scholarly journals Emplacement of Amba Dongar carbonatite-alkaline complex at Cretaceous/Tertiary boundary: Evidence from40Ar-39Ar chronology

2000 ◽  
Vol 109 (1) ◽  
pp. 39-47 ◽  
Author(s):  
Jyotiranjan S. Ray ◽  
Kanchan Pande ◽  
T. R. Venkatesan
Keyword(s):  
Alkaline Complex ◽  
Amba Dongar

Low-Th pyrochlore in carbonatite from the Amba Dongar carbonatite-alkaline complex, Gujarat, India

1997 ◽  
Vol 1997 (1) ◽  
pp. 34-48 ◽  
Author(s):  
Indraneel Ghose ◽  
Michel Fialin ◽  
Jean-Robert Kienast ◽  
Srinivas G. Viladkar
Keyword(s):  
Alkaline Complex ◽  
Amba Dongar

Composition and U—Pb ages of apatite in the Amba Dongar carbonatite–alkaline complex, India

2018 ◽  
Vol 54 (6) ◽  
pp. 3438-3454 ◽  
Author(s):  
Benjamin R. Fosu ◽  
Prosenjit Ghosh ◽  
David M. Chew ◽  
Shrinivas G. Viladkar
Keyword(s):  
Alkaline Complex ◽  
Amba Dongar

A review of the composition and evolution of hydrocarbon gases during solidification of the Ilímaussaq alkaline complex, South Greenland

2001 ◽  
pp. 159-166 ◽  
Author(s):  
Jens Konnerup-Madsen
Keyword(s):  
Nepheline Syenite ◽  
Subsequent Development ◽  
High Water ◽  
Vapour Phase ◽  
Low Carbon ◽  
Low Oxygen ◽  
Alkaline Complex ◽  
Hydrocarbon Gases ◽  
Wide Range ◽  
Water Contents

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Konnerup-Madsen, J. (2001). A review of the composition and evolution of hydrocarbon gases during solidification of the Ilímaussaq alkaline complex, South Greenland. Geology of Greenland Survey Bulletin, 190, 159-166. https://doi.org/10.34194/ggub.v190.5187 _______________ Fluid inclusions in minerals from agpaitic nepheline syenites and hydrothermal veins in the Ilímaussaq complex and in similar agpaitic complexes on the Kola Peninsula, Russia, are dominated by hydrocarbon gases (predominantly methane) and hydrogen. Such volatile compositions differ considerably from those of most other igneous rocks and their formation and entrapment in minerals reflects low oxygen fugacities and a wide range of crystallisation temperatures extending to a low-temperature solidus. Their composition reflects initial low carbon contents and high water contents of the magma resulting in the exsolution of a waterrich CO2–H2O dominated vapour phase. Fractionation of chlorides into the vapour phase results in high salinities and the subsequent development of a heterogeneous vapour phase with a highly saline aqueous-rich fraction and a methane-dominated fraction, with preferential entrapment of the latter, possibly due to different wetting characteristics. The light stable isotope compositions support an abiogenic origin for the hydrocarbons in agpaitic nepheline syenite complexes.

Natrophosphate from the Ilímaussaq alkaline complex, South Greenland

2001 ◽  
pp. 139-141
Author(s):  
Ole V. Petersen ◽  
Alexander P. Khomyakov ◽  
Henning Sørensen
Keyword(s):  
Refractive Index ◽  
Kola Peninsula ◽  
Unit Cell Parameter ◽  
Cell Parameter ◽  
Water Soluble ◽  
Type Locality ◽  
Drill Core ◽  
Alkaline Complex ◽  
First Time ◽  
Alkaline Complexes

