Microfacies analysis and diagenetic fabric of Lockhart Limestone exposed along Nathiagali-Murree Road, District Abbottabad, Pakistan
Keywords:
Microfacies; Lockhart Limestone; Diagenetic fabric; Depositional fabric.Abstract
The microfacies analysis and digenetic fabric of the Lockhart Limestone (Paleocene age) are studied at two different geological field sections. The study is based on field and laboratory observations. The formation is predominantly comprised of medium to thick bedded, nodular and occasionally brecciated, highly fossiliferous, limestone with thin interbeds of clay/marl.
Four carbonate microfacies are, 1) Algal Foraminiferal Packstone microfacies of inner shelf, 2) Mixed Bioclastic Wacke-Packstone microfacies of middle shelf, 3) Benthic Foraminiferal WackePackstone microfacies of middle-outer shelf and 4) Planktic-Benthic Foraminiferal Wacke-Packstone microfacies of outer shelf. While the diagenetic history is characterized by several diagenetic features of aragonite to calcite transformation, compaction, pressure dissolution (microstylolites), calcite-filled microfractures, development of microspar, micritization and nodularity.
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