Domain: Natural Science — Geology & Geophysics
Target concept: Permeability of Water Through Sandstone Blocks Compared to Tight Rocks

Video generation prompt: Place a sandy sandstone and a smooth, dense rock side by side on a tray, then pour equal amounts of water onto their top surfaces simultaneously.

Evaluation guide:
(i) Target concept: Permeability contrast arising from pore structure differences between clastic sedimentary rock (sandstone) and crystalline/metamorphic tight rock.
Minimum mechanism: Sandstone must possess macroscopically visible intergranular porosity enabling capillary-driven infiltration; dense rock must possess negligible connected porosity preventing bulk fluid entry; both conditions must hold for observed wetting contrast to emerge.
(ii)Storyline: [Frame 0–2] Stable wide shot: tray centered, two rocks placed adjacent, dry, fully visible, no motion. [Frame 3–5] Water streams initiate synchronously from identical height onto top surfaces; streams maintain parallel trajectory. [Frame 6–8] Immediate divergence: sandstone surface darkens progressively downward; dense rock surface remains light with pooled water. [Frame 9–10] Contrast sustained: no recovery, no mixing, no secondary effects. Perspective: fixed frontal view, full-rock visibility maintained, no occlusion, consistent lighting.

Manual:
Experimental Procedure
1. Place a sandy sandstone block and a smooth, dense rock side-by-side on a flat tray.
2. Simultaneously pour equal amounts of clear water onto the top surface of each rock.
Observation of Experimental Phenomena
Water rapidly darkens and soaks into the sandstone, showing visible downward seepage. Water pools or beads on the dense rock surface with little to no darkening below the top layer.
Summary of Experimental Principles
Sandstone has high permeability due to interconnected pore spaces between sand grains; tight rocks (e.g., granite, basalt) have low permeability due to minimal pore space and poor connectivity.

Prompt Grounding rubric:
level_1: No tray is shown; or no sandstone block appears; or no smooth, dense rock appears; or no water is poured onto either rock; or the two rocks are not placed side by side; or the objects shown don't match the prompt (e.g., a clay lump stands in for the sandstone, or a glass block stands in for the dense rock).
level_2: A tray and two rock-like objects appear, but at least one is the wrong type (e.g., both look like granite, or one is a loose pile of soil rather than a rock); or water is poured but not onto both rocks at essentially the same moment; or the rocks are stacked or overlapping instead of side by side; or water lands on only one of the two rocks.
level_3: A tray holds two distinct rock-like objects side by side, one visibly grainy and rough (the sandstone), the other visibly smooth and dense; roughly equal streams of water are poured onto the top of each rock, starting at about the same visible moment; no other major departure from the setup is present.
level_4: Everything described for score 3 holds, and beyond that: the sandstone's surface clearly shows individual grains or a sandy texture; the dense rock's surface is uniform with no visible pores, cracks, or graininess; the water lands on the top face of each rock rather than the side or edge; both pours begin and end within one continuous camera take, without pausing or repositioning.
level_5: Everything described for score 4 holds, and beyond that: the sandstone and dense rock are distinguishable both by texture (grainy vs. smooth) and by color (e.g., a light tan sandstone against a dark gray basalt or gabbro); the two water streams look equal in height, width, and duration; both rocks stay put on the tray for the whole video; no hands, labels, or on-screen graphics appear anywhere in the frame.

Scientific and Causal Correctness rubric:
level_1: No visible difference in how the two rocks respond to the water; or water soaks into both the sandstone and the dense rock at the same rate; or water pools the same way on both surfaces; or the dense rock absorbs water as quickly and visibly as the sandstone does.
level_2: A difference appears but runs backwards: the sandstone shows no absorption at all while the dense rock darkens deeply and quickly, or water visibly soaks into the dense rock faster than into the sandstone.
level_3: The two rocks clearly respond differently: the sandstone darkens and/or shows water visibly moving downward into it, while the dense rock instead shows the water pooling, beading, or spreading sideways across the surface without darkening, though the timing or extent of the difference may still be a little unclear.
level_4: Everything described for score 3 holds, and beyond that: the sandstone keeps darkening progressively downward from the top for as long as water is applied and afterward; the dense rock shows no downward darkening at all, only surface-level wetness or a standing pool; this contrast holds for at least about 70% of the visible time after the pour, with no reversal such as the dense rock suddenly darkening deeply after a delay.
level_5: Everything described for score 4 holds, and beyond that: the sandstone's darkening starts while the water is still being poured and keeps advancing downward without pausing; the dense rock's surface below the very top stays uniformly light with no hint of subsurface darkening; the water sitting on the dense rock holds together as a pool or sheet rather than breaking apart or vanishing early; nothing else in the shot (splashing, fogging, evaporation) creates a false impression of darkening.

Spatiotemporal Consistency rubric:
level_1: Severe breaks in continuity: one or both rocks jump to a different position or vanish and reappear between frames; the tray disappears partway through and comes back; the water stream snaps from one shape or position to another with no continuous path in between; the overall lighting suddenly flips, such as a bright scene going dark within a single frame; the camera cuts or zooms mid-pour; a rock's shape breaks apart for no reason connected to the pouring.
level_2: Clear but less severe glitches: a rock's position changes noticeably between the start and end of the pour; the water stream starts or stops abruptly rather than tapering off naturally; the tray tilts or wobbles for no reason; the direction of the shadows on the rocks changes partway through the video; background objects flicker or momentarily change shape.
level_3: Small but noticeable flaws may be present (such as a brief, barely-visible shift in a rock's position, or a short flicker in the water stream lasting no more than a couple of frames), but there is no teleporting, no camera cuts, no structural breakage, and no sudden lighting jump.
level_4: Everything described for score 3 holds, and beyond that: both rocks stay in the same relative position and orientation the whole time; each water stream keeps a steady thickness and path from where it leaves its source to where it hits the rock; the tray's surface shows a steady, consistent reflection; no part of the image tears, warps, or ghosts between frames.
level_5: Everything described for score 4 holds, and beyond that: neither rock, the tray, nor either water-impact point drifts at all across the video; the water streams show natural speeding up and slowing down and flow like a cohesive liquid rather than a rigid rod; the direction, brightness, and softness of the lighting and shadows stay the same throughout; the video shows no flicker, no aliasing artifacts, and no inconsistency in motion blur.