"Flat" Geodes

I'm trying to get a feature using the geode type, but I want it to be longer in the x/z plane compared to the y plane -- any ideas on how to accomplish this?
Here's where I'm at right now, as simple as possible with just some debug materials to be able to see
{
    "type": "minecraft:geode",
    "config": {
        "blocks": {
            "cannot_replace": "#minecraft:features_cannot_replace",
            "invalid_blocks": "#minecraft:geode_invalid_blocks",
            "filling_provider": {
                "type": "minecraft:simple_state_provider",
                "state": {
                    "Name": "minecraft:purple_concrete"
                }
            },
            "inner_layer_provider": {
                "type": "minecraft:simple_state_provider",
                "state": {
                    "Name": "minecraft:air"
                }
            },
            "alternate_inner_layer_provider": {
                "type": "minecraft:simple_state_provider",
                "state": {
                    "Name": "minecraft:air"
                }
            },
            "middle_layer_provider": {
                "type": "minecraft:simple_state_provider",
                "state": {
                    "Name": "minecraft:air"
                }
            },
            "outer_layer_provider": {
                "type": "minecraft:simple_state_provider",
                "state": {
                    "Name": "minecraft:air"
                }
            },
            "inner_placements": [
                {
                    "Name": "minecraft:air"
                }
            ]
        },
        "layers": {
            "filling": 1.7,
            "inner_layer": 2.2,
            "middle_layer": 3.2,
            "outer_layer": 4.2
        },
        "crack": {
            "base_crack_size": 0,
            "crack_point_offset": 0,
            "generate_crack_chance": 0
        },
        "noise_multiplier": 0.05,
        "invalid_blocks_threshold": 1,
        "distribution_points": 2
    }
}