Actinolitic

Related to Actinolitic: tremolite, epidote

Ac`tin`o`lit´ic


a.1.(Min.) Of the nature of, or containing, actinolite.
References in periodicals archive ?
Analysed amphiboles show edenitic, pargasitic, and actinolitic compositions.
The scapolite metagabbro is dominated by a Cl-rich marialitic scapolite ([Me.sub.19-42]) and edenitic, pargasitic, and actinolitic amphibole (Mg# = 0.79-0.87; Cl < 0.24 a.p.f.u.), and it locally contains a high phlogopite content (Mg# < 0.95) (Figures 4(a)-4(b)).
Occasional fragments of actinolitic schists exhibited susceptibility values of 24 000 - 47 500.[10.sup.-6] SI at the maximum of 300 nT.
Population 2 amphibole is best classified as hornblende or actinolitic hornblende with [greater than or equal to] 1 Al per unit formula.
Two types of amphibole are present, an earlier generation of magnesio-hornblende with greenish brown-brown-tan pleochroism and later pale green-green actinolitic hornblende.
Important relationships seen at both macroscopic and microscopic scales include (1) rocks of the shear zone have undergone polymetamorphism, (2) an earlier phase of actinolitic amphibole (greenschist facies) is replaced in areas by a later phase of hornblendic amphibole (amphibolite facies), (3) zones of high strain correlate with rocks with a larger amount of hornblende, and (4) zones of lower strain correlate with rocks with a larger amount of porphyroclastic actinolite, surrounded by significant amounts of hornblende.
Most amphibole grains are zoned, with medium green actinolitic cores and dark blue-green hornblende rims, and newly formed hornblende is present in the matrix.
A second trend defining a positive slope toward amphiboles poorer in Ti and Al at lower Fe/(Fe+Mg) values and projecting away from the magmatic trend is formed by actinolitic hornblende, which suggests that it represents a secondary (sub-solidus) alteration trend.
Plagioclase is partly altered to saussurite and sericite, and pyroxene is variably altered to pale brown and pale green actinolitic amphibole, chlorite, and epidote.