Facies Analysis Using Biostratigraphy Data and Also Development andControlling Factors of Miocene Carbonate Buildups,Central Sulawesi

摘要

Quantitative analysis of facies in a complex depositional environment is have some difficulty in termsof ability to constrain the data available into easily recognizable and reproducible facies types.One ofthe most challenging environments is the shallow water carbonate depositional system.Using subsurfacedata,a facies class of Tertiary carbonates of Banggai Basin was established to allow reproducible faciesdescriptions by multiple workers.The analysis based on core data from Research area (about 2,000 feetof core from five wells)Tertiary subsurface carbonates of the Research area,range in age from Late Miocene to Early Plioceneand are comprised of diachronously deposited shallow water platform carbonate build-ups and associatedwith detrital carbonate sediments.Time equivalent carbonates of the Mentawa member Limestone,showing the same range ofenvironments.On the basis of faunal content,grain types,sedimentary texture,and sedimentary structure,Autochthonous facies types represent reef margin,platform interior,and slope environments ranging fromshallow-water,reefal boundstone and rudstone to planktonic foraminifera wackestone and packstone.Allochthonous facies represent grain-dominated,detrital facies types,intercalated within mud-dominatedto graindominated facies types; rich in planktonic foraminifera.Age diagnostic,large benthic foraminifera (LBF),planktonic foraminifera,and calcareousnannoplankton enable the correlation of subsurface data and allow high-resolution sequence stratigraphiccorrelation throughout the research area.Integration of subsurface data leads to more insightful and realisticgeological models of subsurface stratigraphy.The sequence stratigraphic development of the subsurfacePaleogene in Research area,Central Sulawesi,was define using well cuttings,core data and wireline logstied into largely published biostratigraphic and available seismic data.Large benthic foraminifera assembladges used for detailing depositional environment also associatedwith reef connected environment.Diagenetic process indicating creation and destruction of carbonateporosity,due to presence of marine,fresh water,pressure and temperature that present in term of tectonicand subsidence.Some of the micritization,recrystallization,and neomorphism.