diff --git a/src/nshmp-lib/models/gmm/gmm-input.model.ts b/src/nshmp-lib/models/gmm/gmm-input.model.ts
index c569fa2afed06c5a36ce1a3e75653d8f26dffaad..8a8f2a69d5d6f9272a5867ce3cd41cbb572c7db4 100644
--- a/src/nshmp-lib/models/gmm/gmm-input.model.ts
+++ b/src/nshmp-lib/models/gmm/gmm-input.model.ts
@@ -5,7 +5,7 @@ export interface GmmInput {
   rX: number;
   dip: number;
   width: number;
-  zTop: number;
+  zTor: number;
   zHyp: number;
   rake: number;
   vs30: number;
diff --git a/src/nshmp-ws/models/gmm-services/gmm-usage.model.ts b/src/nshmp-ws/models/gmm-services/gmm-usage.model.ts
index d01e984811c7949d1087a9bbd9a21d07b0b71125..2e4393919f3ee427977f9a481f398385fd4bb302 100644
--- a/src/nshmp-ws/models/gmm-services/gmm-usage.model.ts
+++ b/src/nshmp-ws/models/gmm-services/gmm-usage.model.ts
@@ -108,7 +108,7 @@ export interface GmmUsageParameters {
   Mw: GmmUsageParameter;
   dip: GmmUsageParameter;
   width: GmmUsageParameter;
-  zTop: GmmUsageParameter;
+  zTor: GmmUsageParameter;
   zHyp: GmmUsageParameter;
   rake: GmmUsageParameter;
   vs30: GmmUsageParameter;