scholarly journals Thermoluminescence Dating: With Special Reference to Accuracy and Reliability of Age Determination Using Quartz of Volcanic Rocks.

1995 ◽  
Vol 34 (3) ◽  
pp. 209-220 ◽  
Author(s):  
Isao Takashima
Keyword(s):  
Special Reference ◽  
Volcanic Rocks ◽  
Age Determination ◽  
Thermoluminescence Dating

Origin of the Tulameen ultramafic-gabbro complex, southern British Columbia

1969 ◽  
Vol 6 (3) ◽  
pp. 399-425 ◽  
Author(s):  
D. C. Findlay
Keyword(s):  
British Columbia ◽  
Internal Structure ◽  
Fractional Crystallization ◽  
Volcanic Rocks ◽  
Age Determination ◽  
Upper Triassic ◽  
Ultramafic Rocks ◽  
Metasedimentary Rocks ◽  
Gabbroic Intrusion

The Tulameen Complex is a composite ultramafic-gabbroic intrusion that outcrops over 22 sq. mi. (57 km2) in the Southern Cordillera of British Columbia. The complex intruded Upper Triassic metavolcanic and metasedimentary rocks of the Nicola Group, and on the basis of geologic relations and a K–Ar age determination (186 m.y.) is tentatively dated as Late Triassic.The principal ultramafic units — dunite, olivine clinopyroxenite, and hornblende clinopyroxenite — form an elongate, non-stratiform body whose irregular internal structure is best explained by deformation contemporaneous with crystallization of the rocks. The derivation of the ultramafic rocks is attributed to fractional crystallization of an ultrabasic magma. The gabbroic mass, which consists of syenogabbro and syenodiorite, partly borders and partly overlies the ultramafic body and was apparently intruded by it.The ultramafic and gabbroic parts of the complex probably formed from separate intrusions of different magmas, but the two suites have sufficient mineralogical and chemical features in common to indicate an ultimate petrogenic affinity of the magmas. Comparison of the Tulameen rocks with nearby intrusions of the same general age, in particular the Copper Mountain stock, suggests that they are members of a regional suite of alkalic intrusions. The possibility is also raised that these intrusions may be comagmatic with the Nicola volcanic rocks.

Thermoluminescence Dating of Coarse-Grain Quartz from the Malan Loess at Zhaitang Section, China

1987 ◽  
Vol 28 (3) ◽  
pp. 356-363 ◽  
Author(s):  
Lu Yanchou ◽  
A. J. Mortlock ◽  
D. M. Price ◽  
M. L. Readhead
Keyword(s):  
Age Determination ◽  
Total Sample ◽  
Coarse Grain ◽  
Annual Dose ◽  
Fine Grain ◽  
Malan Loess ◽  
Thermoluminescence Dating ◽  
Beijing China ◽  
Good Agreement

AbstractThermoluminescence (TL) ages were obtained for five loess samples taken from the Zhaitang section near Beijing, China, using the coarse-grain quartz technique. The paleodose values have been determined by the method of total sample bleaching and regeneration of the TL growth curve. The method appears to be suitable for the age determination of loess samples up to about 150,000 yr where the annual dose-rate values are of the order 3–4 mGy/yr. This limit is a function of the total accumulated dose. The ages are in good agreement with those obtained by a fine-grain TL technique and are consistent with geological and geomagnetostratigraphic evidence.

The petrology of the basic and intermediate rocks of upper Swat, Pakistan

1973 ◽  
Vol 110 (3) ◽  
pp. 285-300 ◽  
Author(s):  
M. Qasim Jan ◽  
D. R. C. Kempe
Keyword(s):  
Volcanic Rocks ◽  
Age Determination ◽  
Tholeiitic Basalt ◽  
Amphibolite Facies ◽  
Igneous Rocks ◽  
Basalt Magma ◽  
Chemical Analyses

SummaryA series of metamorphosed (amphibolite facies) basic and intermediate igneous rocks from upper Swat, Pakistan, is described, with seven chemical analyses. The rocks intrude ?Palaeozoic metasediments and are partially bordered by other, later, intrusive and volcanic rocks. The group, now represented by, from S–N, epidote amphibolites, amphibolites, noritic and hypersthene gabbros, and quartz diorites, is considered to be derived from a series of plagioclase hypersthenites, norites, hypersthene gabbros, and hypersthene diorites. Variation diagrams are used to show that the series forms a differentiated sequence; FMA and lime-alkali diagrams suggest that it is similar to the rocks of the Garabal Hill–Loch Fyne area of Scotland. Some of the mineralogy of the group is briefly discussed, with five chemical analyses. A K/Ar age determination gives 67 Ma; thus the rocks probably derive from an early Himalayan (Alpine) tholeiitic basalt magma.

scholarly journals K-Ar age determination of Late Pleistocene volcanic rocks.

