The evidence indicates that as a general proposition, recession of the ice sheet developed in a progressive “step-down pattern” of closely spaced ice margins, both laterally and vertically. This step-down pattern led to the oft repeated analogy that recession ice margin features are like “closely spaced rings in a slowly draining bathtub.” Examples of this step-down pattern are evident in many locations:
- In the Memphremagog Basin for the T4-T6 margins, as part of the receding hybrid margins.
- In the Missisquoi Basin with T4-T8 stagnant ice margin features giving way to Champlain Sea features at the marine limit
- In the northern Champlain Basin along the eastern foothills, notably with many Bedrock Grooves, stagnant ice deposits, and kame deltas, giving way to Fort Ann features.
- In the North Branch Lamoille Basin marked by progressively lower stagnant ice deposits(almost the entire spectrum of recessional ice margin elevations for all of Vermont, in one small basin!).
- At and near the mouth of the southeastern corner of the Winooski Basin mouth, with numerous Bedrock Grooves indicative of progressive development of ice marginal drainage at progressively lower levels, leading to drainage associated with the development of multiple levels of Lake Mansfield.
- Along the central to southern Champlain Basin foothills from the Winooski Basin southward to the mouth of the Vermont Valley, with closely spaced T4-T6 ice margin features, and local proglacial water bodies, giving way to Coveville features.
- Along the floor of the Vermont Valley, between Rutland and Bennington
- This step-down character is significant, but is punctuated by ice margin features suggestive of “stillstands,” the significance of which is discussed elsewhere.