Evidence for ice ages
Geological evidence for ice ages comes in various forms, including rock scouring and scratching, glacial moraines, drumlins, valley cutting, and the deposition of till or tillites and glacial erratics. Successive glaciations tend to distort and erase the geological evidence, making it difficult to interpret. Furthermore, this evidence was difficult to date exactly; early theories assumed that the glacials were short compared to the long interglacials. The advent of sediment and ice cores revealed the true situation: glacials are long, interglacials short. It took some time for the current theory to be worked out.
The chemical evidence mainly consists of variations in the ratios of isotopes in fossils present in sediments and sedimentary rocks and ocean sediment cores. For the most recent glacial periods ice cores provide climate proxies from their ice, and atmospheric samples from included bubbles of air. Because water containing heavier isotopes has a higher heat of evaporation, its proportion decreases with colder conditions. This allows a temperature record to be constructed. However, this evidence can be confounded by other factors recorded by isotope ratios.
The paleontological evidence consists of changes in the geographical distribution of fossils. During a glacial period cold-adapted organisms spread into lower latitudes, and organisms that prefer warmer conditions become extinct or are squeezed into lower latitudes. This evidence is also difficult to interpret because it requires (1) sequences of sediments covering a long period of time, over a wide range of latitudes and which are easily correlated; (2) ancient organisms which survive for several million years without change and whose temperature preferences are easily diagnosed; and (3) the finding of the relevant fossils.
Despite the difficulties, analyses of ice core and ocean sediment coreshas shown periods of glacials and interglacials over the past few million years. These also confirm the linkage between ice ages and continental crust phenomena such as glacial moraines, drumlins, and glacial erratics. Hence the continental crust phenomena are accepted as good evidence of earlier ice ages when they are found in layers created much earlier than the time range for which ice cores and ocean sediment cores are available.
Ice age - Wikipedia
Typical example of a valley formed by flowing water or a river valley.
Typical example of a valley formed by a glacier
notice the diference between the 2 one is V shaped and one is U shaped, now there is more evidence then just the shape of the vally to determine it was made by a glacier forgot some of it cause i learned this 15 years ago in primary school around the age of 10. And if you ever to happen to visit a country that still has some glaciers you can go and have a look at how they look like and you can see that they are making U shaped vallies.
And nowhere in the world rivers make those kind of vallies they make V shaped vallies.
So in one swoop i provided you whit evidence for ice ages and evidence that rivers cannot make and do not make U shaped valleys. Ergo ice ages happened and the flood could not have produced the valley features we see today.