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Remote Sensing Image Feature of Uranium Ore in China

Yunzhong.Xie,Kexu.Ding and Mingsong.Li
Airborne Survey and Remote Sensing Center of Nuclear Industry China
Shijiazhang City 050002

The research of remote sensing image feature of uranium ore in china, based on more than twenty years uranium geology work, has been carried out in 43 varied regions, So a total of 171 deposits have been studied by 66 persons for two years. In this study, we have summarized the elements of image interpretation and established six image-geology patterns, also reclassified into ten types. This research has verified the effect applying remote sensing image feature on study of geological ore-controlling environments and evolutions; And we have predicted 120 favorable areas for prospecting by re-recognizing metallogenetic regulation. Then all maps, including remote sensing images, geological interpretation maps, images features maps and typical image maps, and image feature illustrates of each targets have been complied into one book called "Remote Sensing Image feature of Uranium Ore in China".

The research of remote sensing feature depended on deferent spectral signature of surface objects. The remote sensing characteristics of uranium deposit types vary along with their geologic characteristics. So, the image features can reflect uranium metallogenesis.

Main deposit types of uranium ore in china
In china, many types of uranium deposit have been identified. Basing on ore-bearing hostrock considering the origin of deposit, we would divide uranium deposits into the following types: granite, volcanic rock carbonate-siliceous-pelitic rock, pegmatite-granite, alaskitic and migmatite uranium deposits.

2. The remote sensing image feature of uranium ore
There are much data of metallogenetic characters in the uranium deposit regions. The deposit element, such as color, tone, grain, linear, ringlike and landscape, be reflected on the remote sensing images, which could make up a bright and colorful picture with the lines combination and regular veined patch and macro-regionalization landscape. The map can reflect amply controlling factor, metallogenetic process, ore-type feature and exploration guide.

The main remote sensing image combination types of uranium ore
Linear image factor, ringlike image factor, tonal image factor, grain image factor, landscape image factor.

The main remote sensing image combination types of uranium ore
Uranium deposit was caused for combination varied geological processes and metallogenesis. Such the remote sensing image features show many image factors combination. The combination types of image elements concerning closely uranium metallogensis, which have been drawn from studying on 171 deposits, are following.
  1. Linear structure is very developing in the uranium deposit region. Esp. In the granite,the volcanic rock, the pegmatite and migmatite uranium deposits region. The linear structure is usually predominant. The action of the linear structure itself and the other linear structures combination have following difference expression forms:
    • Striped concentration linear structures combination--deep-seated fault zone
    • Conmbination predominant and bulk- downfaulted zone type
  2. Combination linear structure and bulk- downfaulted zone type The image feature of linear structure and geological block grain is main type.
    • Combination linear structure and streaky block- granite downfaulted zone
    • Combination linear structure and ringlike image- granite downfaulted zone
    • Combination linear structure and basin landscape- Meso-Cenozoic red basin downfaulted zone

    3. Downfaulted zone is main uranium deposit type.

  3. Combination streaky structure and linear structure- folded and faulted compound type
    The circuitous lines or the stripped geomorphological streaky structure are showed in the image. The direct of axis or the oblique-cutting linear strcture, which both benefit the formation of folded-structure compound uranium deposit, have developed at the one wing or one end of folded.
  4. Combination tectonic "tie" -tectonic converging compound type
    The uranium-ores are always formed at the place where two groups or above linear fault and ringlike image converges. So tectonic "tie" is important metallogenesis image features.
  5. Combination ringlike image- anticline(vault)type
    Blocky mountain masses whose grain is sparse are distributed around the picture. However, ringlike image is located on the middle of picture whose grain is close, terrain relative lower. The compound location if ringlike image and the core of anticline, which is mutual-cutting location of NE, NNE, NS-fault is favorable location for uranium metallogenetic.
  6. Combination landscape and pattern- sandstone uranium deposit type
    • Combination landscape and pattern- synsedimentary subsequent accretion type
    • Combination geographic landscape texture- oxidized zone sandstone type
Image features of uranium ore and uranium metallogenesis
Image features are manifestation metallogenetic products. Uranium metallogenesis are inner factor of image features formation. Through studying image features of uranium, we realized that it has great arrest on approaching uranium metallogenesis.
  1. Applying the remote sensing image features to analysis geological metallogenesis environmental
  2. Applying the remote sensing image features to analysis geological metallogenesis evolution Image features have plentiful materials for analyze geological evolution metallogenesis, including linear image which reflects geological tectonic movements, tones abnormality which show thermal events, pattern landscape which manifests metamorphism and so forth.
  3. Applying abundant remote sensing image features to confirm the theory of uranium metallogenesis

    Deeply fault often play a dominant controlling role for formation of uranium ore. The function of NS structure is common and important effect. Tectonic "tie" is indispensable factor for uranium deposit position. These theories were confirmed by analyzing image features.
  4. Applying the remote image features to establish model of uranium prospecting image.
  5. Carrying prognosis of prospecting potential.