Title of Thesis
GEOCHRONOLOGICAL STUDIES OF THE CARBONATITE COMPLEXES WITHIN THE PESHAWAR PLAIN ALKALINE IGNEOUS PROVINCE USING FISSION-TRACK DATING TECHNIQUE
Author(s)
Nimat Ullah
Institute/University/Department Details
National Centre of Excellence in Geology/ University of Peshawar,
Session
2006
Subject
Geology
Number of Pages
221
Keywords (Extracted from title, table of contents and abstract of thesis)
carbonatite, peshawar, alkaline igneous, fission-track dating technique, peshawar plain alkaline igneous province, paip, loe-shilman, sillai patti, khungi, jambil, koga, tarbela, petrogenesis, fission tracks, collisional tectonics
Abstract
The earlier workers have considered the carbonatite occurrences of northern Pakistan as the members of the Peshawar Plain Alkaline Igneous Province (PAIP), which is over a 150 km long and discontinuous belt of carbonatites and alkaline igneous rocks, extending from Pak-Afghan border in the west up to Tarbela area in the east. Within the PAIP, Carbonatite occurrences are found at the localities of Loe-Shilman in Khyber Agency, Sillai Patti in Malakand Agency, Khungi in Mardan, Jambil in Lower Swat, Koga in Buner, Tarbela near Topi along the west bank of River Indus and a seventh location recently discovered in the Jawar area about 4 km to the north west of Sillai Patti in Bajaur Agency.
No geochronological studies have previously been conducted on the Jawar and Jambil carbonatites of the region, while, available geochronological data on the other carbonatite occurrences of the region is very scarce. Except the Sillai Patti carbonatite occurrence, none of the carbonatites of the region has been studied with the fission-track dating technique before this study.
All the earlier workers have accepted the carbonatites of the Koga area to be of Carboniferous age. However, there has been a dispute over the emplacement time (s) of the Loe-Shilman and Sillai Patti carbonatite complexes. One group of geologists considers all the carbonatites and their associated alkaline rocks of the PAIP to have been emplaced during a single alkaline and carbonatitic magmatic episode of Permo-Carboniferous age in the region. However, a second group of geologists considers all the carbonatites and associated alkaline rocks of the PAIP were emplaced at least in two alkaline and Carbonatitic magmatic episodes, during the (i) Carboniferous and (ii) Tertiary (Oligocene), respectively. According to the second group of geologists, emplacement of the Koga carbonatite took place during the Permo-Carboniferous alkaline magmatism, while emplacement of the Loe-Shilman and Sillai Patti carbonatite carbonatite complexes took place during the Tertiary alkaline and carbonatitic magmatic episode.
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