Hornblende gabbro is an intrusive rock similar to normal gabbro (gabbro sensu stricto[1]). In the QAPF classification it falls within the gabbro field, in which quartz makes up 0% to 5% of the QAPF mineral fraction, plagioclase makes up 90% or more of the total feldspar content, and the plagioclase is calcium-rich (%An > 50).[2][3] Hornblende gabbro is distinguished from other subtypes of gabbro by having a composition almost entirely of plagioclase and hornblende, with olivine and pyroxene each making up less than 5% of its mineral content.[1]
^ ab"Rock Classification Scheme - Vol 1 - Igneous" (PDF). British Geological Survey: Rock Classification Scheme. 1: 1–52. 1999.
^Le Bas, M. J.; Streckeisen, A. L. (1991). "The IUGS systematics of igneous rocks". Journal of the Geological Society. 148 (5): 825–833. Bibcode:1991JGSoc.148..825L. CiteSeerX 10.1.1.692.4446. doi:10.1144/gsjgs.148.5.0825. S2CID 28548230.
^Philpotts, Anthony R.; Ague, Jay J. (2009). Principles of igneous and metamorphic petrology (2nd ed.). Cambridge, UK: Cambridge University Press. pp. 139–143. ISBN 978-0-521-88006-0.
Hornblendegabbro is an intrusive rock similar to normal gabbro (gabbro sensu stricto). In the QAPF classification it falls within the gabbro field, in...
includes hornblende. Gabbroids form a family of rock types similar to gabbro, such as monzogabbro, quartz gabbro, or nepheline-bearing gabbro. Gabbro itself...
Hornblende is a complex inosilicate series of minerals. It is not a recognized mineral in its own right, but the name is used as a general or field term...
Bojite is a variety of gabbro characterized by the presence of plagioclase feldspar and primary hornblende and absence of clinopyroxene typically associated...
half of the hogbacks, by foliated biotite-hornblende tonalite and on the southern half by hornblendegabbro. The basalt is potassium-argon dated to 10...
pyrrhotite, and hercynitic spinel. The main texture in the gabbro is ophitic to sub-ophitic, but hornblende and plagioclase are subhedral to anhedral grains. Plagioclase...
silica-poor igneous rocks which are part of the Glen Loy Complex. This hornblendegabbro and diorite was intruded during the Silurian period in the course...
granular aggregates of clear green hornblende: in fact the original structure disappears. In Norway scapolite-hornblende rocks have long been known at Ødegården...
andesine), biotite, hornblende, and sometimes pyroxene. The chemical composition of diorite is intermediate, between that of mafic gabbro and felsic granite...
massive-gabbro- and layered-gabbro-derived amphibolites Ultra-Mafic Rocks (intruded by dikes and lenses of diorite rocks, olivine gabbro, and hornblende-gabbro...
appinites are reported from Canada, for instance from the Frog Lake hornblendegabbro situated within the late neoproterozoic Avalon Terrane in Nova Scotia...
layered gabbro and pyroxenite occur structurally above the ultramafic section and are cut by dikes that vary in composition from hornblendegabbro to diorite...
Lava Formation, primarily consists of hornblende tonalite. Pendants of quartz-norite to quartz-hornblendegabbro are present in the roof of the tonalite...
about 50 m by 600 m and trends east-west, grading into garnet-bearing meta-gabbro to the east. To the south of the garnet amphibolite is a fault that runs...
stocks, laccoliths, sills and dikes. Common intrusive rocks are granite, gabbro, or diorite. The central cores of major mountain ranges consist of intrusive...
allied to this group are the hornblendites, consisting essentially of hornblende and other amphiboles. They are essentially of igneous origin, though some...
diorites, and gabbros. Moreover, the effusive andesites do not always correspond to the plutonic diorites but partly also to the gabbros. As the different...
(/æmˈfɪbəlaɪt/) is a metamorphic rock that contains amphibole, especially hornblende and actinolite, as well as plagioclase feldspar, but with little or no...
rock Hornblendite – Plutonic rock consisting mainly of the amphibole hornblende Hyaloclastite – Volcaniclastic accumulation or breccia Icelandite – Igneous...
pyroxene and hornblende in a clear matrix of feldspar: these centric structures are frequent in granulites. The rocks of this group accompany gabbro and serpentine...
intrusive material, norite and gabbro. The norite shifts from hypersthene to augite while the gabbro has abundant augite, hornblende and quartz. The tonalite...
emplaced after the faulting and folding of Huronian rocks, and are hornblendegabbro of tholeiitic basalt composition.: 25 In the Sudbury–Elliot Lake...
surrounding the Roseland anorthosite. hornblende nelsonite gabbro-nelsonite: a rock intermediate in composition between gabbro and nelsonite The prefixes ilmenite...
North Cascades Topo map USGS Pinnacle Mountain Geology Type of rock Hornblendegabbro Climbing First ascent September 11, 1940 Easiest route class 2 scrambling...
feldspar and quartz with scattered darker biotite mica and amphibole (often hornblende) peppering the lighter color minerals. Occasionally some individual crystals...
composition between hornblende-biotite tonalite to granodiorite, with lateral variations between gabbro to granite. Common minerals are hornblende, quartz, plagioclase...
Global Information