Lawn Weed Identifaction
One of the common names of this plant is creeping charlie (Glechoma hederacea). It reproduces with runners as well as seed. It prefers shaded areas but will spread into sunny areas.
Herbicides kind of work but because this plant does not transport the material, they are not 100% affective. You will probable need to use a combination of controls to keep this plant under control. You may never eliminate it completely.
1. Pull it up by hand or use a dethatching rake
2. Spray herbicides in autumn when temperature is in the 60's or 70's.
3. plant shade tolerant grasses to out compete it.
4. Prune or use other techniques to reduce shaded areas.
Use the scientific name (Glechoma hederacea) to search on line to get more details on the biology of this plant and other ways of combatting it. Short of replacing your entire lawn, you may not get rid of it completely. Even if you did replace your lawn, this plant would most likely come back from its original source so I would not recommend that extreme.