Hydrocarbon seeps cause chemical and mineralogical alterations at the surface,
which can be identified geologically but also detected by remote sensing techniques.
This work aimed at detecting mineral alteration induced by hydrocarbon seeps in a
sandstone formation in Rufiji basin (Wingayongo), South Coast Tanzania. For this
study, rock samples collected during fieldwork were petrographically analysed and
the multispectral ASTER data was downloaded and utilized to characterize the
identified alteration minerals in the Wingayongo sandstone. The area is covered by
medium grained gray to brown chocolate bituminous sandstone, which acts as
reservoir rock but with no cap rock overlaying it. The contact between sandstone
layers were identified and defined as the main source of hydrocarbon migration
pathways. Large area of this sandstone is bleached indicating discoloration of ferric
iron into ferrous iron. Elemental sulfur greenish yellow in color together with
sulphur smell were identified around the seep. Petrographic analysis (XRD and
Thin Section) have shown high value of ferrous iron but there was no evidence of
clay (kaolinite) or carbonate minerals. Remote sensing spectral signature through
band ratio enhancement indicated the presence of siderite material, altered
vegetation together with un-vegetation signals. The observed signals are potential
vectors for oil seeps. Other prospective areas were identified using similar spectral
signals in the surrounding areas. The use of more than one dataset together with the
use of more powerful remote sensing technique are recommended to overcome
challenges in interpretation and issues of scale of alteration and other controversor.
The Public Access, L (2021). Detection Of Hydrocarbon Seeps Using Remote Sensing Technique In The Rufiji Onshore Basin. Afribary.com: Retrieved May 13, 2021, from https://afribary.com/works/detection-of-hydrocarbon-seeps-using-remote-sensing-technique-in-the-rufiji-onshore-basin
Library, The Public Access. "Detection Of Hydrocarbon Seeps Using Remote Sensing Technique In The Rufiji Onshore Basin" Afribary.com. Afribary.com, 27 Apr. 2021, https://afribary.com/works/detection-of-hydrocarbon-seeps-using-remote-sensing-technique-in-the-rufiji-onshore-basin . Accessed 13 May. 2021.
Library, The Public Access. "Detection Of Hydrocarbon Seeps Using Remote Sensing Technique In The Rufiji Onshore Basin". Afribary.com, Afribary.com, 27 Apr. 2021. Web. 13 May. 2021. < https://afribary.com/works/detection-of-hydrocarbon-seeps-using-remote-sensing-technique-in-the-rufiji-onshore-basin >.
Library, The Public Access. "Detection Of Hydrocarbon Seeps Using Remote Sensing Technique In The Rufiji Onshore Basin" Afribary.com (2021). Accessed May 13, 2021. https://afribary.com/works/detection-of-hydrocarbon-seeps-using-remote-sensing-technique-in-the-rufiji-onshore-basin