North.'
Challenger shook, then dipped and rolled.
'Seismic seawave,' Ilse shouted. 'Assess an avalanche on North.' Jeffrey had the glimmer of an idea. If they could somehow predict one of these outbursts, and get into proper position, they might use the noise to get a sonar contact off Deutschland. Of course, this could backfire and give Challenger away, and Eberhard might get in the first and fatal shots. Or, the outburst might not behave as expected and itself deal Challenger the lethal blow. But with his own port-side wide-aperture array in bad shape, and some of his other sonars wrecked completely, Jeffrey knew he had no choice; time was on Eberhard's side.
Jeffrey told COB to activate all ship's passive photonics sensors, and window the pictures onto one of the vertical wide-screen displays. So far there was just darkness.
'Oceanographer.'
'Captain?'
'Let's check out the west flank of Middle from closer range.'
'Sir? There was just a magma outburst there.' 'Let's go take a look.'
'Magma outburst!' Haffner shouted. 'South flank of volcano North!' Deutschland shook, then dipped and rolled.
'Seismic seawave,' Beck shouted. 'Assess an avalanche on North!'
'Any contact on Challenger?'
'Working, Captain. Holography needs time to exploit the acoustic illumination…. No object identified as Challenger.'
'He may be hugging terrain, trying to use shadow masking.'
'Recommend we gain some altitude for a better look-down aspect angle.' In a strange way Beck was enjoying himself now. This was a pure contest of will and technology between Challenger and Deutschland, and he could focus solely on survival and success with a clear conscience. Let them sink Fuller's ship, here in this ecological wasteland, and help speed the larger war toward victory
'Concur, Einzvo,' Eberhard said. 'Pilot, decrease depth. Keep us three hundred meters off the bottom. Maintain search pattern within volcano field. We'll find him. We have sonar superiority, and he's outgunned.'
Challenger cruised the west side of the central volcano. The ship moved at three knots, taking careful measurements. Jeffrey ordered the sonar speakers turned off altogether, because of the noise; Ilse used her headphones, with the volume set well down. Even at dead slow, the ship shook and jostled as it had when she'd made flank speed before. The volcano field was never still, and the shocks transmitted through the water never ceased. Ilse wondered when something on Challenger would break.
Jeffrey ordered Meltzer closer to the bottom, despite the risk of a crash into terrain. They needed better data, if Ilse was to have a hope of forecasting how these magma outbursts behaved.
On passive photonics, with the gain at a factor of one hundred thousand, she began to see something. The scientist in her was fascinated. The common sense in her said this was madness — volcanologists on dry land had been killed getting too close to their subject of study….
Ilse stared at the screens. Lava poured from a side vent in Middle's cone. It glowed bright orange, before quickly quenching to red, then turning dark as it cooled more. There was no steam as the molten rock emerged and hit the seawater; the pressure at eleven thousand feet was much too great.
The lava was alive. As Ilse watched, it cascaded and spattered. The lava's surface hardened quickly in the cold, often forming a glassy, brittle shell, only to shatter as more glowing rock, at 3,000° Fahrenheit, forced its way from inside. The lava formed strange shapes, some resembling huge cow patties, others extruded toothpaste. The glowing lava gave its own illumination. The imagery rippled from the heat. Ilse saw large pillow lavas. One resembled a cracked egg: the hardened surface broke, and the liquid rock inside poured out and hardened like a yolk.
Challenger neared another active vent, and the picture grew brighter. Here lava emerged with greater force. Ilse watched red chunks and cinders erupt and cascade like fireworks in slow motion. Challenger trembled constantly, from immense geological forces transmitted through the water.
On her headphones, Ilse listened to the accompanying sounds. The lava rumbled as it upwelled through faults and dikes, then gurgled as it flowed through tubes and fumaroles. As new hot lava forced the cool — young rock ahead of it downhill, the advancing front made a crunching, scraping, clinking noise.
'Oceanographer. Recommendations?' Jeffrey's voice pulled Ilse from her reverie.
'Er, to predict large-scale behavior we need to examine more of this face. Build a recent history of the cone flank.' 'What do you think, XO?'
'If we want to regain contact with Deutschland, sir, it is better to linger in one area. If both of us keep moving, the chances are great we'll both just go in circles and keep missing each other.'
'Captain,' Kathy said. 'Ilse and I discussed something earlier. In this acoustic sea state, low-frequency look- down pings are unlikely to be detected by an adversary. Properly tuned sound energy will penetrate the seafloor, and give us valuable geologic information.'
Jeffrey turned to Ilse. 'This isn't a scientific research expedition, you know.'
'Sir, we need that kind of data to time the seismic events. If you want to use that tactically against Deutschland…'
'Very well. Go active at your discretion with ground-penetrating sonar.'
'Captain,' Ilse said, looking up from her console a few minutes later, 'recommend switching photonics to active laser line scan.'
'That's risky,' Jeffrey said.
'Understood. But we're too far from hot lava to gain illumination now. Line scan will provide the fine- resolution data I've got to have.'
'Chief of the Watch, activate all look-down laser line-scan cameras.' COB acknowledged.
As Challenger moved along, Ilse studied her screens. The terrain here was a jumble of layers made at different times. Ilse built a picture of how and when each lava flow had formed, their origins and sequencing. She saw large and squared-off blocks, with light and darker swirls and marbling, where molten basalt had thickened in alternating bands as its mineral content varied; this gave further clues about the Middle cone's behavior. These blocks were blown out from the central crater in some giant explosion, or they'd fallen from the rim in a violent avalanche. Either way, their sparkling, crinkled surfaces suggested they were very recent. Ilse realized the next outburst would probably produce more such huge projectiles, and one might come smashing through Challenger's hull. Kathy's people continued gathering ground-penetrating data, and passed it to Ilse. From density variations below the floor, Ilse was constructing a map of the active magma chambers, their sources in the earth's mantle, and their vents into the sea. Using Doppler she could actually follow how the magma moved, when it did move.
'What do you want to examine next, Oceanographer?' Jeffrey asked.
'The large subsidence that's just west of Middle, at the bottom of the slope.' Jeffrey gave the helm orders.
Jeffrey watched the photonics intently. Challenger moved over a wide bowl in the seafloor, a lava lake whose surface had hardened before the underlying lava drained away, back into some crack or chasm. The lake roof then collapsed, except for isolated pillars jutting from the floor. As Challenger passed the far wall of the bowl, Jeffrey saw where lava had emerged and cooled in stages, forming distinct layers, their broken edges now exposed. At Ilse's request, Jeffrey ordered Meltzer to make another pass over the bowl, from a different direction, so she could grab more data. When Challenger reached the center of the lake, the ship trembled strangely.
'Subsurface noise increasing rapidly!' Kathy said. 'Assess as new outflow onto the lake floor. Advise clear datum smartly!'
Jeffrey snapped helm orders.
It was too late. While Jeffrey watched, lava burst from several fissures in the lake bed. The bowl began to fill. The lava glowed bright red. The ship was struck by thermal updrafts. Lava hardened, then cracked and flowed again. Challenger bucked and buffeted; heated water gave less buoyancy.
'Make turns for fifteen knots!'
Meltzer acknowledged as he fought the turbulence. Jeffrey watched his screens, horrified, as more and more lava poured up into the lake. It sloshed and rippled now, like water splashing in a bathtub. Challenger began to
