Tectonic Influences on SE Asian Carbonate Systems and their Reservoir Development

Abstract

SE Asian carbonate formations have been reviewed with the aim of understanding the influence of tectonics on their development and reservoir potential through the Cenozoic. Regional tectonics, via plate movements, extensional basin formation, and uplift, was the dominant control on the location of carbonate deposits. These processes controlled the movement of shallow marine areas into the tropics, together with their emergence and disappearance. Although ; 70% of the 250 shallow marine carbonate formations in SE Asia were initiated as attached features, 90% of economic hydrocarbon discoveries are in carbonate strata developed over antecedent topography, of which more than 75% were isolated platforms. Faulted highs influenced the siting of nearly two thirds of carbonates developed over antecedent topography. Around a third of carbonate units formed in intra-and interarc areas; however, economic reservoirs are mainly in backarc and rift-margin settings (; 40% each). Carbonate edifices show evidence of syntectonic sedimentation through: (1) fault-margin collapse and resedimentation, (2) fault segmentation of platforms, (3) tilted strata and differential generation of accommodation space, and (4) modification of internal sequence character and facies distribution. The demise of many platforms, particularly those forming economic reservoirs, was influenced by tectonic subsidence, often in combination with eustatic sea-level rise and environmental perturbations. Fractures, if open or widened by dissolution, enhance reservoir quality. However, fracturing may also result in compartmentalization of reservoirs through formation of fault gouge, or fault leakage via compromised seal integrity. This study will help in reservoir prediction in complex tectonic regions as the petroleum industry focuses on further exploration and development of economically important carbonate reservoirs.

Diagenesis and fracturing of a large-scale, syntectonic carbonate platform

“…ACCEPTED MANUSCRIPT 3 The development of syntectonic carbonate platforms from a range of tectonic regimes is widely documented in the literature (Burchette, 1988;Gawthorpe et al, 1994;Dorobek, 1995;2008a;2008b;Wilson et al, 2000;Wilson and Hall, 2010), yet the diagenesis of such platforms is poorly detailed. In the active tectonic area of SE Asia at least two-thirds of the isolated carbonate platforms are documented to have formed over faulted antecedent highs with carbonate accumulation on many of these platforms coeval with local continued tectonism; i.e., many are syntectonic (Wilson and Hall, 2010).…”

“…In the active tectonic area of SE Asia at least two-thirds of the isolated carbonate platforms are documented to have formed over faulted antecedent highs with carbonate accumulation on many of these platforms coeval with local continued tectonism; i.e., many are syntectonic (Wilson and Hall, 2010). Isolated systems in SE Asia contain 83% of the hydrocarbon reserves within the regions carbonates.…”

“…Isolated systems in SE Asia contain 83% of the hydrocarbon reserves within the regions carbonates. With many of these platforms being tectonically influenced there is an economic driver to better understand the variable diagenesis of syntectonic platforms and any impact on reservoir potential (Wilson and Hall, 2010). Tectonics may influence carbonate systems through uplift, differential subsidence, or active faulting (Burchette, 1988;Wilson and Hall, 2010).…”

Diagenesis of Neogene Delta-Front Patch Reefs: Alteration of Coastal, Siliciclastic-Influenced Carbonates from Humid Equatorial Regions

“…Here, ''coastal carbonate'' refers to nearshore marine carbonate development along predominantly siliciclastic coastlines, such as in delta-front, fan-delta, or siliciclastic inner-shelf settings. The results of this study provide insights into patterns of diagenesis in coastal carbonate systems that may have broad analogs elsewhere (Hendry et al 1999;Nelson et al 2003;Wilson and Hall 2010;Wilson 2012).…”

Development and controlling factors of Upper Oligocene–Lower Miocene carbonate platforms and reefs in the Liyue Basin, South China Sea

“…During the Cenozoic, extensive shallow marine carbonate platforms developed in Southeast Asia in various passive and active tectonic settings (Fang, Liu, Li, Zhang, & Ding, ; Wilson & Hall, ; Wilson & Lokier, ; Wu et al, ; Wu, Zhang, Yao, & Wang, ). In the southern margin of the South China Sea (SCS), carbonate build‐ups developed on topographic highs during the Eocene to Early Miocene rifting phase (Fulthorpe & Schlanger, ; Lü, Wu, Yao, & Fulthorpe, ).…”