressures.

Contents

Discontinuous
Series		Continuous
Series		High
Olivine Plagioclase
(Calcium rich)
Pyroxene
Amphibole
Biotite
(Black Mica)		 Plagioclase
(Sodium rich)		Relative
Weathering
potential
Orthoclase
Muscovite
(White Mica)
Quartz
Low

Chemical weathering processes

S. S. Goldich derived this series in 1938 after studying soil profiles and their parent rocks. [1] Based on sample analysis from a series of weathered localities, Goldich determined that the weathering rate of minerals is controlled at least in part by the order in which they crystallize from a melt. This order meant that the minerals that crystallized first from the melt were the least stable under earth surface conditions, while the minerals that crystallized last were the most stable. This is not the only control on weathering rate; this rate is dependent on both intrinsic (qualities specific to the minerals) and extrinsic (qualities specific to the environment) variables. [1] [2] Climate is a key extrinsic variable, controlling the water to rock ratio, pH, and alkalinity, all of which impact the rate of weathering. [1] The Goldich dissolution series concerns intrinsic mineral qualities, which were proven both by Goldich as well as preceding scientists to also be important for constraining weathering rates.

Earlier work by Steidtmann [3] demonstrated that the order of ionic loss of a rock as it weathers is: CO32-, Mg2+, Na+, K+, SiO2−, Fe2+/3+, and finally Al3+. Goldich furthered this analysis by noting the relative mineral stability order, which is related to the relative resistance of these ions to leaching. Goldich notes that overall, mafic (rich in iron and magnesium) minerals are less stable than felsic (rich in silica) minerals. The order of stability in the series echoes Bowen's reaction series very well, leading Goldich to suggest that the relative stability at the surface is controlled by crystallization order. [4]

While Goldich’s original order of mineral weathering potential was qualitative, later work by Michal Kowalski and J. Donald Rimstidt placed in the series in quantitative terms. Kowalski and Rimstidt performed an analysis of mechanical and chemical grain weathering, and demonstrated that the average lifetime of chemically weathered detrital grains quantitatively fit the Goldich sequence extremely well. [5] This helped to supplement the real-world applicability of the dissolution series. The difference in chemical weathering time can span millions of years. For example, quickest to weather of the common igneous minerals is apatite, which reaches complete weathering in an average of 105.48 years, and slowest to weather is quartz, which weathers fully in 108.59 years. [5]

Bowen's reaction series

The Goldich dissolution series follows the same pattern of the Bowen's reaction series, with the minerals that are first to crystallize also the first the undergo chemical weathering. [4] The Bowen’s reaction series dictates that during fractional crystallization, olivine and Ca-plagioclase feldspars are the first to crystalize out of a melt, after which follows pyroxene, amphibole, biotite, Na-plagioglase, orthoclase feldspar, muscovite, and finally, quartz. This order is controlled by the temperature of the melt and its composition. Because earlier crystallizing minerals are more stable at higher temperatures and pressures, these weather the fastest under surface conditions.

Saponite is a common weathering product of ultramafic and mafic rocks. It is found in high-pH evaporite lakes and in association with basalts or serpentines. Chamosite, Saponite, Copper-188771.jpg
Saponite is a common weathering product of ultramafic and mafic rocks. It is found in high-pH evaporite lakes and in association with basalts or serpentines.

Common secondary minerals

Chemical weathering of igneous minerals leads to the formation of secondary minerals, which constitute the weathering products of the parent minerals. Secondary weathering minerals of igneous rocks can be classified mainly as iron oxides, salts, and phyllosilicates. The chemistry of the secondary minerals is controlled in part by the chemistry of the parent rock. Mafic rocks tends to contain higher proportions of magnesium and ferric and ferrous iron, which can lead to secondary minerals high in abundance of these cations, [6] including serpentine, Al-, Mg- and Ca-rich clays, [7] and iron oxides such as hematite. [6] Felsic rocks tends to have relatively higher proportions of potassium and sodium, which can lead to secondary minerals rich in these ions, including Al-, Na- and K-rich clays such as kaolinite, [8] montmorillonite [8] and illite. [9]

Olivine weathering to iddingsite within a mantle xenolith, a common reaction within the series Iddingsite.JPG
Olivine weathering to iddingsite within a mantle xenolith, a common reaction within the series

Application to soil profiles

The Goldich dissolution series can be applied to Lithosequences, which are a way characterizing of a soil profile based on its parent material. [10] Lithosequences include soils that have undergone relatively similar weathering conditions, so variations in composition are based on the relative weathering rates of parent minerals. Therefore, the weathering rates of these soils and their compositions are primarily influenced by the relative proportion of minerals in the Goldich dissolution series. [10]

