During the Miocene, extensive carbonate deposition thrived over wide latitudinal ranges in SoutheastAsia despite perturbations of the global climate and thermohaline circulation that affected the Asian continent. nevertheless, the mechanisms of its emergence, adaptability in siliciclastic-dominated margins and demise, especially in southern South china Sea (ScS), are largely speculative and remains enigmatic along with a scarcity of constraints on paleoclimatic and palaeoceanographic conditions. Here we show, through newly acquired high-resolution geophysical data and accurate stratigraphic records based on strontium isotopic dating, the evolution of these platforms from ~15.5-9.5 Ma is initially tied to tectonics and eustasy, and ultimately, after ~9.5 Ma, to changes in the global climate patterns and consequent palaeoceanographic conditions. our results demonstrate at least two paleodeltas that provided favourable substratum of elevated sand bars, which conditioning the emergence of the buildups that inadvertently mirrored the underlying strata. We show unprecedented evidences for ocean current fluctuations linked to the intensification of the Asian summer monsoon winds resulting in the formation of drifts and moats, which extirpated the platforms through sediment removal and starvation. this work highlights the imperative role of palaeoceanography in creating favourable niches for reefal development that can be applicable to carbonate platforms elsewhere.A gargantuan modification of the planetary climate system and the thermohaline circulation patterns occurred in the Cenozoic with the inflection point being diffused from exceptionally critical tectonic processes that affected Asia 1,2 . At ca. 24 Ma, in close proximity to the Oligocene-Miocene boundary, the continent experienced a transformation of climatic processes from a latitudinal zonal circulation pattern to a monsoon-dominated configuration along with the evanescing of an extensively prevalent subtropical-aridity across Asia and the inception of aridity that was exclusively restricted to the hinterland of eastern Asia 3 . The Asian continent experienced a dynamic climate transition that was instigated by the Paleocene-Eocene collision of the Indian Plate with Asia and the resulting progressive uplift of the Tibetan Plateau (TP). This caused an array of feedbacks that significantly strengthened monsoon-inducing atmospheric circulation with each of its major orogenic pulses 4 (i.e., at (i) ca. and (iii) ca. 15-10 Ma [refer to Fig. 1 for (ii) and (iii)]). Over a span of ~30 Ma, the stepwise exhumation of the TP governed an accelerated amplification of firstly, the Indian Summer Monsoon (ISM) and the Somali Jet with the initial pulse of uplift; secondly, the Southeast Asian Monsoon, the East Asian Summer Monsoon (EASM) and the East Asian Winter Monsoon (EAWM) with 40% uplift of the TP; and lastly, the further intensification of the EASM and EAWM with 80% uplift of the TP 5,6 (Fig. 1). This last uplift

The internal architecture and evolution of isolated carbonate buildups rely on multiple forcing factors, including tectonics and eustatic fluctuations. These parameters control the developmental phases of carbonate buildups such as initiation, growth, and termination stages, and give insights into other morphologic patterns such as backstepping and exposure events. The current study shows the evolution of a Middle Miocene isolated carbonate buildup of Central Luconia in the southern South China Sea, and describes it from large‐scale to very fine detail (km to mm) utilizing newly acquired (2016) 3D seismic data along with core lithofacies and thin sections. The buildup morphology and seismic facies are linked to core facies that can help to uncover the complex development of the carbonate platform. Core‐seismic calibration was used to create maps illustrating carbonate depositional settings for each stratigraphic unit. Here, we identified five seismic units that constitute the main stratigraphic stages of buildup development: (a) initiation as several isolated buildups, (b) coalescence, progradation, and aggradation, (c) aggradation and retrogradation associated with minor backstepping events and major karstification events, (d) retrogradation associated with major backstepping events, and (e) drowning stage. Our results demonstrate that Miocene reefal evolution and buildup architecture in Central Luconia were distinctly affected by diverse endogenic and exogenic processes. The initiation of localized carbonate growth appears to be strongly controlled by the morphology of the pre‐carbonate basement of Central Luconia where the SSW–NNE horst and graben structures were inherited from the poly‐stage opening of the South China Sea during the Early Miocene. Furthermore, sea‐level fluctuations, local and regional tectonic events during the Middle Miocene controlled the rates of accommodation changes, which directly impacted the stratigraphic architecture of the platform. The detailed seismic and sedimentological study documented in this work will benefit the understanding of the paleogeographic and stratigraphic evolution of carbonate buildups in the Luconia region of SE Asia, and in the current and future exploration for substantial conventional resources.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

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