THREE-DIMENSIONAL MEASUREMENT OF COLUMNAR JOINTING IN THE BISHOP TUFF, OWENS RIVER GORGE, CALIFORNIA

2017 ◽  
Author(s):  
Antonio M. Bird ◽  
◽  
Katherine A. Kelker ◽  
Elizabeth S. Brogden ◽  
Jeff Glazner ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Bishop Tuff ◽  
Columnar Jointing ◽  
Dimensional Measurement ◽  
Three Dimensional Measurement

Gemini-Induced Columnar Jointing in Vitreous Ice. Cryo-HRSEM as a Tool for Discovering New Colloidal Morphologies

2002 ◽  
Vol 124 (7) ◽  
pp. 1140-1141 ◽  
Author(s):  
Fredric M. Menger ◽  
Hong Zhang ◽  
Kevin L. Caran ◽  
Victor A. Seredyuk ◽  
Robert P. Apkarian
Keyword(s):  
Columnar Jointing

scholarly journals The Polychnitos ignimbrite of Lesvos island

2001 ◽  
Vol 34 (3) ◽  
pp. 917 ◽  
Author(s):  
S. LAMERA ◽  
K. ST. SEYMOUR ◽  
C. VAMVOUKAKIS ◽  
M. KOULl ◽  
E. PARASKEVAS ◽  
...  
Keyword(s):  
Mineral Assemblage ◽  
Elevated Temperatures ◽  
Magma Mixing ◽  
Volcanic Rocks ◽  
Late Paleozoic ◽  
Lithic Clast ◽  
The West ◽  
Columnar Jointing ◽  
Metamorphic Basement ◽  
Ignimbrite Sheet

Miocene volcanism on Lesvos was particularly explosive giving rise to two extensive pyroclastic formations, the Sigri pyroclastics to the west and the Polychnitos ignimbrite to the east of the island. The Polychnitos ignimbrite at 17.2±0.5 Ma (Borsi et al.1972) is part of the shoshonitic succession on Lesbos which ranges in composition from basalt to rhyolite and is both underlain and overlain by calcalkaline volcanic rocks (Pe-Piper and Piper 1993) resting on a late Paleozoic metamorphic basement which has acted as an impediment to the free flow of the ignimbrite. The Polychnitos ignimbrite consists of eight lithological units, six of which are presumed to be facies of the same ignimbrite sheet ("PK", "PU", "MGF I, II, III", "Z"). Ignimbrite deposition at elevated temperatures is advocated by its columnar jointing, eutaxitic texture, gas escape structures and glassy zones of intense welding. The typical mineral assemblage of all Polychnitos ignimbrite units consists of plagioclase, Kfeldspar and biotite. It displays phenocryst microtextures indicative of magma mixing. Magma mixing is corroborated of glasses of two discrete compositions. Lithic clast measurements indicate a northeasterly trending fissure vent passing from the northeastern corner of the Kalloni Gulf.

The formation and genesis of the rhyolite series of the Upper Chegem Highlands (the North Caucasus)

2020 ◽  
pp. 3-12
Author(s):  
N. V. Koronovsky ◽  
M. S. Myshenkova
Keyword(s):  
Main Part ◽  
Volcanic Rocks ◽  
Lava Flows ◽  
New Materials ◽  
North Caucasus ◽  
Columnar Jointing ◽  
Limited Volume ◽  
Late Pliocene ◽  
The North ◽  
Supercritical Water Fluid

On the basis of new materials this article deals with the structure and origin of a huge (up to 2 km) thick massif of acidic volcanic rocks located in a volcanic-tectonic depression in the Upper Chegem River in the North Caucasus. Discussion on the lava’s, rather than pyroclastic, origin of the main part of the rock mass as a result of repeated outpourings of lava flows, which formed the series of acidic volcanic rocks without interruptions with perfectly pronounced columnar jointing in a limited volume of a deep volcanic-tectonic depression, which was forming simultaneously with eruptions in the Late Pliocene. Volcanic rocks formed as a result of boiling silicate meltas the exit from the vent, which could be due to the nature of the phase transition of the supercritical water fluid.

Metasomatism in the Whin Sill of the North of England. Part II: Hydrothermal Alteration by Juvenile Solutions

1929 ◽  
Vol 66 (5) ◽  
pp. 221-238 ◽  
Author(s):  
L. R. Wager
Keyword(s):  
Thin Layer ◽  
Hydrothermal Alteration ◽  
Outer Surface ◽  
Large Scale ◽  
General Character ◽  
Small Scale ◽  
Hydrothermal Solutions ◽  
Vein Quartz ◽  
Columnar Jointing ◽  
The North

In Teesdale and Weardale, at all exposures that have been examined, the Whin Sill is cut by a system of approximately vertical, sweeping, joint planes. These are distinct in general character from, and are on a larger scale than, the columnar jointing which is conspicuous in all vertical scars of Whin Sill. The pattern of the larger scale jointing on a horizontal surface varies with the depth within the sill; Fig. 1 shows diagrammatically the appearance at a depth of about 10 feet below the top of the sill; the inset Fig. 2, of the upper surface of the sill, shows how the joints have a more irregular course in the more rapidly cooled part of the dolerite. The joints do not usually pass from the dolerite into the adjacent sediment and Fig. 2 also shows a thin layer of baked sediment, attached to the outer surface of the sill, which the joint does not penetrate. The large scale jointing is often displaced by the small scale columnar jointing in a way that proves the large scale jointing to be the earlier. For the purposes of this paper, the early, large scale, joints will be referred to simply as the early joints. The walls of the early joints, for a distance of an inch or so, have been altered by hydrothermal solutions, to a rock which, although varying in composition with the distance from the joint, consists essentially of chlorite, quartz, and carbonate. The joint walls are usually about a quarter of an inch apart, and the space between them is filled with calcite and quartz. The calcite is present in greater abundance than the quartz which occurs in well shaped crystals of vein-quartz habit.

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