The lacustrine Burdiehouse Limestone Formation—a key to the deposition of the Dinantian Oil Shales of Scotland

Abstract

Summary Oil shales, and the less common limestones associated with them, represent freshwater lacustrine phases within the Dinantian Oil Shale Group at the eastern end of the Midland Valley of Scotland. The understanding of the areally extensive Burdiehouse Limestone Formation is fundamental to an appreciation of the palaeolimnology of the lake in which algal oozes (consisting mainly of planktonic algae analogous to the modern form Botryococcus braunii ), later to become oil shales, accumulated. The lake, referred to as Lake Cadell, was shallow (< 100 m) with gently sloping margins. It was meromictic and formed a closed system during deposition of the limestones, draining eastwards to the sea during oil shale deposition. The climate was wet tropical ensuring ideal conditions for a prolific flora of algae and vascular plants both around and within the lake, and providing a regular freshwater input. The lacustrine phase forms part of the cyclical Oil Shale Group succession in which each sedimentary cycle can be resolved into four phases indicating long-term lake expansion and contraction.

A depositional model for spherulitic carbonates associated with alkaline, volcanic lakes

“…2B). The accumulation of planktonic and benthic microorganisms gave rise to oil-shale deposits under exorheic, meromictic, and deep (50 to 100m) conditions (Loftus and Greensmith, 1988;Parnell, 1988). The East Kirkton Limestone formed within this lake complex (FIG.…”

Carboniferous petroleum systems around the Mid North Sea High, UK

“…Coals form a significant component of the succession, which is age-equivalent of the Scremerston Formation to the south and east of the MNSH, and the organic-rich, oil-prone lacustrine West Lothian Oil-Shale Formation of the onshore Midland Valley of Scotland (Cameron 1993 a, b;Kearsey et al, 2015;Loftus andGreensmith, 1988, Parnell, 1988). Westphalian strata, age-equivalent to the Coal Measures, are recorded in well 26/08-1 and though mudstone intervals are present, coals are lacking.…”

“…Gas mature intervals may be present in the deepest parts of the basin but the volume of gas mature strata at the Cenozoic critical moment may be limited. If extensive lacustrine oil-shales exist offshore, as they do onshore in the Midland Valley of Scotland (Loftus and Greensmith, 1988;Monaghan, 2014;Parnell, 1988) then an oil-prone play could be prospective, based on current basin modelling. Seismic data quality and spacing are such that there is a risk to accurately mapping basin geometries within the structurally complex Carboniferous basin.…”

Stratigraphic and palaeoenvironmental significance of microbial carbonates in the Asbian Sandy Craig Formation of Fife

“…At times, freshwater limestones and dolostones formed, some of which contain desiccation cracks and intraclastic breccias indicating emergence. Reviews of the general environment of deposition have been given by Greensmith (1966Greensmith ( , 1968, Maddox & Andrews (1987), Loftus & Greensmith (1988), Parnell (1988), Upton (1994), Whyte (1994) and Follows & Tyson (1998). Regionally persistent marker horizons are rare, restricted to thin marine bands and the freshwater Burdiehouse Limestone (BHL).…”

“…The Bathgate Volcanic Formation is part of the Bathgate Group. Loftus & Greensmith (1988). Those workers used the term Lake Cadell to describe the environment of freshwater oil-shale deposition.…”