doc(geo): add doc for georoam totalZoom apache/echarts#19837
diff --git a/en/api/events.md b/en/api/events.md
index 7008236..97741fb 100644
--- a/en/api/events.md
+++ b/en/api/events.md
@@ -257,6 +257,7 @@
     componentType: 'geo' | 'series',

     seriesId: string,

     zoom: number, // zoom ratio of roaming once

+    totalZoom: number, // accumulated zoom ratio

     originX: number,

     originY: number

 }

@@ -525,7 +526,7 @@
     // ...

 };

 chart.on('finished', function () {

-    // ...  

+    // ...

 });

 chart.setOption(option);

 ```

diff --git a/zh/api/events.md b/zh/api/events.md
index cb4f06b..c9d2208 100644
--- a/zh/api/events.md
+++ b/zh/api/events.md
@@ -255,6 +255,7 @@
     componentType: 'geo' | 'series',
     seriesId: string,
     zoom: number, // 单次缩放倍数
+    totalZoom: number, //累计缩放倍数
     originX: number,
     originY: number
 }
@@ -514,7 +515,7 @@
     // ...
 };
 chart.on('finished', function () {
-    // ...  
+    // ...
 });
 chart.setOption(option);
 ```