seismic reflection at lang kawi

18
Seismic Reflection survey at Ayer Hangat Site to Investigate Shallow Subsurface Structures BY AMIN E KHALIL AND MOHD NAWAWI MOHD NORDIN

Upload: amin-khalil

Post on 29-Jul-2015

151 views

Category:

Environment


6 download

TRANSCRIPT

Page 1: Seismic reflection at lang kawi

Seismic Reflection survey at Ayer Hangat Site to

Investigate Shallow Subsurface Structures

BY

AMIN E KHALIL AND MOHD NAWAWI MOHD NORDIN

Page 2: Seismic reflection at lang kawi

Objectives• Investigate near structures with specially

emphasize on those responsible for hot water flow to the surface.

• Identify the subsurface occurrence of hot water in the study area.

• Explore the usage of Seismic reflection method for similar cases.

Page 3: Seismic reflection at lang kawi

Problem Statement

Development plans for geothermal resort requires

identification of the occurrence and network system

controlling the flow of hot water to the surface. Henceforth,

geophysical tools can serve to solve problems related to

such development plans.

Seismic reflection methods applied in the current study

aims to solve problems encountered during development of

the site under investigation.

Page 4: Seismic reflection at lang kawi

Location Map

Click icon to add picture

Page 5: Seismic reflection at lang kawi

Geology of the Area

Lithology

Page 6: Seismic reflection at lang kawi

Regional Geology(Ali, 2008)

Page 7: Seismic reflection at lang kawi

Instrumentation

Page 8: Seismic reflection at lang kawi

Methodology

Pullan et al, 1991.

Page 9: Seismic reflection at lang kawi

Previous Study(Ibrahim, 2014)

Page 10: Seismic reflection at lang kawi

Survey Layout

Survey is carried out using land streamer with 24 geophones at 1 m interval. Source offset is 5m. 49 shots gather were acquired at 1m interval.

Page 11: Seismic reflection at lang kawi

Software Used for analysis

In the present work we used two open source and free softwares. These softwares are:

1- Obspy: Python suite for seismological applications. We used OBSPY to convert the SEG2 format of the field recordings into SEG-Y files.

2- Seismic Unix (SU) to process the data. SU is used under UBUNTU in the present study.

Page 12: Seismic reflection at lang kawi

Sample Raw Data

Sample Window of the data acquired

Page 13: Seismic reflection at lang kawi

Common offset gather

Page 14: Seismic reflection at lang kawi

Common offset gather

Page 15: Seismic reflection at lang kawi

28 m common offset gather after filtering and tapering

Page 16: Seismic reflection at lang kawi

25 m common offset gather after filtering and tapering

Page 17: Seismic reflection at lang kawi

Discussion

• Seismic reflection surveying is applied to Ayer Hangat area to help identifying the geothermal aquifer.

• 49 shots with 1m intervals are conducted using land streamer.• Data were analysed using both OBSPY and Seismic Unix • Common offset gather shows the possible location of ground

water or geothermal aquifer in the study are.• The velocity analysis is in the processing stage to determine

the depth of the aquifer.• From the analysis it is demonstrated that seismic reflection

can be used for geothermal aquifer exploration.

Page 18: Seismic reflection at lang kawi

Thank You