Atlantis

force that would have killed him had he not been crouched with his head in his arms. It took all his strength to keep from being thrown upwards as the hull rebounded, the surge accompanied by a horrific tearing sound. Then the wreckage settled and silence descended.

“Activate emergency lighting.”

Jack spoke to himself as he felt his body for further injury. His voice sounded strangely disembodied, its cadences absorbed by the soundproof panelling on the walls, yet it gave a measure of reality in a world that had lost all waymarkers.

As a diver Jack was used to orienting in utter darkness, and now he brought all his experience to bear. After his tumble through the hatch the missile impact had blown him past the weapons locker towards the control panels on the far side of the module. Fortunately Seaquest had come to rest upright. As he rose uncertainly to his feet he could sense the slant of the deck where the bow had ploughed into the seabed. He dropped back to his knees and felt his way across the floor, his intimate knowledge of the vessel he had helped design guiding him past the consoles that lined the interior.

He reached a fuse box in the wall to the left of the entry hatch and felt for the switch that connected the reserve battery in its protective lead housing to the main circuitry. His hand found the lever that activated the emergency lighting. Not for the first time that day he shut his eyes tight and prayed for luck.

To his relief the room was immediately bathed in fluorescent green. His eyes quickly adjusted and he turned round to survey the scene. The module was below the waterline, and the shells which had skewered Seaquest had passed through the hull above. The equipment and fixtures seemed shipshape and battened down, the module having been designed to survive precisely this kind of attack.

His first task was to disengage the module from the hull. He made his way unsteadily to the central dais. It seemed inconceivable that he had assembled the crew here for the briefing less than forty-eight hours before. He slumped heavily in the command chair and activated the control panel. The LCD monitor scrolled through a series of password requests before initiating the disengage sequence. After the third password a drawer sprang open and he took out a key which he slotted into the panel and turned clockwise. The electronic propulsion and atmosphere control systems would kick in as soon as the module was a safe distance from the wreckage.

Without Seaquest’s sensors, Jack would have no data on depth or local environment until the module was clear of the hull and had activated its own array. He guessed he had fallen into the chasm recorded by Seaquest to the north of the island, a gash ten kilometres long and half a kilometre wide that Costas had identified as a tectonic fault on the same line as the volcano. If so, he was mired in the dustbin of the south-eastern Black Sea, a collecting point for silt and a reservoir of brine from the Ice Age. With every passing minute the wreckage would be sinking further into a slurry of sediment more intractable than quicksand. Even if he managed to disengage, he might simply drive the module deeper into the ooze, entombing him with no hope of escape.

He strapped himself in and leaned back on the headrest. The computer gave him three chances to abort and each time he pressed continue. After the final sequence, a red warning triangle appeared with the word disengaging flashing in the centre. For an alarming moment the room reverted to darkness as the computer re-routed the circuitry to the internal battery pod.

A few seconds later the silence was broken by a dull staccato noise outside the casing to his left. Each muffled concussion represented a tiny explosive charge rigged to blow out the rivets in Seaquest’s hull and create an aperture large enough for the module to pass through. As the panel sheared off, the space surrounding the module filled with seawater and the bathymetric sensor came online. Jack swivelled towards the exit trajectory and braced himself as the water jets came to life, a low hum that increased in a crescendo as the engines bucked against the pivots that secured the module to the hull. A series of detonations erupted behind him as the module separated from its retaining bolts. Simultaneously the locking clamps retracted and he was thrown back violently in the seat, the compression as the saucer ejected equalling the multiple G force of a rocket launch.

The module had been designed to blast from a sinking ship beyond the suction vortex as the hull plummeted to the sea floor. Jack had experienced a simulation at IMU’s deep-water test facility off Bermuda, when the saucer came to a halt a hundred metres away. Here, the G force was followed by an equally violent jolt in the opposite direction, the module stopping only a few metres beyond the wreckage.

He had pitched his head forward in the standard safety posture and his only injuries were a series of painful welts where the straps dug into his shoulders. After taking a deep breath he unbuckled the harness and swivelled towards the workstation, his right hand pushed against the control panel to stop him sliding forward where the module had angled into the seabed.

To the left was a smaller monitor for the display of bathymetric data. As the numbers began to flicker he saw the depth gauge read a staggering 750 metres below sea level, a full hundred metres below the official maximum operating depth of the module. The base of the fault was far deeper than they had imagined, more than half a kilometre below the submerged ancient shoreline.

Jack switched on the sound navigation and ranging system and waited while the screen came to life. The active sonar transducer emitted a high-frequency narrowband pulse beam in a 360 degree vertical sweep to give a profile of the sea floor and any suspended objects up to the surface. During Seaquest’s run over the canyon two days previously they had established that the fault lay north-south, so he fixed the sonar trajectory east-west to give a cross-section of his position within the defile.

The speed of the beam meant the entire profile was visible on the monitor at once. The mottled green on either side showed where the canyon walls rose some four hundred metres apart. Near the top were jagged protrusions that narrowed the profile further still. The canyon bore all the characteristics of a horizontal tear fault, caused by plates in the earth’s crust wrenching apart rather than grinding sideways. It was a geological rarity that would have delighted Costas but was of more immediate concern to Jack because it compounded the gravity of his situation.

He realized his chances against surviving this far had been truly astronomical. If Seaquest had sunk only fifty metres west she would have impacted with the lip of the canyon, smashing him to oblivion well before the wreckage reached the sea floor far below.

He turned his attention to the base of the fault where the profiler showed a mass of light green, denoting hundreds of metres of sediment. Partway up was a horizontal line level with the apex of the sonar, a compacted layer which was the resting place for Seaquest. Above it a lighter scattering of colour denoting suspended sediment continued for at least twenty metres until the screen became clear, indicating open water.

Jack knew he was atop a drift of sediment at least as deep as the ocean above, immense quantities of silt derived from land run-off mixed with dead marine organisms, natural seabed clays, volcanic debris and brine from the Ice Age evaporation. It was continuously being added to by fallout from above and at any moment could swallow him up like quicksand. And if the quicksand did not get him, an avalanche could. The suspended silt above the wreckage was the result of a turbidity current. IMU scientists had monitored turbidity currents in the Atlantic cascading off the continental shelf at 100 kilometres an hour, carving out submarine canyons and depositing millions of tons of silt. Like snow avalanches, the shock wave from one could trigger another. If he was caught anywhere near an underwater displacement of such magnitude he would be doomed without hope of reprieve.

Even before he tried the engines he knew it was a forlorn hope. The erratic hum as he powered up the unit only confirmed that the water jets were clogged with silt and incapable of shifting the module from the grave it had dug itself. There was no way the IMU engineers could have anticipated that the first deployment of their brainchild would be under twenty metres of ooze at the bottom of an uncharted abyss.

His one remaining option was a double-lock chamber behind him that allowed divers to enter and exit. The casing above was enveloped in a swirling cloud of sediment which might still be sufficiently fluid for escape, though with each passing minute the chances were diminishing as more of the particulate matter came out of solution and buried the module ever deeper in a mass of compacted sediment.

After a final glance at the sonar profile to memorize its features, he made his way to the double-lock chamber. The retaining wheel turned easily and he stepped inside. There were two compartments, each little larger than a closet, the first an equipment storage and kitting-up room and the second the double-lock chamber itself. He pushed his way past a rack of E-suits and trimix regulators until he stood before a metallic monster that looked like something from a science-fiction B movie.