We present a comprehensive facies scheme for west-central Jordan platform deposits of upper Albian to Turonian age, discuss Cenomanian and Turonian carbonate cycles, and reconstruct the paleogeographic evolution of the platform. Comparisons with adjacent shelf areas (Israel, Sinai) emphasize local characteristics as well as the regional platform development. Platform deposits are subdivided into fifteen microfacies types that define eight environments of deposition of three facies belts. Main facies differences between Cenomanian and Turonian platforms are: rudist-bearing packstones that characterise the higher-energy shallow subtidal (transition zone) during the Cenomanian, and fossiliferous (commonly with diverse foraminifer assemblages) wackestones and packstones of an open shallow subtidal environment. On Turonian platforms high-energy environments are predominantly characterised by oolithic or bioclastic grainstones and packstones, whereas peritidal facies are indicated by dolomitic wackestones with thin, wavy (cryptmicrobial) lamination. Rhythmic facies changes define peritidal or subtidal shallowing-up carbonate cycles in several Cenomanian and Turonian platform intervals. Cyclicities are also analysed on the base of accommodation plots (Fischer Plots). High-frequency accommodation changes within lower Cenomanian cyclic bedded limestones of the central and southern area exhibit two major 'cyclic sets' (set I and II) each containing regionally comparable peaks. Accommodation patterns within cyclic set II coincide with the sequence boundary zone of CeJo1. The lateral and vertical facies distributions on the inner shelf allow the reconstruction of paleogeographic conditions during five time intervals (Interval A to E). An increased subsidence is assumed for the central study area, locally (area of Wadi Al Karak) persisting from middle Cenomanian to middle Turonian times. In contrast, inversion and the development of a paleo-high have been postulated for an adjacent area (Wadi Mujib) during late Cenomanian to early Turonian times, while small-scale sub-basins with an occasionally dysoxic facies developed northwards and further south during this time interval. A connection between these structural elements in Jordan with basins and uplift areas in Egypt and Israel during equivalent time intervals is assumed. This emphasises the mostly concordant development of that Levant Platform segment.

We studied upper Albian to Turonian shallowmarine shelf deposits (Ajlun Group) of west central Jordan along a NNE-SSW running transect. The carbonate-dominated succession includes few siliciclastic intercalations, claystones and shales, and can be subdivided into five formations. The Naur, Fuheis and Hummar Formations of upper Albian to upper Cenomanian age represent shallow subtidal to supratidal platform environments. The uppermost Cenomanian to middle Turonian Shueib Formation includes deeper water deposits of the inner/mid-shelf and locally TOC-rich black shales. Shallow-marine platform environments once again dominate the Wadi As Sir Formation (middle-upper Turonian). A new multibiostratigraphic framework is based on ammonites (mainly of the middle Cenomanian rhotomagense Zone to the middle Turonian woollgari Zone) and calcareous nannofossils (biozones CC 9-CC 11), supplemented by benthic and planktonic foraminifers and ostracods. It forms the base of a sequence stratigraphic subdivision, containing eight sedimentary sequences (S1-S8), which are separated by four Cenomanian sequence boundaries (CeJo1-CeJo4) and three Turonian sequence boundaries (TuJo1-TuJo3). This scheme allows the correlation of the platform succession from distal to proximal shelf areas in contrast to previous correlations using lithologic units. Furthermore, comparisons between the platform successions and sequence patterns of west central Jordan and those from neighbouring areas allow to differentiate local, regional, and global controlling factors of platform development within the study area.

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Acquisition of whole core data allows detailed rock typing profiles to be defined which are required to assign flow properties for dynamic reservoir simulation. Conventional core analysis provides lab measurements of porosity, permeability and pore size distribution sampled at plug locations with a limited sampling increment. Whole core CT scanning allows for a more continuous detailed evaluation of the cored intervals which allow the precise boundaries of specific Rock Types to be defined. This paper illustrates how novel techniques of data analysis and graphic displays of both whole core CT data and wireline NMR have been used to aid the definition of Rock Types and Flow Units. Rock Types have been categorized based on flow properties using plug porosity, permeability and MICP data. Processing of whole core CT data and wireline NMR has been performed in order to assess the heterogeneity measured by both acquisition methods. For the CT data set Heterogeneity Logs have been generated, these logs display the variation of CT density of the whole core. The logs have enabled very fine scale definition of lithotypes. In a similar manner the NMR logs were also analyzed and processed to extract specific statistical moments such as modes, magnitudes and skewness. Both sets of data were then integrated with core analysis data and thin sections. Excellent correlation between core plug, CT Heterogeneity Logs, NMR and thin section pore size distribution was observed and this has enabled the definition of Rock Types from the fine scale CT Heterogeneity Logs and Flow Units from the coarser scale wireline NMR data. The techniques described are applied to data from a heterogeneous evaporitic carbonate reservoir, where pore size distribution has a major effect on permeability and productivity. Eight Rock Types have been categorized from core analysis and these have been propagated from plug locations using the CT Heterogeneity Logs to assist manual interpretation. Neural Network and geostatistics were applied to propagate to uncored wells and throughout the geocellular model. The acquisition of core data and subsequent Heterogeneity Logs from whole core CT has proved very beneficial in the understanding of the wireline NMR tool response and has given confidence in the predictive ability of NMR to distinguish reservoir Flow Units in uncored intervals or wells.