Geological characteristics and prospecting indicators of molybdenum-nickel deposits

Second, the geological characteristics of the mining area

Stratum

The Upper Sinian and Lower Cambrian are exposed in the mining area. There is a nickel-molybdenum multi-element mineralization layer in the black rock series at the bottom of the Lower Cambrian Niutitang Formation. This layer is the target layer for molybdenum ore prospecting.

(1) Sinian system lighting group ()

The lithology is dominated by gray-white dolomite , and the joints are more developed. The bottom is a thin layer of broken argillaceous dolomite, the lower part is a braided, pseudo-deciduous dolomite, the middle is a gravel dolomite, the upper part is gray-white medium-thick layer, the middle is a coarse-grained crystal from the cloud rock, and the top is a siliceous white cloud. rock; dolomite can be seen in a top surface of the angle between the micro-erosion potholes and dolomite overlying unconformity phosphate rock and overburden overlap phenomenon, the lens body can be seen partially limonite ore. It is 320 to 400 meters thick.

(2) The Cambrian Department of the Cambrian Department ()

1 ore layer (), 2 to 6 meters thick.

a. Phosphorus rock layer: light gray to black, thin layer or block structure, hard and brittle, localized dolomite lens. The mineral composition is mainly colloidal phosphate, followed by mud, siliceous and dolomite. It is lenticularly distributed and has a localized pinch phenomenon. It is in false integration with the underlying lamp group.

b. scaly black shale: scaly structure, soft and easy to form scales, layering is not developed, scales are bright black, loose and easy to form powder, rich in phosphorus siliceous, pyrite and other tuberculosis and sulphides strip, thickness of 1 to 10 cm, generally L ~ 3 cm, they have only one layer, partially visible 2 to 3 layers, discontinuous distribution, extremely discontinuous. The main component of the rock is hydromica , followed by carbon, organic and pyrite. The thin layer of siliceous rock is locally sandwiched, which is the main aluminum deposit.

c. Sheet-like carbonaceous shale with thin plate-like carbonaceous shale lens.

d. scaly high carbon shale.

2 black sheet flaky carbon shale (): intercalated siliceous mass and siliceous silty shale, after weathering, is book-like, thick 3.28 ~ 6.00 meters.

3 black platy carbon shale (): medium-thick layered, siliceous tuberculosis contains more pyrite and sponge bone fossils, spherical after detachment, thickness 8.0 ~ 10.0 meters.

4 black thin-layered plate-like gray shale (): its composition is mainly muddy, gray matter, carbonaceous followed by micro-layered structure, gray-white after weathering, 14 to 18 meters thick.

(3) Cambrian Department of the Department of the Department of Health ()

The lower part is gray, gray-yellow hydromica shale, muddy structure, containing muscovite and calcareous tuberculosis, the page is not developed, joint development, the lower part is light gray dolomitic shale strip; after weathering, it is yellow fragment. It is about 70 to 120 meters thick.

The upper part is calcareous shale, grayish green, and its composition is mainly muddy, containing muscovite, often with calcium tuberculosis and calcareous lens body. Its lens body is 0.5 to 3 meters thick and becomes ellipsoidal after weathering. It is about 50 to 70 meters thick.

(4) The Cambrian Department of the Qingxue Cave Group ()

The lower section is gray thin-middle layer argillaceous limestone, medium-thick layer limestone, 116 meters thick; the middle section is potassium-bearing shale (dolomite, calcareous shale), containing 5.17%-6.49%, 26 meters thick; Limestone and dolomite, 117 meters thick.

(5) Quaternary (Q)

It is composed of alluvial layers and residual slopes, consisting of debris formed by weathering of the above-mentioned bedrocks, sand and gravel, etc., and is 0-20 m thick.

2. Construction

The mining area is located in the south wing of the second-order slanting direction of the northeast tipping slope of Guzhang anticline. The structure is simple and simple. It is a monoclinic layer with a northward slope, and the production is gentle, and the inclination angle is generally 10°-15°. In the southern part of the mining area, the fault structure is relatively developed, mainly including the F5 in the NW direction, the F2 in the north-north direction, and the F6 in the NE direction.

