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Related to gneissic: gneissose


A banded or foliated metamorphic rock, usually of the same composition as granite.

[German Gneis, probably alteration of Middle High German ganeist, spark (from its appearance), from Old High German gneista.]

gneiss′ic (nī′sĭk), gneiss′oid′ (nī′soid′), gneiss′ose′ (nī′sōs′) adj.
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References in periodicals archive ?
According to Ab'Saber (1974) a strong erosional process took place in the region during the Tertiary period, exposing the pre-cambrian granitic and gneissic basement of the region and resulting in a degraded (geologically speaking) landscape composed mostly of areas of low altitude.
The older rocks in this massif include the gneissic basement of the Cocha--Rio Tellez Complex and associated meta-sedimentary rocks considered Precambrian and Paleozoic in age (Murcia and Cepeda, 1983; Ponce, 1979).
Raeside and Barr (1990) subdivided these rocks into two assemblages based on metamorphic grade: mainly lower grade units collectively termed the George River metamorphic suite and mainly higher grade and typically gneissic units termed the Bras d'Or metamorphic suite.
Inselbergs are monolithic mountains or groups of mountains that appear abruptly amidst the landscape, consisting mainly of granitic or gneissic rocks (POREMBSKI et al, 1998; POREMBSKI and BARTHLOTT, 2000).
These last authors argued that this distinction is not entirely reliable in discerning between the larger contribution of a granitic versus a gneissic origin, as this depends on factors related to each single pluton.
The occurrence of Sn-W mineralization is controlled by the contact between granite and the gneissic country rock.
Graphite veins can be found in crystalline marbleized limestones associated with granitic and gneissic rocks.