| 000 -LEADER |
|---|
| fixed length control field |
02230nab a2200205 4500 |
| 003 - CONTROL NUMBER IDENTIFIER |
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| control field |
GSMBLIc |
| 008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION |
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| fixed length control field |
210420b ||||| |||| 00| 0 eng d |
| 041 ## - LANGUAGE CODE |
|---|
| Language code of text/sound track or separate title |
Einglish Language |
| 100 ## - MAIN ENTRY--PERSONAL NAME |
|---|
| Personal name |
Sajeev, K. |
| 9 (RLIN) |
10491 |
| 245 ## - TITLE STATEMENT |
|---|
| Title |
An unusual high-Mg garnet–spinel orthopyroxenite from southern India: evidence for ultrahigh-temperature metamorphism at high-pressure conditions |
| 300 ## - PHYSICAL DESCRIPTION |
|---|
| Extent |
923 - 932 pp. |
| Other physical details |
Illustration |
| 520 ## - SUMMARY, ETC. |
|---|
| Summary, etc. |
We report here a garnet–spinel orthopyroxenite in close association with an ultrahigh-temperature (UHT) granulite from the central part of the Madurai Granulite Block in southern India. The garnet–spinel orthopyroxenite is almost entirely composed of orthopyroxene, spinel and rare garnet in a granular texture. Spinels in the rock are characterized by high Mg (XMg = 0.69–0.71) with low Cr and Fe3+, consistent with compositions reported from spinels occurring within xenoliths in kimberlites and high pressure–temperature (P–T) Alpine complexes. The orthopyroxenes have high Al content (Al2O3 up to 4.85 wt%), typical of equilibration under high P–T conditions. The P–T estimates derived for the garnet–spinel orthopyroxenite indicate temperatures of around 1000°C and pressures exceeding 17 kbar. The data indicate that UHT metamorphism in this locality traversed from above 17 kbar to 11 kbar prior to the final stage of isothermal decompression. Our study reports the highest pressures obtained by far, for extreme crustal metamorphism in southern India and elsewhere in Gondwana. The multi-stage decompression observed in the UHT rocks associated with the high P–T garnet–spinel orthopyroxenite could be correlated to extension of the crust and possibly of the lithospheric mantle and/or its delamination, with the asthenospheric mantle as the ultimate heat source, during the final stage of amalgamation of the Gondwana supercontinent. |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name entry element |
Garnet-spinel orthopyroxenite |
| 9 (RLIN) |
10492 |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name entry element |
UHT granulite |
| 9 (RLIN) |
10493 |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name entry element |
P-T evolution |
| 9 (RLIN) |
10494 |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name entry element |
Southern India |
| 9 (RLIN) |
10495 |
| 700 ## - ADDED ENTRY--PERSONAL NAME |
|---|
| Personal name |
Santhosh, M. |
| 9 (RLIN) |
10496 |
| 773 0# - HOST ITEM ENTRY |
|---|
| Host Biblionumber |
1899 |
| Host Itemnumber |
2187 |
| Place, publisher, and date of publication |
London Cambridge University Press 2006 |
| Other item identifier |
002538 |
| Title |
Geological magazine : Vol. 143 Iss. 1-6 Year. 2006 |
| International Standard Serial Number |
00167568 |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) |
|---|
| Source of classification or shelving scheme |
|
| Call number suffix |
{082b} |
| Koha item type |
Article |
