As early as last month, the colony's frontline research institute and the Starring City laboratory have jointly explored the appropriate frequency.

Through the magic wave excitation device of the magic modification, 12 seismic waves of different frequencies are continuously transmitted underground, and a "black domain" can be manufactured within a range of ten kilometers underground. In this black field, the devil can't correctly discriminate the direction, and it is impossible to distinguish the surrounding and the surface, and it will have strong physiological discomfort.

National experts in the laboratory called it an ultrasonic fence.

Twelve seismic wave excitation devices were deployed around the colony, which used the ultrasound to form a twelve-sided wall. Now, with the colony as the center and a radius of more than ten kilometers, it has become a restricted area for devils.

Thanks to this, the colonial development work that has been stagnant for a long time can finally be re-expanded.

Under the command of Captain Hong Zewei, the colonial engineering team repaired the riddled hydroponic plantations and pastures that were smashed by the devil's worms. At the same time, according to the plan of the Space Command Center, the first high-automatic steel plant was built on Mars.

There is no need for mining wells to mine iron ore at Mars.

There are iron ore on Mars.

This sentence is not a fake.

You can smell the rust smell by picking up a piece of sand from the ground.

The raw materials produced are under the soles of the feet. The newly built iron ore mine only needs to shovel the sand of one car and one car into the boiler, and then it can train a batch of finished steel. Most of the **** that has been smelted is silica, which can be used as a glass and concrete building material after a little treatment.

Part of the steel produced was used for colony construction, while the other part was made into rebar and stainless steel plates to reinforce the surface of the colony.

Yes, the steel on Mars has been cheap enough to be used as a floor tile.

The engineering team responsible for the construction will first push the steel into the ground, then fill the cement, pour it into a concrete foundation, and then lay a layer of high-strength stainless steel on the concrete floor. In this way, even if the devil's head has a long drill bit on the top of the head, don't even cut through the colony's floor.

Although there are subsonic fences, most people still feel uncomfortable when they think that the devils are excavating under the soles of their feet. Even if it is just in case, this layer of alloy flooring is absolutely necessary.

In addition, the sound insulation of concrete is very strong, which can effectively limit the ultrasonic waves to the ground, which is also beneficial to the health of colonists in the colonies.

In addition to iron ore, recently the geology brigade where Wang Qiang is located has found a considerable amount of reserves in the crater 10 kilometers away from the colony. This natural carbon mine is rare on Earth in an oxidizing environment, but it seems to be very common on Mars.

Relying on the graphite produced by this carbon mine, the colonies are now able to produce graphene independently without having to rely on imports from the city.

Both the steel plant and the graphene plant have been built, and now there are only two tasks left by the headquarters to the colony. One is the ground base station that builds the space elevator on the equator line, and the other is the 071 project.

Now, the Star Marines have established an operational base above the 071 mine. The construction team of the colony reinforces the concrete and steel for the pavement. At the same time, it also established facilities such as machine guns, communication base stations, accommodation camps, and garages.

In addition, the engineering team's drilling rig has revolved around the 071 mine, drilled a tunnel for the passing of the chariot, and reinforced concrete walls to prevent the devil's damage.

Drilling the tunnel into a five-kilometer, or even deeper, formation is a test of the construction technology of the colony's engineering team. However, they have experienced many times in this test. After more than a month of hard work, the rig has finally reached the edge of the Gaia civilization ruins under five kilometers.

What they have to do next is to continue drilling down around the ruins and drill a spiral channel. After determining the level of the Gaia civilization database, it will then dig into the remains.

"Here is team a, we have arrived at the edge of the unknown."

Following the rig, looking at the map on the holographic screen inside the helmet, Zhang Hai reported the situation to the headquarters.

"move forward."

"Received." Ended the contact with the command, Zhang Hai switched the communication to the team channel, set up the rifle in the hand, aimed at the front channel, "all combat units pay attention, the front detects a high-density vital signal, We are about to enter the danger zone. Protect the drill car, open the insurance, freely fire, and act."

The rig continued to advance, and the engineering vehicle behind it pushed the rebar into the sides and welded it, while pouring the quick-drying concrete to strengthen the tunnel. The Marines followed closely, carrying the Gauss rifle in their hands and carefully monitoring the front.

If the devil worm might come in a certain direction, then it must be right in front of the rig.

When the drill bit breaks through a rock wall, the rock in front collapses, revealing a large space. The rig stopped and the soldiers on both sides immediately approached, but there was no trace of the devil worm in the hollow layer.

Zhang Hai walked to the nearby rock wall and opened the tactical flashlight to check along the wall. He found the red-red rock and the clusters that grew on the surface of the rock.

There is no doubt that this is the oxygen supply layer.

A gesture was gestured to the soldiers behind him, and Zhang Hai carefully withdrew to the tunnel that had been reinforced. Just then, a soldier accidentally discovered a strange follicle.

The dark green follicles look like half-human height, and the oily film can see a thin layer of colorful oil spots under the illumination of the flashlight. According to some unknown rhythm, the follicles contracted slightly and swelled.

I don't know if it is stimulated by the light of the flashlight, and its agitation speed is slightly faster.

"What is this?" The rifle in the hand was aimed at the egg. The soldier reached out and pressed it on the helmet. He took a few photos and sent it to the team channel. "Report the captain, find the situation here."

"Devil worm eggs?" Looking at the image on the holographic screen, Zhang Hai frowned slightly and walked up with a rifle. "No... let the rig stop."

The drill car stopped drilling forward.

Soon, Zhang Hai reconnected with the headquarters.

As soon as the communication was connected, the headquarters asked.

"What happened? Why did the rig stop?"

"Reporting headquarters, here is team a, we drilled through a hollow formation, where we found a lot of oxygen-forming fungi, and a strange egg... probably an egg." Looking at the agitated Follicles, Zhang Hai sent those photos to the command of the expedition.

"This is the headquarters. We have received it and are sending researchers to the target area for sampling. Please wait here."

"Received." After hang up the communication, Zhang Hai gestured to the soldiers behind him and pointed to the sides of the rig.

Before the researchers arrive, they will arrange a simple line of defense here.

"What do you say about this thing?" nervously aiming at the insect and warning, Koenig whispered in the communication channel.

"I don't know, maybe it's a mutant devil? Is it a new species that we have never seen before? To be honest... even that kind of thing has been seen, even if God is standing in front of me, I won't I am surprised."

Listening to the voice of his teammates chatting in the communication channel, Zhang Hai looked at the eggs.

I saw that the egg was like a fresh heart, pulsating according to a special rhythm.

I don't know why, looking at the egg, his heart could not help but rise a strong uneasiness...