Up to now, the regional geological surveys of the working area and its periphery1∶ 500,000 and1∶ 200,000 have all been covered. These works were mainly concentrated before 1980s, and were completed by geological exploration units in Inner Mongolia Autonomous Region. While carrying out the regional survey of1∶ 200,000, the heavy sand and metal quantity were measured, and the corresponding polymetallic heavy sand and metal quantity anomalies such as copper and gold were delineated, which provided basic geological data for the prospecting work in this area.
1∶ 50,000 regional survey began in the late 1980s and early 1990s, and it is one of the earliest regions in China to carry out large-scale mapping. Up to now, the geological mapping of1∶ 50,000 covering the whole area has been basically completed, the regional stratigraphic units have been divided, and the regional magmatic activity series has been established. The corresponding research has also made many new progress, which provides abundant data for studying the regional tectonic evolution in this area.
On the basis of basic geological mapping, regional geophysical and geochemical exploration has been carried out in an all-round way. The gravity survey of Inner Mongolia 1 ∶ 1 Wanbuge was completed in 1970s and 1980s, and the gravity anomaly map and comprehensive research report of1∶/Wanbuge were submitted in 1990. 1∶ 200,000 river system geochemical exploration covers the whole area, and large-scale geochemical exploration has been carried out in some key sections, which has accumulated rich geological achievements and become the main basic geological data and basis for later geological and mineral exploration.
3. 1.2 mineral exploration work
Mineral geological exploration in this area started early and has a long history. In this area, Wendumiao iron mine and Bainaimiao copper-gold mine are one of the earliest endogenetic metal deposits found in this area, and the research degree is also very high. So far, many gold polymetallic deposits (spots) such as Baiyinhar and Hadamiao have been discovered in this area. But on the whole, the results of mineral exploration are not as good as expected. There is no obvious breakthrough in geological exploration in most sand-covered areas and basins. Compared with the southern section of Daxing 'anling in the east, the northern margin of North China plate has a big gap in exploration results.
As far as geological exploration in mining areas is concerned, it mainly includes the following work:
1974, the regional geological survey team of the Geological Bureau of Inner Mongolia Autonomous Region conducted a1∶ 200,000 regional geological survey in this area, and made detailed geological work on the stratum, structure, magmatic rocks and minerals in this area. 1979 submitted the regional geological survey report of Huangqiban (K-49-XV Ⅲ). Establish regional stratigraphic system, divide intrusive rocks in different periods, define the basic structural outline of the region, and delineate the prospecting area.
During the period of 1989, the first geophysical and geochemical exploration team of Inner Mongolia Autonomous Region discovered the Duren Wuliji gold mine, which is now the I ore belt of Bilihe gold mine.
From 1990 to 1992, the Fourth Institute of Geology and Mineral Exploration and Development of Inner Mongolia Autonomous Region (the Fourth Institute of Geology and Mineral Exploration) carried out geological survey in Bilihe Gold Mine 1 ore belt and its surrounding areas for three consecutive years, and the main workload completed was: core drilling 205.84m, exploratory trench 4963.48m3 and tunnel exploration/kloc.
199 1 year, the bilihe gold mine in sunite right banner was established and started mining.
1June, 1992 to1June, 1993, the former Bilihe Gold Mine hired the geological technicians of Inner Mongolia Gold Company to use the geological data of the Fourth Exploration Institute to clean up and rebuild some exploration projects of exploration trenches and adits, and completed the main workload: 1: 1000 topographic and geological survey of 0.6km2 and exploration trenches of 60km2. There are 498.6 meters of drift and vein roadway, 76 meters of shaft, 1 piece of beneficiation process test, 988 pieces of grooving sampling and basic analysis, and 60 pieces of small pieces. The first exploration report in this area was submitted, that is, the Exploration Geological Report of Bilihe Gold Mine in Sunite Right Banner, Inner Mongolia Autonomous Region (unreviewed), and I and II ore bodies were delineated in No.1 ore belt. The submitted C+D grade ore volume was 135456t, the gold metal volume was 902kg, and the average grade was 6.66× 65,438+00-.
From1May, 1995 to1April, 1998, No.4 Exploration Institute drilled 13 boreholes in Area I of the mining area, with a cumulative footage of 1587.46 meters, and completed adit exploration of 427.2 meters, with sampling analysis of 1695 boreholes. The report was approved by the Inner Mongolia Bureau of Geology and Mineral Exploration and Development of the former Ministry of Geology and Mineral Resources with the document "In-situ Exploration and Development [1998] No.220". After examination, it was agreed to accept the report. The original No.2 ore body is divided into No.2 ore body and No.3 ore body. V ore body and several small ore bodies are delineated, with ***2 1. The new gold reserves in the approval table are C+D.
From 65438 to 0999, China National Gold Group Corporation established Sunite Right Banner Jinxi Gold Mining Co., Ltd. (Jinxi Company) on the basis of the original Bilihe Gold Mine. After the establishment of the company, in view of the lack of resource reserves, the guarantee of reserve resources is regarded as the lifeline project of enterprise survival, and a large proportion of workload is invested every year. In addition to completing a lot of infrastructure work, at the same time, more than 380,000 tons of ore in the middle section above 1 180 will be upgraded to grade C. From 2000 to 2003, Jinxi Company continuously increased its prospecting efforts in the periphery of Bilihe Gold Mine. From September 2003 to the end of 2004, the ore bodies 20 1 and 202 were discovered and newly delineated in the southeast of I ore belt. Among them, the ore quantity of No.201orebody is 230 100t, the gold metal quantity is 1340kg, and the average grade is 5.82×10-6. Ore quantity of No.202 ore body11400t, gold metal quantity of 95kg, and average grade of 0.85x10-6 (summary data of mine production and exploration has not been submitted for acceptance). At present, the ore body 20 1 is the main mining object of this mine.
After two years of exploration and production prospecting in Bilihe mining area, the total amount of gold resources submitted is 3229kg, all of which are concentrated in ⅰ ore belt; Veins No.26, No.22 and No.23 with certain prospecting prospects have been discovered successively by means of ground exploration trough, shallow well and tunnel.
3. 1.3 Geological scientific research work
The geological research work in the mining area is very weak. From 2000 to 20001,entrusted by Bilihe Gold Mine, Tianjin Geological Research Institute carried out scientific research focusing on metallogenic geochemistry in Bilihe, Baiyinha and other mining areas affiliated to the company, and submitted the report "Gold Types, Geological Characteristics of Gold Mineralization and Optimization of Prospecting Targets in Zhu Rihe Area, Inner Mongolia". The report points out that there is still a certain prospecting potential in the deep and periphery of Bilihe mining area. In 2006, the author began to carry out geological research and prospecting work in Bilihe mining area, trying to determine the types of gold mineralization in this area, summarize the laws of regional gold mineralization and mineralization enrichment, and explore new resource reserves. Through systematic work, it is considered for the first time that the ore body 20 1 in Bilihe I ore belt has the geological characteristics of transition from porphyry type to epithermal deposit, and the prospecting direction of porphyry type deposits in this area is put forward for the first time. While affirming that the known No.1 ore belt and No.26 vein in the mining area have certain prospecting prospects, it is of great work value to newly discover and determine No.2 mineralized alteration belt (No.2 ore belt) in the mining area. It is suggested to optimize the exploration work, which has laid a solid foundation for the next exploration breakthrough of the deposit.