(1) F5 normal fault

It is distributed near Huangjiashed (north side), with a trend of 280° or so, tending to the northeast, with a dip angle of about 60°, an extension of more than 800 meters, a vertical fracture of about 40 meters, a lower plate, and a charcoal shale of the Niutitang Formation. The Dengying Formation of the Dengying Formation is in contact with faults, which destroys the integrity of the ore layer and has a certain impact on the ore layer.

(2) F2 reverse fault

It is distributed near Huangjiashed (east side), with a strike of about 10°, a tendency to the west, an extension of more than 1,500 meters, a break of 30 to 50 meters, cutting F5 and Sinian and Cambrian, resulting in discontinuity of the ore. .

(3) F6 normal fault

Seen on the south-south side of Pengjiagang, the fault strikes about 70°, and the fault distance is small, which partially affects the continuity of the ore layer.

3. Magma rock

There is no magmatic rock mass in the area, and there is slight hydrothermal activity.

Third, the geological characteristics of the ore body

1. Ore body characteristics

In the mining area, molybdenum, nickel, vanadium , phosphorus and other minerals are present at the bottom of the Cambrian Niutitang Formation. Phosphorus-bearing dolomite is distributed in the upper part of the Sinian, and the phosphorus-rich lump lens is partially integrated.

The ore-bearing layer is composed of scaly black shale and sheet-like carbonaceous shale. It is controlled by engineering and has ore body distribution. The thickness and grade change are small, relatively stable and continuous, and it has a layered distribution. According to the work results: the thickness of the ore layer is 0.19~1.42 meters, with an average of 0.442 meters, the key grade is 0.05%~0.868%, the average is 0.46%, the nickel grade is 0.012%~0.977%, the average is 0.336%, the grade is 0.088%~0.328%, the average is 0.208. %

2. Ore type

The following five types of ore are known.

1 Phosphorus-type nickel and molybdenum-poor ore: light gray-黝 black, thin plate-like, dense block-like, intertwined tuberculous, vein-like cryptocrystalline structure, from phosphate rock (60% to 65%), Fluorite apatite and carbon apatite (5% to 10%), quartz , calcite, etc. (30%). The ore contains Ni0.017%～1.812%, with an average of 0.17%, containing Mo0.01%～1.396%, with an average of 0.147%, containing 8.57%～39.54%, with an average of 24.51%.

2 Limonite: soil-like loose, porous structure, muddy-gel-like structure, mainly composed of limonite, followed by hematite, apatite, nickel Hua, molybdenum, etc. It is a cyst or chicken nest that is not continuously distributed in the oxidation zone and belongs to the secondary leaching ore. The total iron content of the ore is about 28.83%, containing less than 0.1% of Ni, and containing 0.1% to 0.73% of Mo.

3 Metal sulfide ore rich in nickel and molybdenum: lead gray, grayish yellow, strip or thin plate, lenticular, intermittently distributed between phosphorite and scaly black shale, metal minerals are mostly glued The granules are embedded in each other, consisting of nickel sulphide minerals (5% to 15%) of molybdenum aggregates (15% to 25%), colloidal pyrite (35% to 40%) and phosphorus-silica shale (40). The composition of this kind of ore is unstable and varies greatly, but the content of Ni and Mo is more than 1%, and the highest contains 4.38% of Ni and 9.30% of Mo. It is the only ore in the ore section. (Note: Nickel sulfide minerals are a general term for several nickel minerals and are susceptible to weathering loss.)

4 scale-like nickel-molybdenum ore: black, scaly or sheet-like structure, shale structure, containing siliceous, phosphorous and other tuberculous and silty lens bodies, ore from 2% to 3% nickel sulfide minerals, 2% ~ 5% molybdenum aggregate mineral, 8% to 10% pyrite, 80% to 85% charcoal plus quartz. The content of Ni and Mo is generally above 0.1%, and the ore change is relatively stable compared with other ore types, and it is the main ore of the ore section.

5 plate-shaped nickel-containing aluminum ore: black, plate-like structure, shale structure, from 85% to 90% charcoal, less than 1% nickel sulfide mineral, about 1% key assembly and 7% to 10% yellow iron Mine composition. The nickel-molybdenum content changes greatly, and some nickel- platinum content can meet the industrial requirements, which is the secondary ore in the mine section.

