Abstract:

The Wulanhada-Chuludaban area in Inner Mongolia is located in the middle section of the Zhalantun volcanic rock-type uranium mineralization prospecting zone and is one of the hydrothermal uranium polymetallic mineralization clusters in Northern China. The area experienced intense and frequent Mesozoic volcanic eruptions, providing excellent geological conditions for mineralization and promising exploration prospects. Through the collation of previous data, comprehensive mapping, and uranium geological survey and evaluation, the geological characteristics and ore-controlling factors of volcanic rock-type uranium deposits in the Wulanhada-Chuludaban area have been preliminarily summarized. Through drilling verification, it is found that the volcanic rock-type uranium deposits in the research area can be classified into two types based on the main ore-controlling factors: subvolcanic rocks and altered fracture zones. It is believed that the peak period of uranium mineralization in the research area was from the Late Jurassic to the Early Cretaceous, mainly concentrated between 149 and 99 Ma, with the characteristics of a large time span and multiple stages. Uranium mineralization anomalies are mainly distributed along the NE-trending F_W2 trans-shell faults and are mostly found in the NE and NW-trending secondary faults and structural fracture zones. Uranium mineralization is mainly controlled by uranium source, strata and structure, subvolcanic rocks, and hydrothermal alteration. Hematitization, fluoritization, and silicification can be used as direct exploration indicators. The next exploration work should focus on searching for altered fracture zone-type uranium mineralization on both sides of the NE-trending F_W2 ore-controlling faults, and secondly, strengthen the exploration of uranium mineralization around volcanic structures and subvolcanic rocks.

Key words: Wulanhada-Chuludaban')">Wulanhada-Chuludaban, characteristics')">mineralization characteristics, direction')">prospecting direction, ore')"> volcanic type uranium ore, type')">subvolcanic type, fracture zone type')">altered fracture zone type