1984 ◽  
Vol 90 (12) ◽  
pp. 899-909 ◽  
Author(s):  
TETSUMARU ITAYA ◽  
KEISUKE NAGAO ◽  
HIROTSUGU NISHIDO ◽  
KOREICHI OGATA
Keyword(s):  
Late Pleistocene ◽  
Volcanic Rocks ◽  
Age Determination

Age of volcanic rocks and syndepositional iron formations, Marquette Range Supergroup: implications for the tectonic setting of Paleoproterozoic iron formations of the Lake Superior region

2002 ◽  
Vol 39 (6) ◽  
pp. 999-1012 ◽  
Author(s):  
D A Schneider ◽  
M E Bickford ◽  
W F Cannon ◽  
K J Schulz ◽  
M A Hamilton
Keyword(s):  
Lake Superior ◽  
Tectonic Setting ◽  
Volcanic Rocks ◽  
Age Determination ◽  
Iron Formation ◽  
Continental Rifting ◽  
The South ◽  
Zircon Age ◽  
Iron Formations ◽  
Northern Michigan

A rhyolite in the Hemlock Formation, a mostly bimodal submarine volcanic deposit that is laterally correlative with the Negaunee Iron-formation, yields a sensitive high-resolution ion microprobe (SHRIMP) U–Pb zircon age of 1874 ± 9 Ma, but also contains inherited Archean zircons as old as 3.8 Ga. This precise age determination for the classic Paleoproterozoic stratigraphic sequence of northern Michigan, the Marquette Range Supergroup (MRS), necessitates modification of previous depositional and tectonic models. Our new data indicate that the Menominee Group, previously ascribed to continental rifting during early, pre-collision phases of the Penokean orogenic cycle, is coeval with arc-related volcanic rocks now preserved as accreted terranes immediately to the south and is more aptly interpreted as a foredeep deposit. We interpret these to be second-order basins created by oblique subduction of the continental margin rather than basins formed on a rifting margin. Along with a recently reported age for the Gunflint Formation in Ontario of 1878 ± 2 Ma, our data suggest that an extensive foredeep in the western Lake Superior region was the locus of iron-formation deposition during arc accretion from the south. Further, we interpret the lower MRS (Chocolay Group), a glaciogenic and shallow-marine succession that lies atop Archean basement, to be equivalent to the upper part of the Huronian Supergroup of Ontario and to represent the original continental rifting and passive-margin phase of the Penokean cycle. The upper MRS (Baraga Group) represents deeper marine basins, dominated by turbidites and lesser volcanic rocks, resulting from increased subsidence and continued collision. A stitching pluton, which cuts correlatives of the Hemlock Formation in a thrust sheet, yielded a U–Pb zircon age of 1833 ± 6 Ma, consistent with other post-tectonic plutons in Wisconsin and northern Michigan, indicating that Penokean convergence lasted no longer than ~40 million years.

scholarly journals Thermoluminescence dating of Pleistocene volcanic rocks and pumice flow deposits in Onikobe-Naruko and adjacent areas, NE Japan

2006 ◽  
Vol 35 (2) ◽  
pp. 70-77 ◽  
Author(s):  
Isao TAKASHIMA ◽  
Hideki MURAKAMI ◽  
Duk-Geun HONG ◽  
I G.B. EDDY SUCIPTA ◽  
Youji MOURI ◽  
...  
Keyword(s):  
Volcanic Rocks ◽  
Thermoluminescence Dating ◽  
Pumice Flow ◽  
Ne Japan

ABSOLUTE AGE OF THE FISSET BROOK FORMATION AND THE DEVONIAN-MISSISSIPPIAN BOUNDARY, CAPE BRETON ISLAND, NOVA SCOTIA

1964 ◽  
Vol 1 (3) ◽  
pp. 159-166 ◽  
Author(s):  
R. F. Cormier ◽  
A. M. Kelly
Keyword(s):  
Nova Scotia ◽  
Volcanic Rocks ◽  
Age Determination ◽  
Cape Breton Island ◽  
Rock Samples ◽  
Cape Breton ◽  
Absolute Age ◽  
Age Determinations ◽  
Good Agreement

The Fisset Brook formation of sedimentary and volcanic rocks crops out in the Cheticamp area of Cape Breton Island, Nova Scotia. Its stratigraphic age has been determined as earliest Mississippian using spores contained in the sedimentary members. A rubidium–strontium age determination using whole-rock samples of the volcanic members has yielded an age of 349 ± 15 million years. This is in good agreement with age determinations elsewhere for the Devonian–Mississippian boundary. Similar rocks exposed to the east of Lake Ainslie, some thirty miles to the southwest, give an identical age, 348 ± 20 million years. These rocks are clearly correlative with the Fisset Brook formation. Mixed sedimentary and volcanic rocks in the Cape St. Lawrence area, some thirty miles to the northeast of Fisset Brook, appear to be significantly older, 462 ± 25 million years, and should be considered tentatively as Ordovician in age.

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