diff --git a/dune/tectonic/frictionpotential.hh b/dune/tectonic/frictionpotential.hh
index 042ef2b3a5b061f85b57fa2610cf46f72a8ad836..909ccd5ec22229099873e891b55ed736ca5869ca 100644
--- a/dune/tectonic/frictionpotential.hh
+++ b/dune/tectonic/frictionpotential.hh
@@ -34,10 +34,10 @@ class FrictionPotential : public FrictionPotentialWrapper {
 
   double coefficientOfFriction(double V) const {
     assert(V >= 0.0);
-    if (V <= V_cutoff)
+    if (V <= Vmin)
       return 0.0;
 
-    return fd.a * (std::log(V) - logV_m);
+    return fd.a * (std::log(V) - logVmin);
   }
 
   double differential(double V) const {
@@ -46,7 +46,7 @@ class FrictionPotential : public FrictionPotentialWrapper {
 
   double second_deriv(double V) const {
     assert(V >= 0);
-    if (V <= V_cutoff)
+    if (V <= Vmin)
       return 0;
 
     return weight * (-normalStress) * (fd.a / V);
@@ -54,7 +54,7 @@ class FrictionPotential : public FrictionPotentialWrapper {
 
   double regularity(double V) const {
     assert(V >= 0);
-    if (std::abs(V - V_cutoff) < 1e-14) // TODO
+    if (std::abs(V - Vmin) < 1e-14) // TODO
       return std::numeric_limits<double>::infinity();
 
     return std::abs(second_deriv(V));
@@ -63,16 +63,16 @@ class FrictionPotential : public FrictionPotentialWrapper {
   void updateLogState(double logState) {
     double const tmp =
         (fd.mu0 + fd.b * (logState + std::log(fd.V0 / fd.L))) / fd.a;
-    logV_m = std::log(fd.V0) - tmp;
-    V_cutoff = fd.V0 / std::exp(tmp);
+    logVmin = std::log(fd.V0) - tmp;
+    Vmin = fd.V0 / std::exp(tmp);
   }
 
 private:
   FrictionData const fd;
   double const weight;
   double const normalStress;
-  double logV_m;
-  double V_cutoff; // velocity at which mu falls short of mumin
+  double logVmin;
+  double Vmin;
 };
 
 class TrivialFunction : public FrictionPotentialWrapper {