TY - JOUR
T1 - A Grenville-age layered intrusion in the subsurface of west Texas
T2 - petrology, petrography, and possible tectonic setting
AU - Kargi, H.
AU - Barnes, C. G.
PY - 1995
Y1 - 1995
N2 - The Nellie intrusion is a thick (more than 4420 m) mafic to ultramafic layered intrusion with a radiometric age of ~1163 Ma. Rock types change abruptly with stratigraphic height and include norite, pyroxenite, gabbronorite, hornblende gabbro, gabbro, anorthosite, harzburgite, and lherzolite. The general order of crystallization was olivine, orthopyroxene, plagioclase + clinopyroxene, and hornblende. Eleven cyclic units were identified on the basis of evidence for injection of basaltic magma; these can be grouped into three-megacyclic units. Although the intrusion is approximately coeval with Keweenawan magmatism and with emplacement of diabasic dikes in western North America, it is dissimilar in detail to both suites of rocks. Nevertheless, its composition and geophysical setting are consistent with emplacement in an extensional tectonic environment. -from Authors
AB - The Nellie intrusion is a thick (more than 4420 m) mafic to ultramafic layered intrusion with a radiometric age of ~1163 Ma. Rock types change abruptly with stratigraphic height and include norite, pyroxenite, gabbronorite, hornblende gabbro, gabbro, anorthosite, harzburgite, and lherzolite. The general order of crystallization was olivine, orthopyroxene, plagioclase + clinopyroxene, and hornblende. Eleven cyclic units were identified on the basis of evidence for injection of basaltic magma; these can be grouped into three-megacyclic units. Although the intrusion is approximately coeval with Keweenawan magmatism and with emplacement of diabasic dikes in western North America, it is dissimilar in detail to both suites of rocks. Nevertheless, its composition and geophysical setting are consistent with emplacement in an extensional tectonic environment. -from Authors
UR - http://www.scopus.com/inward/record.url?scp=0029542851&partnerID=8YFLogxK
U2 - 10.1139/e95-168
DO - 10.1139/e95-168
M3 - Article
AN - SCOPUS:0029542851
VL - 32
SP - 2159
EP - 2166
JO - Canadian Journal of Earth Sciences
JF - Canadian Journal of Earth Sciences
SN - 0008-4077
IS - 12
ER -