ORGANIC PETROGRAPHY OF CARBONACEOUS SHALES FROM THE LOWER DEVONIAN CAMPBELLTON AND VAL D’AMOUR FORMATIONS, NEW BRUNSWICK, CANADA
All of the samples, except for the two thermally-altered samples, were high in vitrinite content (average 80.7 %, mineral matter free basis). Telovitrinite was the dominant vitrinite maceral subgroup, relative to detrovitrinite and gelovitrinite, in all of the samples (average TV/DV + GV ratio, 16.7:1), suggesting that either, 1) conditions within the paleomire were conducive to the overall preservation of organic matter (i.e., anoxic and acidic), resulting in high percentages of telovitrinite; or 2) the telovitrinite represents certain plant tissues that were highly resistant to decay. Liptinite macerals were moderate in abundance (average 18.7 % mineral matter free basis), and occurred primarily as sporinite. In two samples, cutinite was especially abundant. In these samples the cuticles, which were quite thick (commonly 20 to 30 microns), were separated by bands of telovitrinite that were arranged repetitively. In addition, the cuticles typically occurred as couplets, or were double-walled. Inertinite macerals were exceptionally rare (average 0.6 %, mineral matter free basis), which indicates either a paucity of wildfire during peat accumulation, or is a further reflection of acidic, anoxic conditions within the paleomire that not only promoted the formation of vitrinite, but also inhibited the formation of inertinite through degradational pathways.