He was about to leave Seaquest for the last time. There was no chance for reflection, only an utter determination that her loss should not be in vain. Any sadness would come later.
He switched on the low-intensity interior lighting, adjusted the thermostat to 20 degrees Celsius and activated the sensor array. After checking the buoyancy and propulsion controls he extended the right-hand pincer against a switch on the door. The fluorescent lighting dimmed and water began to spray down. As the turgid liquid rose above the viewports, Jack felt the damp patch where the blood had oozed from his gunshot wound of the day before. He tried to steady his nerves.
“One small step for a man,” he muttered. “One giant step for mankind.”
When the hatch opened and the elevator raised him above the module, Jack was engulfed in darkness, a black infinity which seemed to imprison him with no hope of escape. He activated the floodlights.
The view was like nothing he had seen before. It was a world lacking all standard points of reference, one where the normal dimensions of space and shape seemed to continuously fold in on each other. The beam lit up luminous clouds of silt that swirled in all directions, slow-motion whirlpools that undulated like a multitude of miniature galaxies. He extended the manipulator arms and watched the silt separate into tendrils and streamers, shapes that soon gathered themselves together again and disappeared. In the harsh glare it seemed deathly white, like a pall of volcanic ash, the beam reflecting off particles a hundred times finer than beach sand.
Jack knew with utter certainty that he was the only living being ever to have penetrated this world. Some of the suspended sediment was biogenic, derived from diatoms and other organisms that had fallen from above, but unlike the abyssal plains of the Atlantic or the Pacific, the depths of the Black Sea lacked even microscopic life. He truly was in an underworld, a lifeless vacuum unparalleled anywhere else on earth.
For a moment it seemed as if the swirling mass would materialize as ghostly faces of long-dead mariners fated to dance a macabre jig for all eternity with the ebb and flow of the silt. Jack forced his mind to concentrate on the task at hand. The sediment was settling much faster than he had anticipated, the particles compacting with the glutinous density of mud in a tidal flat. Already it had buried the top of the command module and was creeping alarmingly up the legs of the ADSA. He had only seconds to act before it became an immovable sarcophagus on the seabed.
He engaged the buoyancy compensator and filled the reservoir on his back with air, quickly reducing the suit to neutral. As the readout turned to positive he pushed the joystick and twisted the throttle. With a lurch he moved upward, the sediment cascading past with increasing rapidity. He switched off the water jet to avoid clogging the intake and continued his ascent using buoyancy alone. For what seemed an eternity he rose through an unrelenting maelstrom. Then almost thirty metres above the wreckage he was free of it. He rose another twenty metres before neutralizing his buoyancy and angling his lights down towards the ooze that now entombed the wreckage of Seaquest.
The scene was impossible to fix to any kind of reality. It was like a satellite image of a vast tropical storm, the eddies of sediment swirling slowly like giant cyclones. He half expected to see flashes of light from electrical storms raging beneath.
He turned his attention to the sonar scanner he had activated moments before. The circular screen revealed the trench-like profile of the chasm, its features more sharply accentuated now the sensor array was clear of silt. He called up the NAVSURV program and tapped in the grid co-ordinates he had memorized for Seaquest’s final surface position and the north shore of the island. With known reference co-ordinates NAVSURV could plot present position, lay in a best-fit course and make continuous modifications as the terrain unfolded on the sonar display.
He flipped on the autopilot and watched as the computer fed data into the propulsion and buoyancy units. As the program finalized, he extracted the headset from its housing and pulled down the visor. The headset was hard-wired to the computer via a flexicord umbilical but still allowed complete freedom of movement, the visor acting as a see-through screen so he could still monitor the viewports.
He activated a control and the visor came to life. His view was filtered through a pale green lattice that changed in shape with every movement of his head. Like a pilot in a flight simulator, he was seeing a virtual-reality image of the topography around him, a three-dimensional version of the sonar display. The softly hued lines were a reassurance that he was not trapped in some eternal nightmare, that this was a finite world with boundaries that could be surmounted if his luck continued to hold.
As the water jets fired up and he began to move forward, Jack saw that the metallic joints of the arms had turned a vivid yellow. He remembered why the depths of the Black Sea were so utterly sterile. It was hydrogen sulphide, a byproduct of bacteria decomposing organic matter that flowed in with the rivers. He was mired in a vat of poison bigger than the world’s entire chemical weapons arsenal, a reeking brew that would destroy his sense of smell at the first whiff and kill him with one breath.
The ADSA had been designed to the latest specifications for chemical and biological exposure as well as extreme pressure environments. But Jack knew it was only a matter of time before sulphur corrosion ate through a joint where the metal was exposed. Even a tiny ingression would prove deadly. He felt a cold wave of certainty pass through him, a sure knowledge he was trespassing in a world where even the dead were unwanted.
After a final systems check he gripped the throttle and stared grimly into the void in front of him.
“Right,” he muttered. “Time to revisit old friends.”
Less than five minutes after emerging from the silt storm Jack had reached the western wall of the canyon. The three-dimensional lattice projected on his visor melded precisely with the contours of the rock face now visible ahead, a colossal precipice that reared four hundred metres above him. As he panned the light over the wall he saw that the rock was as stark as a freshly hewn quarry face, its surface untouched by marine growth since titanic forces had rent the sea floor a million years before.
He powered the transverse stern thruster and brought the ADSA round on a southerly course parallel to the rock face. Twenty metres below him the sediment maelstrom seemed to seethe and boil, a forbidding netherworld halfway between liquid and solid that lapped the wall of the canyon. By maintaining a constant altitude above the slope he was steadily climbing, the depth gauge registering a rise of almost a hundred metres in his first half-kilometre along the canyon wall.
As the gradient angled more sharply, a sector of the canyon floor appeared that was entirely denuded of sediment. Jack guessed it was an area where sediment had accumulated and then avalanched down the slope. He knew this was a danger zone; any disturbance could dislodge sediment further up the slope and engulf him.
The exposed sea floor was covered in a bizarre accretion, a crystalline mass stained a sickly yellow by the hydrogen sulphide that poisoned the water. He bled the buoyancy reservoir and sank down, at the same time extending a vacuum probe to sample the accretion. Moments later the results flashed up on the screen. It was sodium chloride, common salt. He was looking at fallout from the evaporation thousands of years before, at the vast bed of brine that had precipitated into the abyss when the Bosporus had sealed off the Black Sea during the Ice Age. The canyon Jack had christened the Atlantis Rift would have been a sump for the entire south-eastern sector of the sea.
As he jetted forward, the carpet of brine became patchy and gave way to a contorted landscape of shadowy shapes. It was a lava field, a jumble of frozen pirouettes where magma had welled up and solidified as it met the frigid water.