Structural Alteration Mineral 3D Mapping And The Prospecting Prediction In East Of Linglong Gold Orefield,Jiaodong,China

Jiaodong gold ore concentrated area is an important gold production base in China, and the eastern part of Linglong ore field in it has been the main production area of Shandong Gold Mining(Linglong) Co., Ltd. in recent years. This area is likely to be the next decade’s resource potential and prospective area of concealed deposits, so the research of this area is of great importance. Since the three-grade reserves of the main producing mines imbalances, lack of replacing resources has become an urgent problem currently. The eastern part of Linglong Gold Deposit is also facing difficulties of insufficient reserves, and research here has always been relatively weak, coupled with the complex ore-controlling structure and many concealed mineral deposits, thus, the research is both challenging and meaningful.By carrying out the field survey of deposits No. 48 and 50 and analyzing the geochemical data of 786 samples, the paper describes the geophysical and geochemical characteristics of the structural alteration zone at the study area, and completes structural alteration facies mapping; by measuring the 1 typical profile on the surface and 4 typical profiles in downhole, a structural alteration zone profile is drawn; based on the above work, and according to the three-dimensional distribution of the second enrichment zone, three-dimensional distribution model of the structural alteration metallogenic system at eastern deposit of Linglong gold deposit is established. The main achievements are as follows:1. Linglong gold ore field is a typical quartz vein type gold deposits formed mainly by hydrothermal filling and controlled by NEE-NE compressional torsional fractures, the orebody near surface is mainly quartz vein type, and orebody in the mid-deep and deep places are quartz vein type combined with altered rock transitional type,and the deep ore types are mainly altered rock type, secondary quartz veins, and with the thickening of the veins, the grade decreases linearly.2. Veins extend mostly "Y" shaped intersection to the deep, and the intersection part provides space for the enrichment of gold minerals, gold-bearing hydrothermal repeats precipitation and enriches to higher grade. The alteration of veins is nearly symmetric distributed with the main vein as the core, and with the alteration intensity gradually weakening from the inside to the outside, the gold contents decrease.3. Alteration zone of Linglong ore field shows the characteristics of gradual transition from quartz vein type to altered rock type, sizes gradually strengthen from the west to the east, from the north to the south, and deposits occur primarily in structural alteration belt.4. Based on three-dimensional measurements of structural alteration phase, and combined with previous geological data and the alteration zone distribution rules, deep yet not closed ore body are forecast, and 48 and 50 veins are considered to be with resource prospects. According to drilling engineering system control, deep or deeper part of Linglong gold field has huge prospecting potential and has achieved good effects.