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Petersen, O. V., Khomyakov, A. P., & Henning. (2001). Natrophosphate from the Ilímaussaq alkaline complex, South Greenland. Geology of Greenland Survey Bulletin, 190, 139-141. https://doi.org/10.34194/ggub.v190.5184 _______________ The rare mineral natrophosphate has been identified for the first time in the Ilímaussaq alkaline complex in a drill core from the Kvanefjeld area. It occurs sparsely in zoned veinlets with cores of natrophosphate and borders of fibrous trona. The natrophosphate is more or less smoky, transparent and unaltered. The refractive index n = 1.448 ± 0.005 is low compared to that given for the material from the type locality, Khibina alkaline complex, Kola Peninsula; the unit cell parameter a = 27.76 ± 0.05 Å is in excellent agreement with that given for the material from the type locality. The veins occur in hyper-agpaitic naujakasite lujavrite; villiaumite is an associated mineral. Only a few water-soluble minerals have so far been found in the Ilímaussaq alkaline complex compared to the wealth of such minerals in the Khibina and Lovozero alkaline complexes. This is possibly at least partly due to lack of necessary precautions during sampling.

Age and petrogenesis of the Neoproterozoic Chon-Ashu alkaline complex, and a new discovery of chalcopyrite mineralization in the eastern Kyrgyz Tien Shan

2014 ◽  
Vol 61 ◽  
pp. 175-191 ◽  
Author(s):  
Dmitry Konopelko ◽  
Georgy Biske ◽  
Reimar Seltmann ◽  
Sergey V. Petrov ◽  
Elena Lepekhina
Keyword(s):  
Tien Shan ◽  
Alkaline Complex ◽  
New Discovery

Mineralogy and geochemistry of a giant agpaitic magma reservoir: The Late Cretaceous Poços de Caldas potassic alkaline complex (SE Brazil)

Lithos ◽  
2021 ◽  
pp. 106330
Author(s):  
Vincenza Guarino ◽  
Michele Lustrino ◽  
Alberto Zanetti ◽  
Colombo C.G. Tassinari ◽  
Excelso Ruberti ◽  
...  
Keyword(s):  
Late Cretaceous ◽  
Magma Reservoir ◽  
Alkaline Complex ◽  
Se Brazil ◽  
Poços De Caldas

scholarly journals An Overview of the Carbonatites from the Indian Subcontinent

2020 ◽  
Vol 12 (1) ◽  
pp. 85-116 ◽  
Author(s):  
Kirtikumar Randive ◽  
Tushar Meshram
Keyword(s):  
Sri Lanka ◽  
Indian Subcontinent ◽  
Source Rocks ◽  
Time Range ◽  
Alkaline Complex ◽  
Comprehensive Information ◽  
Igneous Origin ◽  
Continental Rifts ◽  
Low Degrees ◽  
Orogenic Belts

AbstractCarbonatites are carbonate-rich rocks of igneous origin. They form the magmas of their own that are generated in the deep mantle by low degrees of partial melting of carbonated peridotite or eclogite source rocks. They are known to occur since the Archaean times till recent, the activity showing gradual increase from older to younger times. They are commonly associated with alkaline rocks and be genetically related with them. They often induce metasomatic alteration in the country rocks forming an aureole of fenitization around them. They are host for economically important mineral deposits including rare metals and REE. They are commonly associated with the continental rifts, but are also common in the orogenic belts; but not known to occur in the intra-plate regions. The carbonatites are known to occur all over the globe, majority of the occurrences located in Africa, Fenno-Scandinavia, Karelian-Kola, Mongolia, China, Australia, South America and India. In the Indian Subcontinent carbonatites occur in India, Pakistan, Afghanistan and Sri Lanka; but so far not known to occur in Nepal, Bhutan, Bangladesh and Myanmar. This paper takes an overview of the carbonatite occurrences in the Indian Subcontinent in the light of recent data. The localities being discussed in detail cover a considerable time range (>2400 Ma to <0.6 Ma) from India (Hogenakal, Newania, Sevathur, Sung Valley, Sarnu-Dandali and Mundwara, and Amba Dongar), Pakistan (Permian Koga and Tertiary Pehsawar Plain Alkaline Complex which includes Loe Shilman, Sillai Patti, Jambil and Jawar), Afghanistan (Khanneshin) and Sri Lanka (Eppawala). This review provide the comprehensive information about geochemical characteristics and evolution of carbonatites in Indian Subcontinent with respect to space and time.

Sign in / Sign up

Export Citation Format

Share Document