The REE's mineralogy is very coarse and is found mainly in igneous rocks of subalkaline
to alkaline tendency (sienites, quartzites, quartz monzonites).
Major element analysis finds out that Tobra Formation sandstone are lithic-arenite and non-marine deposits with increasing maturity and subalkaline
, basic to acidic rocks.
To the south of the Echassieres granitic complex, another type of intrusion of biotite porphyritic subalkaline
granite (Pouzol-Servant) is emplaced at ca.
Magmatic affinity of modern and ancient subalkaline
volcanic rocks determined from trace-element discriminant diagrams.
Briefly, the soil was moderately subalkaline
(0-30 cm) with a clay texture according to United States Department of Agriculture classification ; it was characterized by low electrical conductivity (EC), cation exchange capacity (CEC), and nitrogen and carbon content; it is unlikely that this soil already contained charcoal as there had been no tradition of crop residue or other burning on the land.
By using the Irvine and Baragar (1971) boundary line, it is clear that the samples have a subalkaline
affinity (Figure 3b).
The dolerite sills that intruded Silurian shales in the Baltic Sedimentary Basin are fractionated subalkaline
rocks of within-plate affinity, as is also clear from their setting in a continental basin.
The late-Variscan mafic rocks from central Spain develop well-characterised medium--to high-K calc-alkaline trends (Villaseca et al., 2004; Orejana et al., 2009; Scarrow et al., 2009), with the most primitive gabbros showing orthopyroxene (typically subalkaline
) as a near liquidus phase.
Geochemistry of subalkaline
and alkaline extrusives from the Kermanshah ophiolite, Zagros Suture Zone, western Iran: implications on Tethyan plate tectonics.
According to [R.sub.1]-[R.sub.2] discrimination diagram  and the classification diagram for plutonic rocks , the Chah Anjir intrusive rocks can be classified as diorite, monzodiorite (Figure 7(a)), and diorite to syenodiorite, respectively (Figure 7(b)), with subalkaline
to alkaline affinity (Figure 8(a)).
But in the case of initial pH values greater than 2, the final pH increased to subalkaline
or alkaline values for both the clay and micelleclay systems.