Oligocene Cyclic Sedimentation Deduced from Taphonomic Analysis of Molluscs in Lacustrine Deposits of the Pematang Group, Pesada Well, Central Sumatra Basin
Journal Title: Journal of Mathematical and Fundamental Sciences - Year 2016, Vol 48, Issue 1
Abstract
The Oligocene cycle of Pesada Well, Central Sumatra Basin, Indonesia is composed of a deepening-upward series of depositional cycles in a lacustrine environment affected by oscillations of the water level. Taphonomic analysis of gastropod molluscs was used to interpret the cycle architecture of the Brown Shale (Pematang Group). Four types of shell concentrations were identified. The early transgressive deposit has a distinct erosion surface at the base, contains concretions, is formed of coarse-grained sediment with abraded and broken shells, and is interpreted as reworked deposits. The late transgressive deposit contains a hiatal concentration formed by continuing lake level rise, with many complete shells preserved in life position. The maximum transgressive deposit has complete shells in life position or that have been transported, as well as juvenile molluscs and broken shells. The early regressive deposit contains alternating shell-rich and shell-poor layers. Since the lacustrine system shows no tectonic effects and also no marine influenced indications, the seven sedimentary cycles identified in the Pesada Well are likely to have been affected by oscillations between monsoonal and dry periods.
Authors and Affiliations
Aswan Aswan, Satia Graha, Dodi Suryadi, Taufan Wiguna, Sri Iman Qivayanti
Thickness Effect on Fluctuation of Electron States in Thin Film and Implications for Lattice Constant Change Due to Size Reduction
We propose a model for predicting the fluctuation of electron states in thin films as a function of film thickness. The model is derived based on the assumption of the existence of potential barrier fluctuation on the fi...
Trees with Certain Locating-chromatic Number
The locating-chromatic number of a graph G can be defined as the cardinality of a minimum resolving partition of the vertex set V(G) such that all vertices have distinct coordinates with respect to this partition and eve...
Influence of Various Precursor Compositions and Substrate Angles on ZnO Nanorod Morphology Growth by Aqueous Solution Method
ZnO nanorods were synthesized on silicon wafer substrate with a seed zinc layer using the aqueous solution method. The influence of various precursor compositions on the morphology of the ZnO nanorods, with substrate ang...
Inclusion Properties of Orlicz and Weak Orlicz Spaces
In this paper we discuss the structure of Orlicz spaces and weak Orlicz spaces on R^n. We obtain some necessary and sufficient conditions for the inclusion property of these spaces. One of the keys is to compute the norm...
Inhibition of Mammary Gland Cancer Development by Propolis and Mangostin in Female Mice Balb/C
The development of breast cancer involves many processes, including angiogenesis and metastasis. Some factors play a major role in angiogenesis, such as HIF-1α, and in metastasis, such as FAK and Wnt2. The aim of this st...