A thick succession of sedimentary rocks, comprising mainly Paleozoic shallow-marine and fluvial deposits, and Mesozoic and Paleogene marine carbonates, with subordinate clastics and evaporites, occurs in Jordan. These are preserved in several basins, including: Late Paleozoic inverted basins with thick, Infra-Cambrian to Silurian successions in the south, east and NE; and younger, Late Cretaceous and/or Tertiary basins in the centre and west, in which Mesozoic marine shelf sediments and/or thick, rift-related Neogene sediments are well-developed. Two regional, organic-rich source-rock levels occur. They comprise Upper Ordovician/Lower Silurian shales in the SE half of the country, and Upper Cretaceous, bituminous chalky marls in the western/central sectors; the former range from immature in the SW to locally over-mature in the NE, whereas the latter are mainly immature, except where deeply buried, as in the Jordan Valley/Dead Sea rift and part of the Azraq rift. Subordinate source-rock levels occur in the Triassic and Middle Cretaceous. Numerous hydrocarbon indications, including seeps and floating asphalt blocks, occur in the Dead Sea area and have been correlated with the Upper Cretaceous source rocks. In spite of these positive indications, only 13 exploration wells have been drilled since drilling first began in the mid-1950s. The Natural Resources Authority (NRA) has established modest oil and gas production in two fields, mainly through the drilling of well clusters in encouraging areas. Hydrocarbons potential, however, remains good, with play concepts related to the major source levels. Detailed local and regional analytical studies, together with extensive and sophisticated seismic acquisition and processing/reprocessing, are required, however, prior to further drilling, with clear and separate strategies for each of the plays.