Sains
Malaysiana 46(11)(2017): 2109-2118
http://dx.doi.org/10.17576/jsm-2017-4611-11
The
Application of Airborne Geophysics Data for Rapid Regional Geological Mapping
in Northwestern Angola
(Aplikasi Data Geofizik di Udara untuk Pemetaan Geologi Serantau di
Barat Laut Angola)
HONGRUI
ZHANG1,2*, PENGFEI JIA2, XU ZHANG2 &
ZHIGANG WANG2
1Institute of Mineral Resources, Chinese
Academy of Geological Sciences, Beijing 100037, China
2CITIC Construction Co., Ltd.,
Beijing 100027, China
Diserahkan:
29 Januari 2017/Diterima: 10 Jun 2017
ABSTRACT
Airborne prospecting (spectrum, magnetics) measurement
is an effectively auxiliary approach for geological mapping. It effectively
measures the magnetic field characteristics and the surface contents of the
most common three radioactive elements (K,eU and eTh) of nature in the research
area. Given the significant diversities of magnetic characteristics and the
radioelements’ contents of different lithological units, these can be applied
into the mapping of shallow overburden area. Ternary MAP is a compound imaging technology, providing the
radioelements contents a simultaneous display on the same pixel. Based on
colour differences, this technology can identify different lithologies and
clithofacial changes in the same lithological unit effectively in a certain
area. With aeromagnetic data conversion and integrated spectrum images, a good
effectiveness of 1:250,000 lithological-structural mapping has been achieved in
the research area of Northwestern Angola.
Keywords: Aeromagnetics; data processing; rapid
geological mapping; spectrum; 1:250,000
ABSTRAK
Pengukuran prospeksi (spektrum, magnetik) di udara
adalah pendekatan tambahan yang berkesan untuk pemetaan geologi. Ia secara
berkesan mengukur ciri medan magnet dan kandungan permukaan tiga elemen
radioaktif (K, eU dan eTh) yang paling biasa di kawasan penyelidikan.
Memandangkan ciri kepelbagaian magnetik yang ketara dan kandungan radiounsur
daripada unit litologi berbeza, ini boleh digunakan dalam pemetaan kawasan
tebukan cetek. Ternari MAP adalah
teknologi pengimejan kompaun, memberikan kandungan radiounsur suatu paparan
serentak pada piksel yang sama. Berdasarkan perbezaan warna, teknologi ini
dapat mengenal pasti pelbagai lapisan dan perubahan klitomuka dalam unit
litologi yang sama secara berkesan di kawasan tertentu. Dengan penukaran data
aeromagnet dan imej spektrum bersepadu, keberkesanan yang baik 1: 250,000
pemetaan struktur litologi telah dicapai di kawasan penyelidikan Barat Laut
Angola.
Kata kunci: Aeromagnet; pemetaan
geologi yang cepat; pemprosesan data; spektrum; 1: 250,000
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*Pengarang untuk
surat-menyurat; email: zhhr2214@163.com