The so far unstudied Oligocene and Miocene organic matter–rich deposits of the Cunapo and Nariva Formation of northern and central Trinidad, western tropical Atlantic Ocean have been investigated using organic geochemical and organic petrological techniques to assess the thermal maturity and paleoenvironmental conditions during peat accumulation. Twenty samples were collected along various sections within the Cunapo and Nariva formations. Evaluation based on organic petrological analyses and Rock-Eval pyrolysis reveals that the coals and carbonaceous shales are thermally immature in the lignite and subbituminous rank for Cunapo Formation and mature in the subbituminous to high-volatile bituminous rank for Nariva Formation. The respective maturities correspond to high volatile matter contents.

Petrographically, the Cunapo Formation coals are dominated by huminite with minor amounts of inertinite and liptinite, and the Nariva Formation coals contain high amounts of vitrinite, with moderate to low liptinite and low inertinite contents. The detailed petrographic data for Cunapo and Nariva coals indicate predominantely limnic conditions and a herbaceous origin of organic matter. Further conclusions are deduced from petrographic ratios such as gelification-, tissue preservation-, vegetation- and groundwater_AC indices, ash- and sulfur contents, iso- and n-alkane distribution, and 17α(H)-homohopane ratio. In summary, the data supports that both the Cunapo and Nariva coals formed in a tropical peat environment, partly influenced by very high microbial activity and ± in case of Nariva coals - partly grading into ombrogenic mires. The Cunapo coals were influenced by the development of the Orinoco River system during the Miocene and exposure to marine water during transgressive phases in a tidal, coastal environment.

使用有机地球化学和有机岩石学技术对特立尼达北部和中部、热带大西洋西部的渐新世和中新世富含有机质的沉积物进行了研究，以评估泥炭堆积过程中的热成熟度和古环境条件。沿着库纳波和纳里瓦地层的不同剖面采集了 20 个样本。基于有机岩石学分析和岩石评估热解的评估表明，Cunapo 组的褐煤和次烟煤级别的煤和碳质页岩是热未成熟的，而 Nariva 组的次烟煤到高挥发分烟煤级别的煤和碳质页岩是热成熟的。相应的成熟度对应于高挥发物含量。

从岩相上看，Cunapo 组煤以腐石质为主，含有少量惰质组和脂质组，而 Nariva 组煤含有大量镜质组，其中脂质组含量为中至低，惰质组含量较低。库纳波煤和纳里瓦煤的详细岩相数据表明，主要是湖沼条件和有机质的草本来源。进一步的结论是从岩石学比率中得出的，例如凝胶化指数、组织保存指数、植被指数和地下水_AC指数、灰分和硫含量、异烷烃和正烷烃分布以及17α(H)-高藿烷比率。总之，数据支持库纳波煤和纳里瓦煤都是在热带泥炭环境中形成的，部分受到非常高的微生物活动的影响，并且±纳里瓦煤的情况 - 部分分级为暗淡泥炭。库纳波煤炭受到中新世奥里诺科河系统发展以及潮汐沿海环境海侵阶段海水暴露的影响。