Features include information on tides, currents and winds.

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In addition to high-definition content for 12, 000 U.S. lakes, the Magellan eXplorist 510 Marine Edition includes U.S. coastal coverage up to two miles offshore, with data on 5-foot contours, tides, currents, wrecks, port plans, marsh areas, and marine services.

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There are big tides around Jersey, strong currents and unpredictable winds.

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Although the first signs of a significant find came eight months ago, exploring the area has been extremely difficult because the remains lie in highly treacherous waters, with strong currents and rip tides.

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If local gravity differences are not pulling water about to create these features, then other factors such as currents, winds and tides must be responsible.

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