Limitations

Experimental work by White and Brantley (2003) highlighted some of the limitations of the Goldich dissolution series, most notably that some variations in weathering rates of different minerals are not as pronounced as Goldich argues. [2] According to the Goldich dissolution series,  anorthite, a plagioclase feldspar, should weather quickly, with a lifetime of 105.62 years quantified by Kowalski and Rimstidt. [1] [5] Conversely, the lifetime of K-feldspar should be much longer, at 108.53 years based again on Kowalski and Rimstidt’s work. However, White and Brantley’s experimental results demonstrate that the relative weathering rates of K-feldspar and plagioclase feldspar are quite similar, and mainly moderated by the extent to which the minerals had already been weathered (in an exponentially decreasing function). This demonstrates that the Goldich series may not apply across all kinds of weathering processes, and likewise does not take into account the effect of exponential decay in weathering rate of a surface. [2]

Related Research Articles

In geology, felsic is a modifier describing igneous rocks that are relatively rich in elements that form feldspar and quartz. It is contrasted with mafic rocks, which are relatively richer in magnesium and iron. Felsic refers to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. Felsic magma or lava is higher in viscosity than mafic magma/lava.

<span class="mw-page-title-main">Granite</span> Common type of intrusive, felsic, igneous rock with granular structure

Granite is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions. These range in size from dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers.

<span class="mw-page-title-main">Mafic</span> Silicate mineral or igneous rock that is rich in magnesium and iron

A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include basalt, diabase and gabbro. Mafic rocks often also contain calcium-rich varieties of plagioclase feldspar. Mafic materials can also be described as ferromagnesian.

<span class="mw-page-title-main">Sandstone</span> Type of sedimentary rock

Sandstone is a clastic sedimentary rock composed mainly of sand-sized silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks.

<span class="mw-page-title-main">Feldspar</span> Group of rock-forming minerals

Feldspars are a group of rock-forming aluminium tectosilicate minerals, also containing other cations such as sodium, calcium, potassium, or barium. The most common members of the feldspar group are the plagioclase (sodium-calcium) feldspars and the alkali (potassium-sodium) feldspars. Feldspars make up about 60% of the Earth's crust, and 41% of the Earth's continental crust by weight.

Geochemistry is the science that uses the tools and principles of chemistry to explain the mechanisms behind major geological systems such as the Earth's crust and its oceans. The realm of geochemistry extends beyond the Earth, encompassing the entire Solar System, and has made important contributions to the understanding of a number of processes including mantle convection, the formation of planets and the origins of granite and basalt. It is an integrated field of chemistry and geology.

<span class="mw-page-title-main">Plagioclase</span> Type of feldspar

Plagioclase is a series of tectosilicate (framework silicate) minerals within the feldspar group. Rather than referring to a particular mineral with a specific chemical composition, plagioclase is a continuous solid solution series, more properly known as the plagioclase feldspar series. This was first shown by the German mineralogist Johann Friedrich Christian Hessel (1796–1872) in 1826. The series ranges from albite to anorthite endmembers (with respective compositions NaAlSi3O8 to CaAl2Si2O8), where sodium and calcium atoms can substitute for each other in the mineral's crystal lattice structure. Plagioclase in hand samples is often identified by its polysynthetic crystal twinning or 'record-groove' effect.

<span class="mw-page-title-main">Anorthite</span> Calcium-rich feldspar mineral

Anorthite is the calcium endmember of the plagioclase feldspar mineral series. The chemical formula of pure anorthite is CaAl2Si2O8. Anorthite is found in mafic igneous rocks. Anorthite is rare on the Earth but abundant on the Moon.

<span class="mw-page-title-main">Andesite</span> Type of volcanic rock

Andesite is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predominantly of sodium-rich plagioclase plus pyroxene or hornblende.

<span class="mw-page-title-main">Anorthosite</span> Mafic intrusive igneous rock composed predominantly of plagioclase

Anorthosite is a phaneritic, intrusive igneous rock characterized by its composition: mostly plagioclase feldspar (90–100%), with a minimal mafic component (0–10%). Pyroxene, ilmenite, magnetite, and olivine are the mafic minerals most commonly present.

Within the field of geology, Bowen's reaction series is the work of the Canadian petrologist Norman L. Bowen, who summarized, based on experiments and observations of natural rocks, the sequence of crystallization of common silicate minerals from typical basaltic magma undergoing fractional crystallization. Bowen's reaction series is able to explain why certain types of minerals tend to be found together while others are almost never associated with one another. He experimented in the early 1900s with powdered rock material that was heated until it melted and then allowed to cool to a target temperature whereupon he observed the types of minerals that formed in the rocks produced. He repeated this process with progressively cooler temperatures and the results he obtained led him to formulate his reaction series which is still accepted today as the idealized progression of minerals produced by cooling basaltic magma that undergoes fractional crystallization. Based upon Bowen's work, one can infer from the minerals present in a rock the relative conditions under which the material had formed.

Restite is the residual material left at the site of melting during the in place production of granite through intense metamorphism.

<span class="mw-page-title-main">Cumulate rock</span>

Cumulate rocks are igneous rocks formed by the accumulation of crystals from a magma either by settling or floating. Cumulate rocks are named according to their texture; cumulate texture is diagnostic of the conditions of formation of this group of igneous rocks. Cumulates can be deposited on top of other older cumulates of different composition and colour, typically giving the cumulate rock a layered or banded appearance.

