Consider the following statements made about the sedimentary rocks: 1. Sedimentary rocks are formed at Earth's surface by the hydrological system. 2. The formation of sedimentary rocks involves the weathering of pre-existing rocks. 3. Sedimentary rocks contain fossils. 4. Sedimentary rocks typically occur in layers. Which of these statements are correct?

1. Statement 1 is correct: Sedimentary rocks are formed from the accumulation and cementation of sediments at the Earth's surface and within bodies of water, processes heavily influenced by the hydrological system (water, ice, wind). 2. Statement 2 is correct: The formation process begins with the weathering (physical and chemical breakdown) of pre-existing rocks (igneous, metamorphic, or older sedimentary rocks) to produce sediment. 3. Statement 3 is correct: Since sedimentary rocks form at relatively low temperatures and pressures from accumulated sediments, they can preserve the remains of organisms, resulting in fossils. 4. Statement 4 is correct: Sediments typically accumulate in horizontal layers or strata, leading to the characteristic layered appearance of sedimentary rocks. Therefore, all four statements are correct.