Secular scientists refuse to accept a global flood on Earth, where oceans currently take up three-quarters of the planets surface area. Yet, ironically, many are ready to believe in large-scale flooding on Mars, whose surface is (now, at least) bone-dry nor is there any firm evidence of subsurface liquid water!
Below is a sampling of quotations showing scientists readiness to accept huge flows of water in the Martian past.
In stark contrast to the present environment, however, numerous landforms provide signs, or indicators, of extensive past activity of water and ice on the martian surface. . . . The martian outflow channels are immense . . ., as much as 150 km wide and 2,000 km in length. . . . Although a variety of other fluid-flow systems have been invoked to explain these features, the whole assemblage of these landforms is best explained by cataclysmic flood processes, with particular analogy to the origin of the Channeled Scabland [in the Pacific Northwest]. . . . The sizes of martian outflow channels imply immense discharges of water, exceeding any known flood flows on Earth. . . . The calculated peak-flow magnitudes are comparable to those of the high-discharge western boundary currents of the Earths world ocean, such as the Gulf Stream, the Kuroshio and the Agulhas (Victor R. Baker. 2001 [Jul 12]. Water and the martian landscape. Nature, Vol. 412, pp. 228-236).
[Matthew] Golombek [of the Jet Propulsion Laboratory] and his colleagues believe that the first [Mars Pathfinder] images confirm their suspicion that billions of years ago a great flood of a billion cubic meters per second swept the region [within the Ares Vallis plain] for weeks, carrying a variety of rocks from distant highlands (Richard A. Kerr. 1997 [Jul 11]. Pathfinder Strikes a Rocky Bonanza. Science, Vol. 277, pp. 173f.).
Images of Mars . . . reveal enormous outflow channels etched on the surface. Some of these structures are more than 200 kilometers wide and can stretch for 2,000 kilometers or more. These channels emanate from what is called chaotic terrain, regions of fractured, jumbled rocks that apparently collapsed when groundwater suddenly surged outward. The ensuing floods carved the vast channels, leaving streamlined islands more than 100 kilometers long and gouging cavernous potholes several hundred meters deep. [Victor R.] Baker [of the University of Arizona] compared the Martian outflow channels to similar, albeit smaller, flood features found on Earth in parts of Oregon and Washington State. Those so-called channeled scablands of the Pacific Northwest formed after a glacier that had dammed a large lake broke open suddenly and caused a catastrophic flood.
The geometry of the Martian outflow channels indicates that water could have flowed along the surface as rapidly as 75 meters per second (170 miles per hour). Michael H. Carr of the U.S. Geological Survey estimates that the vast quantity of water necessary to create these many enormous channels would have been enough to fill a global Martian ocean that was 500 meters deep, although not all this liquid flowed at one time (Jeffrey S. Kargel and Robert G. Strom. 1996 [Nov]. Global Climatic Change on Mars. Scientific American, Vol. 275 No. 5, pp. 80-88).
The martian surface shows large outflow channels, widely accepted as having been formed by gigantic floods that could have occurred under climatic conditions like those seen today. . . . Images acquired by the Mars Orbiter Camera (MOC) during the aerobraking phase (September 1997 to February 1998) of the Mars Global Surveyor mission typically have resolutions in the range 48 m per pixel, in most cases a factor of 2050 times better than previous imaging. The images reveal new details about the valleys that strongly support an origin by fluid erosion (Michael C. Malin and Michael H. Carr. 1999 [Feb 18]. Groundwater formation of martian valleys. Nature, Vol. 397, pp. 589-591).