3. Mineral composition

1 Nickel minerals: The main nickel sulfides are disulfide nickel ore, pyrite nickel ore, purple sulfur nickel iron ore, arsenic nickel ore, mostly granular, irregular granular, short veins, formed together with colloidal pyrite. "Nickel aggregate", which is mainly a highly integrated layered or meager sandwich (ie, metal sulfide layer), followed by a ring-like band around a phosphor sheet-silicone-sludge structure, which forms a shell of tuberculosis .

In addition, there are two kinds of epigenetic minerals, nickel vanadium and vanadium, which are light blue-green, often needle-like and granular, and easily soluble in water.

2 Aluminum minerals: Most of them are “key assemblies”, and molybdenum is mainly present in amorphous or cryptocrystalline state. The molybdenum aggregate is irregularly block-shaped and lenticular in the ore layer, and a small amount of veins are closely symbiotic with colloidal pyrite and nickel minerals, forming a base of other minerals, generally having a particle size of 0.1 to 2.5 mm.

3 pyrite: the vast majority of the formation of granular aggregates or tuberculosis, the general particle size of 0.01 ~ 0.5 mm; colloidal and nickel key closely symbiotic, generally containing other metal elements. It contains Ni 0.17% to 1.02%, Mo 0.5% to 1.60%, and V 0.01%.

Also, see a small amount limonite, hematite, tennantite copper ore, chalcopyrite, covellite, sphalerite, cinnabar, water amblygonite (uranium).

4. Associated beneficial components

In addition to the main elements of molybdenum and nickel, the deposit also contains platinum, plutonium, tantalum, niobium, tantalum, memory, silver , selenium , vanadium, etc. for comprehensive recycling.

Fourth, the genesis of mineral deposits and prospecting signs

1. The cause of the deposit

The nickel-molybdenum deposit in the Datun mining area is mainly produced at the bottom of the black clay facies of the Cambrian Niutitang Formation. From the analysis of paleogeographic environment, it can be said that the area is located at the edge of the shallow sea shelf. In the black clay facies, a large amount of colloidal pyrite and phosphorus nodules, as well as various organic substances, are often observed, and at the same time, rich metal elements such as Ni, Mo, V, P, etc. are found by spectroscopic and chemical analysis. U, Cu, Pb, Zn, As, Sb, Ti, Zr, Se rare earth and platinum group elements. According to the current work in the northwestern part of Hunan, the content of elements in some areas is somewhat different. In addition to the main elements such as Ni, Mo, V, P, U, etc. in the nickel ore deposit in Dayu mining area, La, Ce, Y in rare earth elements Pt, Pd, Os in the platinum group element and Se in the rare element and the precious metal Ag have a certain content.

In the identification of rock ore, it is found that Ni is usually cohesive with colloidal pyrite in a colloidal or irregular granular form (60% to 70% of the total nickel). Mo is uniformly mixed with a carbonaceous and clay type substance in a MoS state to form a "molybdenum aggregate". A mixture of a molybdenum aggregate and a colloidal structure, FeS, is often seen in the ore layer. Sometimes it surrounds the edge of the phosphorus-silica tuberculosis and forms the outer shell of the tuberculosis. According to the characteristics that Ni and Mo elements are mainly enriched in clay facies in the form of colloidal particles, and the layers are stable and layered, it indicates that their migration and occurrence are carried out as clay particles adsorbed in the clay material. When these elements encounter a suitable chemical environment during migration, they are deposited with the clay material in the black shale phase, enriched to form deposits with certain industrial value.

2. Prospecting mark

(1) The molybdenum ore body in the lower part of the black rock series of the Lower Hanjiangtang Formation of the Cambrian in northwestern Hunan has a certain metallogenic period and a stable and regional metallogenic horizon and corresponding metallogenic part. The Niutitang Formation is molybdenum. The geological premise of mine prospecting.

Automatic Motorcycle

Automatic Motorcycle,Automatic Electric Motorcycle,Automatic Adult Motorcycles,Fully Automatic Motorcycles

ZETHS Vehicle Technology Co.,Ltd , https://www.zethscn.com