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Detailed rock magnetic, facies and textural analyses were carried out across the San Bartolo lava flow (Stromboli) to understand the flow dynamics of lava channel-fed 'a'a entering the water. Having been emplaced 3 ka, San Bartolo is the most recent lava flow field to have been emplaced beyond the Sciara del Fuoco, and underlies the inhabited area on the north-eastern side of the island. One of the remarkable features of the San Bartolo lava flow is the formation of several lobes due to the interaction with seawater. Field analysis shows three facies: 1. Stalling of flow fronts at the coastal interaction to form a littoral barrier to further flow, 2. Ramping of subsequently emplaced units behind this barrier, and creation of a degassed ponded volume, 3. Creation of tubes through the barrier to feed a seaward bench of pahoehoe. Around 12 lobes were identified. All the lobes show similar facies, but each lobe provides a case-type example of the emplacement history and the associated structures. For example, lobe 1 exhibits tube formation associated through the flow front barrier; while lobe 12 shows the formation of inflated pahoehoe lava. Preliminary AMS results show well-confined flow fabrics with a one-to-one relationship to field structures. The samples collected from ramped flow have vertical flow fabrics, while those from tube structures and inflated pahoehoe have horizontal fabrics. Preliminary palaeomagnetic data have characteristic remanent magnetisation (ChRM) directions for all the sampled lobes, with their a95 overlapping, suggesting rapid emplacement. In addition, the average ChRM direction falls in the geocentric axial dipole (GAD) field for Stromboli.

Dykes and Sills are the primary subvolcanic bodies that transport magma from the deep-seated magma reservoir or from the shallow magma chamber. The mechanism of magma transport and emplacement in dyke swarms is significant, as their passage from magma chamber through the crust to the surface or near-surface settings can provide valuable information on source and how magma has interacted with crustal rocks.Here, we are presenting the preliminary findings obtained from the Anisotropy of Magnetic Susceptibility (AMS) and Palaeomagnetic analysis to study the magma transport mechanism and emplacement history of Mount Calanna dyke swarms of Mount Etna. In order to find their magnetic fabrics, we systematically sampled 45 oriented hand samples from 11 dykes where at least two samples were collected from both dyke boundary and centre. Using the obtained AMS fabrics, we attempt to find the emplacement mechanisms of dykes in Mount Calanna and its relationship to Mount Etna.AMS technique provides valuable information regarding the dyke emplacement such as whether the Mount Calanna dykes are feeders, and whether they are the result of polycentric, vertical or lateral magma flow. Based on the intersection of the AMS axis with the dyke plane, we were able to identify two classes, one where the dyke plane intersects with the maximum principal susceptibility axes (Kmax) and the other where the dyke plane intersects with the minimum principal susceptibility axes (Kmin). Nevertheless, the variation in the shape parameter from centre to boundary shows the effect of shear, magma viscosity and the host rock strength on magma emplacement. The Paleomagnetic techniques enable us to unravel the relative timing of the injection of the dykes and the possible tectonic control on their emplacement.

Coal porosity and permeability are key petrophysical parameters, pivotal in facilitating coalbed methane extraction and CO2 sequestration. Distribution of coal fractures, their association with coal stratigraphy, and their depth of occurrence primarily control coal porosity and permeability. The primary coal fracture networks, made of cleats, are the fundamental pathways for fluid flow through coal seams as matrix porosity and permeability are negligible. This paper documents the distribution of cleats and interrelationships amongst their attributes (aperture, spacing) as a function of depth and their role in controlling the porosity-permeability distribution of the Gondwana coals (Raniganj Formation) from India. The analytically computed effective permeability (based on effective aperture) estimations using the measured cleat parameters are more than two orders of magnitude higher than previously reported permeability values derived from geophysical log analysis, laboratory measurements and field tests. Such gaps between analytical results and measured data are also reported from multiple coal-bearing basins around the world. We, therefore, carry out an uncertainty analysis of measured aperture and used reported limits of cleat compressibility to estimate the range of possible permeabilities. We infer that the analytical solution combining the lower bounds of aperture distribution and cleat compressibility can be used as the closest approximation of effective permeability at pre-drill exploration stage of a coalbed methane project.