Abstract Only two hydrocarbon fields have been discovered in Jordan so far, despite the drilling of more than 120 petroleum wells. The Silurian-sourced and Ordovician-reservoired Risha gas field in Northeast Jordan originally had a recoverable gas reserve of around 350 billion cubic feet (bcf). Since production started in 1989, almost half has already been produced. According to Jordan’s National Petroleum Company (NPC), original gas reserves of the Risha field are up to 2–3 trillion cubic feet. The same play generated oil in the Wadi Sirhan area, where small amounts of light oil were tested in Well Wadi Sirhan-4 (WS-4). The second field in Jordan is the Hamzeh oil field in central North Jordan. However, with only modest original, recoverable reserves of 1 million barrels (MMBO), of which 0.86 MMBO has already been produced at an average rate of 40 barrels of oil per day. Current exploration in the country concentrates on Maastrichtian oil shale exploration in central Jordan, where the world’s fourth largest oil shale reserves are located. Organic richness in the Muwaqqar Chalk Marl Formation partly exceeds 20%. Besides traditional open pit mining, modern in situ oil generating techniques could be applied in Jordanian oil shale exploration. The same oil shale unit also exists underneath the Dead Sea pull-apart basin, where it is deeply buried in the oil and gas generative windows. Hydrocarbon indications occur across the Dead Sea Basin and include numerous oil and gas seeps, tar sands, heavy oil, and floating asphalt blocks in Dead Sea waters and on the shoreline. Nevertheless, exploration efforts in the Dead Sea have been disappointing so far and resulted in the discovery of just a few small commercial gas accumulations wich lie on the Israeli side of the basin, namely the Zohar, Kidod, and Haqanaim gas fields. Other frontier plays in Jordan include the Cambrian in the Jafr Rift and the Triassic-Jurassic in northern Jordan.

Abstract This review covers global uppermost Neoproterozoic–Cambrian petroleum systems using published information and the results of studies undertaken by the Geological Survey of Western Australia (GSWA) on the Neoproterozoic Officer Basin. Both production and hydrocarbon (HC) shows sourced from, and reservoired in, uppermost Neoproterozoic–Cambrian successions occur worldwide, and these provide ample incentive for continuing exploration for these older petroleum systems. However, the risks of charge volume, timing of generation–migration v. trap formation and preservation of accumulation are significantly higher than in conventional Phanerozoic petroleum systems. Therefore, the location and assessment of preserved HC accumulations in such old petroleum systems presents a significant exploration challenge. Organic-rich metamorphosed Proterozoic successions of SE Greenland, the Ukrainian Krivoy Roy Series, the Canadian Upper Huronian Series and the oil shales of the Russian Onega Basin are known as the world's oldest overmature petroleum source rocks. The oldest live oil has been recovered from the McArthur Basin of Australia ( c . 1.4 Ga; Ga is 10 9 years), followed by the Nonesuch oil of Michigan. Numerous other petroleum shows have been reported from Australia, Canada, China, India, Morocco, Mauritania, Mali, Oman, Pakistan, Venezuela and the USA. These demonstrate that generation and migration of Proterozoic petroleum has occurred worldwide. The Siberian Lena–Tunguska province, the Russian Volga–Ural region and the Middle Eastern south Oman petroleum fields exemplify the productive potential of uppermost Neoproterozoic–Cambrian successions, where petroleum generation, migration and trapping were either late in the geological history (Palaeozoic–Mesozoic, Oman) or where accumulations have been preserved beneath highly effective super-seals (Lena–Tunguska). The total resource potential of the Lena–Tunguska petroleum province is estimated to be 2000 Mbbl (million barrels) oil and 83 Tcf (trillion cubic feet) gas. The equivalent proven and probable reserves derived from Neoproterozoic–Early Cambrian source rocks and trapped in Late Neoproterozoic (Ediacaran), Palaeozoic and Mesozoic reservoirs in Oman are at least 12 bbbl (billion barrels) of oil and an undetermined volume of gas. The recovery of 12 Mcf (million cubic feet) of Precambrian gas from the Ooraminna-1 well in the Amadeus Basin in 1963, together with the occurrence of numerous HC shows within the Australian Centralian Superbasin, triggered the initial exploration for Proterozoic hydrocarbons in Australia. This included exploration in the Neoproterozoic Officer Basin, which is reviewed in this paper as a case study. Minor oil shows and numerous bitumen occurrences have been reported from the 24 petroleum exploration wells drilled in the Officer Basin to date, indicating the existence of a Neoproterozoic petroleum system. However, the potential of the Neoproterozoic petroleum system in the vast underexplored Officer Basin, with its sparse well control, remains unverified, but may be significant, as may that of many other ‘Infracambrian’ basins around the world.