Analysis of the Major Gravity and Magnetic Anomalies Centred About Bathgate, Central Scotland

Hossain, Mia Mohammed Amzad (1976) Analysis of the Major Gravity and Magnetic Anomalies Centred About Bathgate, Central Scotland. MSc(R) thesis, University of Glasgow.

Abstract

A Bouguer anomaly map and an aeromagnetic map (Map 1 and 5) are presented for the central part of the Midland Valley of Scotland as a basis for a combined interpretation of a prominent anomaly centred near Bathgate. The gravity data are compiled from surveys carried out by I. G. S., Cotton, Qureshi, and Bullerwell and Phemister. The aeromagnetic map is part of the Great Britain and Northern Ireland, sheet 11 (scale 1:250,000) published by I. G. S. On the basis of qualitative analysis and geological argument, two limiting case models for the main anomaly are proposed for qualitative investigation. Model 1 consists of Carboniferous lavas in continuity with an intrusion of identical geophysical properties as the magnetic source. Model 2, however, attributes the whole magnetic anomaly, after some smoothing by upward continuation, to a deep intrusion. The Bouguer anomaly Map is corrected for the effect of known basins of Carboniferous sediments above the lavas filling the basins with material of Lower Old Red Sandstone density. The principal remaining components of the gravity field are considered by combining the pseudogravity anomalies, calculated from magnetic anomalies and scaled to +10 mgal for two density contrasts (+0.11 g/cm3 for shallow model and +0.45 g/cm for deeper model), with the regional gravity anomaly, projected from Western Midland Valley of Scotland. This is done after adjusting for a base level shift of 15 mgal which may arise from a NE regional gradient and/or a component of the gravity effect of the Lower Old Red Sandstone basin. The density contrasts which must be used for Model 1 and 2 suggest that the rocks are basic if the model is shallow and ultra-basic if the source is deeper.

• Item Type: Thesis (MSc(R))
• Qualification Level: Masters
• Keywords: Geophysics
• Date of Award: 1976
• Depositing User: Enlighten Team
• Unique ID: glathesis:1976-78734
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 30 Jan 2020 14:57
• Last Modified: 30 Jan 2020 14:57
• URI: https://theses.gla.ac.uk/id/eprint/78734