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02520nab a2200217 4500 |
| 003 - CONTROL NUMBER IDENTIFIER |
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| control field |
GSMBLIc |
| 008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION |
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210429b ||||| |||| 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 |
Martí, J. |
| 9 (RLIN) |
11135 |
| 245 ## - TITLE STATEMENT |
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| Title |
Stratigraphy, structure and geochronology of the Las Cañadas caldera (Tenerife, Canary Islands) |
| 300 ## - PHYSICAL DESCRIPTION |
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| Extent |
715-727pp. |
| Other physical details |
Illustration |
| 520 ## - SUMMARY, ETC. |
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| Summary, etc. |
After a long period of subaerial fissure-fed extrusions of basaltic magmas (∼ 12 to > 3 Ma) volcanic activity was then concentrated in the central part of Tenerife. Phonolitic magma chambers formed and a central volcanic complex was constructed (the Las Canadas edifice). The formation of a large depression (the Las Canadas caldera) truncated the top of the edifice. The active twin strato-cones Teide—Pico Viejo are sited in this depression. The history of the Las Canadas caldera and edifice are established from stratigraphy, geochronology (K—Ar dates) and volcanological studies. Two different groups are recognized, separated by a major unconformity. The Lower Group is dated at 2 to 3 Ma and includes the products of several volcanic centres, which together represent several cycles. The Upper Group ranges from 1.56 to 0.17 Ma and includes three different formations representing three long-term (∼ 100 to 300 Ka) volcanic cycles. The periods of dormancy between each formation were of ∼ 120 to 250 Ka duration. The Las Canadas caldera is a multicyclic caldera which formed over the period 1.18–0.17 Ma. Each cycle of activity represented by a formation culminated in caldera collapse which affected different sectors of the Las Canadas edifice. Geological observation and geochronology support an origin by collapse into a magma chamber. The minimum volume of pyroclastic ejecta is substantially greater than the present caldera depression volume (45 km3), but approaches the inferred volume of the original caldera depression (> 140 km3). After the formation of the caldera, sector collapses could also occur at the northern flank of the volcano causing the disappearance of the northern side of the caldera wall. |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM |
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| Topical term or geographic name entry element |
Geochronology - Canary island |
| 9 (RLIN) |
11136 |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name entry element |
Structural geology |
| 9 (RLIN) |
1235 |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name entry element |
Stratigraphic geology |
| 9 (RLIN) |
1312 |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM |
|---|
| Topical term or geographic name entry element |
Volcanic complex - Las canadas caldera |
| 9 (RLIN) |
11137 |
| 700 ## - ADDED ENTRY--PERSONAL NAME |
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| Personal name |
Mitjavila, J. |
| 9 (RLIN) |
11138 |
| 700 ## - ADDED ENTRY--PERSONAL NAME |
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| Personal name |
Araña, V. |
| 9 (RLIN) |
8648 |
| 773 0# - HOST ITEM ENTRY |
|---|
| Host Biblionumber |
1798 |
| Host Itemnumber |
2020 |
| Place, publisher, and date of publication |
London Cambridge University Press 1994 |
| Other item identifier |
002516 |
| Title |
Geological magazine : Vol. 131 Iss. 1-6 Year. 1994 |
| International Standard Serial Number |
00167568 |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) |
|---|
| Source of classification or shelving scheme |
|
| Call number suffix |
{082b} |
| Koha item type |
Article |