In geology, igneous differentiation, or magmatic differentiation, is an umbrella term for the various processes by which magmas undergo bulk chemical change during the partial melting process, cooling, emplacement, or eruption. The sequence of magmas produced by igneous differentiation is known as a magma series.

<span class="mw-page-title-main">Clastic rock</span> Sedimentary rocks made of mineral or rock fragments

Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus, chunks, and smaller grains of rock broken off other rocks by physical weathering. Geologists use the term clastic to refer to sedimentary rocks and particles in sediment transport, whether in suspension or as bed load, and in sediment deposits.

<span class="mw-page-title-main">Fractional crystallization (geology)</span> Process of rock formation

Fractional crystallization, or crystal fractionation, is one of the most important geochemical and physical processes operating within crust and mantle of a rocky planetary body, such as the Earth. It is important in the formation of igneous rocks because it is one of the main processes of magmatic differentiation. Fractional crystallization is also important in the formation of sedimentary evaporite rocks.

This glossary of geology is a list of definitions of terms and concepts relevant to geology, its sub-disciplines, and related fields. For other terms related to the Earth sciences, see Glossary of geography terms.

<span class="mw-page-title-main">Igneous rock</span> Rock formed through the cooling and solidification of magma or lava

Igneous rock, or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rock is formed through the cooling and solidification of magma or lava.

S-type granites are a category of granites first proposed in 2001. They are recognized by a specific set of mineralogical, geochemical, textural, and isotopic characteristics. S-type granites are over-saturated in aluminium, with an ASI index greater than 1.1 where ASI = Al2O3 / (CaO + Na2O +K2O) in mol percent; petrographic features are representative of the chemical composition of the initial magma as originally put forth by Chappell and White are summarized in their table 1.

I-type granites are a category of granites originating from igneous sources, first proposed by Chappell and White (1974). They are recognized by a specific set of mineralogical, geochemical, textural, and isotopic characteristics that indicate, for example, magma hybridization in the deep crust. I-type granites are saturated in silica but undersaturated in aluminum; petrographic features are representative of the chemical composition of the initial magma. In contrast S-type granites are derived from partial melting of supracrustal or "sedimentary" source rocks.

References

  1. 1 2 3 4 Goldich, Samuel S. (1938). "A Study in Rock-Weathering". The Journal of Geology. 46 (1): 17–58. Bibcode:1938JG.....46...17G. doi:10.1086/624619. ISSN   0022-1376. S2CID   128498195.
  2. 1 2 3 White, Art F; Brantley, Susan L (2003). "The effect of time on the weathering of silicate minerals: why do weathering rates differ in the laboratory and field?". Chemical Geology. Controls on Chemical Weathering. 202 (3): 479–506. Bibcode:2003ChGeo.202..479W. doi:10.1016/j.chemgeo.2003.03.001. ISSN   0009-2541.
  3. ↑ Steidtmann, Edward (1908). "A graphic comparison of the alteration of rocks by weathering with their alteration by hot solutions". Economic Geology. 3 (5): 381–409. doi:10.2113/gsecongeo.3.5.381. ISSN   0361-0128.
  4. 1 2 Bowen, N. L. (1956). The Evolution of the Igneous Rocks. Canada: Dover. pp. 60–62.
  5. 1 2 3 Kowalewski, Michał; Rimstidt, J. Donald (2003). "Average Lifetime and Age Spectra of Detrital Grains: Toward a Unifying Theory of Sedimentary Particles". The Journal of Geology. 111 (4): 427–439. Bibcode:2003JG....111..427K. doi:10.1086/375284. ISSN   0022-1376. S2CID   129172662.
  6. 1 2 Siever, Raymond; Woodford, Norma (1979). "Dissolution kinetics and the weathering of mafic minerals". Geochimica et Cosmochimica Acta. 43 (5): 717–724. Bibcode:1979GeCoA..43..717S. doi:10.1016/0016-7037(79)90255-2. ISSN   0016-7037.
  7. ↑ Meunier, Alan (2005). Clays. France: Springer. p. 265. ISBN   3-540-21667-7.
  8. 1 2 Stoch, Leszek; Sikora, Wanda (1976). "Transformations of Micas in the Process of Kaolinitization of Granites and Gneisses". Clays and Clay Minerals. 24 (4): 156–162. Bibcode:1976CCM....24..156S. doi:10.1346/CCMN.1976.0240402. ISSN   1552-8367. S2CID   51812008.
  9. ↑ Sequeira Braga, M. A; Paquet, H; Begonha, A (2002). "Weathering of granites in a temperate climate (NW Portugal): granitic saprolites and arenization". CATENA. 49 (1): 41–56. doi:10.1016/S0341-8162(02)00017-6. ISSN   0341-8162.
  10. 1 2 White, Art F. (1995), "Chapter 9. CHEMICAL WEATHERING RATES OF SILICATE MINERALS IN SOILS", Chemical Weathering Rates of Silicate Minerals, De Gruyter, pp. 407–462, doi:10.1515/9781501509650-011, ISBN   9781501509650 , retrieved 2021-10-28
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