City and Regional planning

Remote Sensing In Petroleum Seepages Detection

Instructor:Dr. Baqer Al-Ramadan

By:Asaad AbdulraziqID # : g201103590

Dec, 27, 2011

Outline

Introduction

Objectives

Case study 1

Case study 2

Results

Discussion and Conclusion

IntroductionObjectives

Case study 1

Case study 2

Results

Discussion and Conclusion

Introduction

Remote sensing (RS) is collection of data without actual contact with the object being studied

Remote sensing is a very important tool in petroleum exploration and usually used in early stage of exploration

RS can give a good idea a bout general geology, structure, and rock type

Fig. (1):Satellite images of the Midyan region showing localities and geological features

But sometimes Remote Sensing can detect petroleum seepages

So,What is the concept & causes of petroleum

seepage?Why it’s important?How Remote Sensing can help?

Introduction:

When oil and/or gas escaping from the subsurface (reservoir rock) along the fractures and permeable beds to the surface that called petroleum seepage

Seepage can make some traces in the earth surface and the sea surface

The remote sensing target these traces

The seepage could be microseepage or macroseepage

Concept of seepages:

Fig (2): Show petroleum seepage through faults, fractures as well as stratigraphic boundaries (modified from Schumacher, 1999).

Concept of seepages:

Oil seepage:

Seepages is a direct indication to presence of oil and gas in the subsurface

Also, it largest source of air pollution (greenhouse gases)

e.g. in the Santa Barbara Channel of Californiait is estimated five million cubic feet of natural gas seep through the ocean and into the air each day, or almost two trillion cubic feet per year

Important of petroleum seepage:

Fig(3): Global data base show global distribution of petroleum seepages (Etiope, 2009).

Important of petroleum seepage:

Introduction

ObjectivesCase study 1

Case study 2

Results

Discussion and Conclusion

The aim of this term paper is:

To locate seepages of petroleum using remote sensing techniques

To explain the possible causes of seepage To identify the excellent Remote sensing tool

for detection To provide the impact of petroleum seepage

on the mineral composition (called alteration)

Objective:

Introduction

Objectives

Case study 1

Case study 2

Results

Discussion and Conclusion

Fig (4): Map show the location of study area (Dave, et al., 2011).

Case study 1:Detection of Natural Hydrocarbon Seepages Using SAR

Technology and Associated Subsurface Studies in Offshore Mahanadi Basin, India for Delineation of Possible Areas of

Hydrocarbon Exploration

Using Radar images, the radar have SAR sensor to measure backscatter radiations, the output of the radar images appear like black and white depend on the surface covered in the survey

Some available geophysical data (Free Air Gravity, Seismic, and Geochemical data)

Methodology:

Table (1): Classification of identified hydrocarbon seepages based on their degree of confidence (Dave, et al., 2011).

Results:

Fig (5): show the results of combining Radar data with geophysical data (Dave, et al., 2011)

Results:

Introduction

Objectives

Case study 1

Case study 2

Results

Discussion and Conclusion

Fig (6): Structure sketch of Kuqa depression basin (Shi et al., 2010).

Case study 2:MAPPING HYDROCARBON SEEPAGE-INDUCED ANOMALIESIN THE ARID REGION, WEST CHINA USING MULTISPECTRAL

REMOTE SENSING

Remote sensing techniques:Landsat Thematic Mapper (TM)Landsat-7 enhanced thematic mapper plus (ETM+)ASTER images (Advanced Spaceborne Thermal Emission and Reflection Radiometer)

Geological techniques:Scanning Electron Microscope with Energy Dispersive Spectrometer (SEM/EDS)X-ray diffraction (XRD)

Methodology:

Fig (7): ASTER images of the study area. (a) Grayscale image of ASTER band ratio 2 ⁄ 1. (b) Grayscale image of ASTER band ratio 4 ⁄ 9. (c) False color composite image of ASTER band ratio 2 ⁄ 1 (d) Enlarged ASTER false color composite image (Shi et al, 2010)

Results:

Fig. (8): Photographs showing surface alteration and oil seepage along the Qiulitage anticline. (a). Surface of the altered rocks. Note the alteration of red beds: altered rocks appear as greyish green, yellowish green along the crest of the anticline. (b) Multiple sets of gypsum veins. (c) Surface of the altered rocks in a large scale (Shi et al, 2010).

Field studies:

Fig (9): (f) Oil macroseepage along the Qiulitage anticline (Shi et al, 2010).

Field studies:

Introduction

Case study 1

Case study 2

Results

Discussion and Conclusion

Objective

According to the Radar image results we have twenty-sixseepage locations had been identified but it different in the degree of confident medium and low degree of confident all these seepages in along facture zone or fault and this fracture allow escaping oil and gas to the sea surface, and give high degree of confident in repeated area

In the subsurface and multi-data satellite data show high extension of this oil stain that indicate lighter seepage of oil

Geochemical data show the gases origin, and it indicates the presence of condensate or wet gas

Discussion and conclusion:

Results showed that ASTER band ratios of 2/1 and 4/9 can reveal successfully mineralogical alterationsinduced by hydrocarbon seepages

The altered rock show variable degree of oxidationappear as bleached red bed and secondary carbonates

Also the result of lab work specially work under microscope show in altered rocks micritic carbonate, calcite cement, and crystallization are very common instead of hematite that is very common in the unaltered samples of red sandstone

Discussion and conclusion:

Fig (10): (A) Processes by which microseeping hydrocarbons migrate from the reservoir to the surface through faults, fractures as well as stratigraphic boundaries (modified from Schumacher, 1999). (B) Generalized model of hydrocarbon induced geochemical alterations of soils and sediments (modified from Schumacher, 1996).

Discussion and conclusion:

Petroleum seepage Possible causes Important Remote sensing tools Using any available data Impact of oil seepage on the rocks

Summary:

Thanks for Listening