Satellite‐ and field‐based facies mapping of isolated carbonate platforms from the Kepulauan Seribu Complex, Indonesia

Abstract

Quantitative facies models from modern carbonate are essential for the interpretation of their fossil counterparts. The isolated carbonate platforms of the Kepulauan Seribu archipelago has many atoll‐like islands with reef belts exposed to bidirectional monsoon winds. Statistical analysis based on texture and composition reveal that there are four sedimentary facies; coral grainstone, coral packstone/grainstone, coral‐mollusc packstone and mollusc wackestone. The occurrence of mollusc wackestone in the lagoon is controlled by water depth, while the sand apron and reef front do not show significant facies separation with water depth. The co‐occurrence of these different facies in the same depth window is contrary to the common thought that changes in bathymetry should be reflected in facies changes. The studied reef systems therefore show aspects of random and ordered facies distribution with respect to water depth. A satellite derived environmental facies map generated by an image analysis algorithm indicates that environmental facies distribution is mainly controlled by water depth, density of seagrass cover and coral abundance. The sand apron can be subdivided into three environmental facies with no, sparse and dense seagrass cover. The deeper water zone can be separated into shallow and deep subtidal parts of lagoons and platform margins. In the lagoon, satellite derived environmental facies directly correlated with sedimentary facies. No direct correlation of environmental facies to sedimentary facies was possible in the sand apron due to the heterogeneity and complexity of the environment. However, the mean sediment grain size is significantly smaller in areas of the sand apron colonized by dense seagrass. This study aims to contribute towards a better understanding of modern equatorial Southeast Asian carbonate systems, delineate modern carbonate facies based on sediment texture and composition with the aid of multivariate statistical analysis combined with statistic based satellite mapping, and give insights regarding the correlation between depositional facies and water depth.

Hardened faecal pellets as a significant component in deep water, subtropical marine environments

“…Volumetrically, they form up to 67% of the fine to medium sand fraction and on average ~2% of the total sediment of the entire interval. The abundance of pellets in these relatively deep-water temperate carbonates is therefore similar or higher than most tropical carbonate shoals and shallow water platforms in the Indo-Pacific region (Gischler, 2011;Utami, Reuning, & Cayharinin, 2018). Many carbonate platforms and shoals in the Caribbean (Milliman, 1967(Milliman, , 1969 have higher peloid contents compared to IODP site U1460, but several have similar or even lower peloid abundances, for example the Dry Tortugas shoal on the distally steepend ramp of the west Florida shelf or the Turneffe Islands platform off Belize F I G U R E 8 Bathymetric profile across the outer ramp/shelf (modified after James et al, 1999, for position see Figure 1).…”

Geomorfologi Terumbu Karang Dan Habitat Bentik Gugusan Pulau Biawak, Indramayu: Integrasi Studi Citra Satelit Dan Sedimen Permukaan

“…Kondisi tersebut sesuai dengan Spalding & Grenfell (1997) serta Vescei (2004), yang menyampaikan bahwa koral merupakan komponen utama dalam lingkungan karbonat neritik. Tekstur dan komposisi sedimen di Gugusan Pulau Biawak mirip atau sebanding dengan tekstur dan komposisi sedimen di Gugusan Pulau Seribu, DKI Jakarta (Utami et al, 2018) dan Gugusan Pulau Karimunjawa, Jawa Tengah (Solihuddin et al,2019).…”

Sedimentary Environment of a Modern Carbonate Platform of Karimunjawa Islands, Central Java

“…Studies in the Indonesian carbonate environments have been typically focused on their biota and ecological aspects (Tomascik et al, 1997;Cleary et al, 2005;Becking et al, 2006;Renema, 2006aRenema, , 2006b with limited studies linked to an understanding of their sedimentology. Detailed sedimentological studies of modern carbonate systems are restricted to those of Kepulauan Seribu, offshore Jakarta, demonstrating bioclastic assemblages on the predominantly siliciclastic shelf sediments (Park et al, 1992(Park et al, , 2010Jordan, 1998;Utami et al, 2018). Moreover, Madden et al (2013) pointed out the dominant bioclastic carbonate sands with grainstone to grain-rudstone texture in Kaledupa and Hoga atolls, Wakatobi Islands.…”

“…Model from the small-scale patch reef complex of Kepulauan Seribu (Utami et al, 2018) or atoll reefs in Wakatobi (Madden et al, 2013) might not be wholly analogous and applicable to the carbonate systems elsewhere in Indonesia. The differences may relate slightly to ecological conditions and partly to geomorphic and oceanographic processes since sedimentology on reef platform is closely associated with environmental conditions (Smithers, 1994;Gischler and Lomando, 1999).…”