Continuing
NPA’s commitment to produce modern uniform
geological maps of the basins of China using satellite
imagery, we are now able to offer studies of the Tarim, Sichuan
and
Ordos basins. NPA have used high quality Landsat TM and
Landsat MSS data to map the basins (over 120 images used
in total).
All of the basins are known hydrocarbon producers which
are dominated by thrust and strike-slip tectonics on their
margins.
NPA have detailed the structural evolution of the basins,
outlining their plate-tectonic evolution and constructing
structural domain maps. On the smaller scale NPA have mapped
individual structures and outlined areas of hydrocarbon
potential.
The imagery for each of the basins has been digitally mosaiced
and produced as map sheets at various scales.
The imagery has then been interpreted on two scales: firstly
with respect to its plate tectonic evolution, taking into
account the main structural and stratigraphic events that
have affected the basin and the timing of such events, and
secondly on a more local scale in which the individual structures
are mapped. The latter has involved the categorisation of
thrust types (fault propagation folds, fault bend folds)
and the application of thrust models to real situations.
Results
Sichuan Basin
1. Production of a structural domain map outlining the main
tectonic units in the basin and detailing their time of emplacement
and importance in the hydrocarbon plays within the basin.
2. Identification of a triangle zone at the tip-line of
the thrust front, this has important implications for hydrocarbon
prospectivity.
Ordos Basin
1. The detailed mapping of drainage regimes and linears
within the basin enabled topographical anomalies and possible
basement highs to be mapped. These may indicated areas where
stratigraphic pinchouts occur (the most common form of trap
in the Ordos basin).
1. The study outlined the main structural domains and assessed
the importance of its tectonostratigraphic evolution to hydrocarbon
occurrence.
2. NPA are investigating the basin as part of their Thermal
Basin Screening project which aims to use satellite imagery
to map onshore seeps (please ask for details).
Overall the studies have enabled not only the plate tectonic
evolution of the basins to be understood but have also generated
models to produce 3D pictures of the structures present resulting
in an understanding of the hydrocarbon potential of the basins.
Products
Sichuan/Ordos: Six maps sheets at 1:500,000 scale (2 Sichuan,
4 Ordos).
1:1000,000 mosaics of the individual basins.
1:2000,000 mosaic of both of the basins
Tarim: Seven map
sheets at 1:500,000 scale.
Two map sheets (East & West) at 1:`1000,000 scale.
Single basin mosaic at 1:2000,000 scale.
Both studies are provided with clear-film structural geological
overlays, summary structure maps and a report with an accompanying
full colour A3 figures brochure. All of the data can also
be supplied digitally on a CD for the client to incorporate
into their own databases.
