SEMINAR: MGG Student Seminar - Tuesday 2/22/11 - Qiong Zhang and Rani Sianipar

[Kelly Gibson <kgibson@rsmas.miami.edu>]

MGG Student Seminar

Tuesday, Feb 22

12:00pm CIMAS Conference Room

Qiong Zhang: How to live with the unpredictable earthquake? ----- Know more about seismic hazard assessment 

Large earthquake and the subsequent effects are devastating. One of the scientific challenges is to learn more about giant earthquakes and the occurrence processes. Since the earthquake cannot be predicted at present, we can only evaluate the potential regions of future earthquakes and estimate the possible damage scenario to reduce hazard loss in case earthquake occurs.

I will present how the deterministic and probabilistic seismic hazard analyses are utilized to produce seismic hazard map after the ground motion and reoccurrence interval are determined.  The Western, Central and Eastern US seismic hazard will be compared.  Urban earthquake hazard maps are going to be discussed.

Successful examples of promoting earthquake awareness and preparing for major earthquakes are mentioned.

Overall, it will be a general study about how seismic hazard analysis are operated and applied.

Rani Sianipar:

Carbonate reservoir of lower Kujung Formation is bioclastic carbonate rocks that are deposited in deeper environment. Quality of bioclatic carbonate rocks is highly heterogeneous, controlled by depositional facies, mineralogy and diagenesis. Detail study of this carbonate rocks is necessary to understand heterogeneity of carbonate rocks. More importantly, to understand reservoir characterization that will influence petrophysic parameter for volumetric calculation. Subsurface data, which are from “R” Well in East Java Basin, includes 282 ft conventional core, 40 thin sections of the conventional core, and 5 different types of well logs. The data is studied by conducting macroscopic and microscopic description to conventional core in order to achieve their depositional facies pattern and diagenesis history and also by analyzing the well logs qualitatively to determine the reservoir zone. This information can become a reference for next development plan of “R” field. Description of subsurface data in “R” well shows development of lithofacies genetically from lower to upper portion are middle shelf – inter reef lagoon – near reef – inter reef lagoon – near reef – inter reef lagoon with relative sea level changes from deepening to shallowing then relative stabile.  Those lithofacies are interpreted as gravity flow deposits that are deposited on isolated platform. Based on petrography and petrology description, there is a boundary of lithofasies with different diagenesis history. Lithofacies, which are deposited in early Late Oligocene, are influenced by cementation in marine water phreatic zone during early diagenesis then compaction, cementation and minor dissolution happened in burial zone during late diagenesis. Lithofasies, which are deposited in middle - late Late Oligocene, are altered by micritisation, cementation, solution, and neomorphism in marine phreatic - fresh water phreatic zone during early diagenesis then dolomitization, compaction and minor solution happened in burial zone during late diagenesis. Based on qualitative analysis of “R” well log, the lithology of lower Kujung Formation, which is deposited in early Late Oligocene, is calcareous shale with intercalation of limestone whereas the upper Kujung Formation are limestones. Kujung carbonate rocks of “R” well consist of 8 gas reservoir zones and 8 non-reservoir zones. Their porosity values range from 5,2% to 9,4% with interparticle, moldic and fracture as their major porosity type in reservoir zone.

 

 

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Kelly Gibson
Graduate Student, Marine Geology and Geophysics
Rosenstiel School of Marine and Atmospheric Science, University of Miami
4600 Rickenbacker Cswy Miami FL, 33149

Office: 305.421.4810 x6
Email: kgibson@rsmas.miami.edu