Details of Award
NERC Reference : NE/E019021/1
On the trail of flood-basalt vent systems from the western Deccan Volcanic Province, India
Grant Award
- Principal Investigator:
- Dr S Blake, The Open University, Environment, Earth & Ecosystems
- Grant held at:
- The Open University, Environment, Earth & Ecosystems
- Science Area:
- Earth
- Overall Classification:
- Earth
- ENRIs:
- Global Change
- Science Topics:
- Volcanic Processes
- Palaeoenvironments
- Abstract:
- The Deccan Volcanic Province of western India (formed around 65-66 million years ago) is one of the largest continental flood basalt provinces in the world. Such provinces represent the eruption of phenomenal volumes of basaltic lavas, which spread over the surface to fill and occupy hundreds of thousands of square kilometres. Understanding how these provinces were formed is of great significance to several topics, including the origins of voluminous volcanism (so-called large igneous provinces - LIPs) on Earth, the storage of magmas beneath the Earth's surface, and mass extinctions. One notable feature of flood basalt provinces is that the vents for the lavas are very poorly understood, as very few examples have been described, and these are all from the same province, the 'small', young (15 million-years-old) Columbia River basalts, USA. In the western Deccan province, such flood basalt lava flows reach exposed thicknesses of well over a kilometre and provide an excellent opportunity to understand many of the outstanding questions pertaining to flood basalt volcanism, including locating the vents and their related volcanic deposits. Our study will investigate the nature of flood basalt vent sites in a certain area of the Deccan province where some examples are already known to exist, and in which there are a number of feeder dykes (high-level, sheet-like intrusions of magma into Earth's upper crust). The dykes are testimony that magma rose towards the surface in this region, and lava vents are related to these dykes. The flows fed by these vents may be some of the biggest volcanic eruptive units on Earth, but this remains to be tested. By combining the expertise of an experienced investigator who has worked on one of the vent systems in the Columbia River flood basalt province with a relatively new Indian researcher with detailed knowledge of the vital part of the Deccan province, we hope to build up a convincing picture of the source region of some of these great lava flows and of the types of volcanoes that may have been built there. Thus, the work proposed will also bear on an old, yet incompletely resolved, issue in geology, that of the nature of the source regions of the flood basalt lava flows. This debate goes back to the 1880s, the main point being whether flood basalt lavas in LIPs were fed from central volcanoes or from widely dispersed fissures. Some LIPs, for example, the CRB province, appear to be entirely fissure-fed, but the Deccan may be different? We have very little direct knowledge about the actual eruptive vent processes in continental flood basalt volcanism because the deposits are so elusive, and this proposed research will try to provide that evidence and also answer some major questions, such as the nature and size of flood basalt eruptions; were they small and frequent or large and infrequent in this region of the Deccan province? The project depends on detailed mapping and collection of field data, without which issues such as understanding the precise eruption style of flood basalts will remain unsolved. Deccan volcanism coincides in time with one of the largest mass extinctions that this planet has ever witnessed, in which the reign of the dinosaurs was ended. But did the volcanism have anything to do with the extinction, or was the extinction largely the result of a meteoritic impact? It has only recently begun to be recognised that flood basalt eruptions feature fire-fountain activity at the vents. It seems unavoidable that sufficiently large fire-fountains must be topped by vigorously rising ash plumes, capable of transporting noxious gases high into the atmosphere. Around the vents, distinctive volcanic deposits develop. Making detailed observations of volcanic vent deposits preserved in this one part of the Deccan lava field will be a major step towards our understanding of the potential for this volcanism to cause regional or global environmental change.
- NERC Reference:
- NE/E019021/1
- Grant Stage:
- Completed
- Scheme:
- Standard Grant (FEC)
- Grant Status:
- Closed
- Programme:
- Standard Grant
This grant award has a total value of £265,952
FDAB - Financial Details (Award breakdown by headings)
| DI - Other Costs | Indirect - Indirect Costs | DA - Investigators | DI - Staff | DA - Estate Costs | DI - T&S | DA - Other Directly Allocated |
|---|---|---|---|---|---|---|
| £12,839 | £98,288 | £21,252 | £81,610 | £31,398 | £5,229 | £15,335 |
If you need further help, please read the user guide.