diff --git a/core/config/schema/core.data_types.schema.yml b/core/config/schema/core.data_types.schema.yml
index 4f6ef0c..da51c95 100644
--- a/core/config/schema/core.data_types.schema.yml
+++ b/core/config/schema/core.data_types.schema.yml
@@ -378,12 +378,12 @@ field_config_base:
       type: boolean
       label: 'Translatable'
     default_value:
-      type: field.[%parent.field_type].value
+      type: field.value.[%parent.field_type]
     default_value_callback:
       type: string
       label: 'Default value callback'
     settings:
-      type: field.[%parent.field_type].field_settings
+      type: field.field_settings.[%parent.field_type]
     third_party_settings:
       type: sequence
       label: 'Third party settings'
@@ -417,9 +417,23 @@ core.date_format.*:
       type: string
       label: 'Default language'
 
+# Generic field settings schemas.
+
+field.storage_settings.*:
+  type: mapping
+  label: 'Settings'
+
+field.field_settings.*:
+  type: mapping
+  label: 'Settings'
+
+field.value.*:
+  type: sequence
+  label: 'Default value'
+
 # Schema for the configuration of the String field type.
 
-field.string.storage_settings:
+field.storage_settings.string:
   type: mapping
   label: 'String settings'
   mapping:
@@ -427,11 +441,11 @@ field.string.storage_settings:
       type: integer
       label: 'Maximum length'
 
-field.string.field_settings:
-  type: sequence
+field.field_settings.string:
+  type: mapping
   label: 'String settings'
 
-field.string.value:
+field.value.string:
   type: sequence
   label: 'Default value'
   sequence:
@@ -444,15 +458,15 @@ field.string.value:
 
 # Schema for the configuration of the  String (long) field type.
 
-field.string_long.storage_settings:
-  type: field.string.storage_settings
+field.storage_settings.string_long:
+  type: field.storage_settings.string
   label: 'String (long) settings'
 
-field.string_long.field_settings:
-  type: field.string.field_settings
+field.field_settings.string_long:
+  type: field.field_settings.string
   label: 'String (long) settings'
 
-field.string_long.value:
+field.value.string_long:
   type: sequence
   label: 'Default value'
   sequence:
@@ -465,7 +479,7 @@ field.string_long.value:
 
 # Schema for the configuration of the URI field type.
 
-field.uri.storage_settings:
+field.storage_settings.uri:
   type: mapping
   label: 'URI settings'
   mapping:
@@ -473,11 +487,11 @@ field.uri.storage_settings:
       type: integer
       label: 'Maximum length'
 
-field.uri.field_settings:
-  type: sequence
+field.field_settings.uri:
+  type: mapping
   label: 'URI settings'
 
-field.uri.value:
+field.value.uri:
   type: sequence
   label: 'Default value'
   sequence:
@@ -490,15 +504,15 @@ field.uri.value:
 
 # Schema for the configuration of the Created field type.
 
-field.created.storage_settings:
-  type: sequence
+field.storage_settings.created:
+  type: mapping
   label: 'Created timestamp settings'
 
-field.created.field_settings:
-  type: sequence
+field.field_settings.created:
+  type: mapping
   label: 'Created timestamp settings'
 
-field.created.value:
+field.value.created:
   type: sequence
   label: 'Default value'
   sequence:
@@ -511,15 +525,15 @@ field.created.value:
 
 # Schema for the configuration of the Changed field type.
 
-field.changed.storage_settings:
-  type: sequence
+field.storage_settings.changed:
+  type: mapping
   label: 'Changed timestamp settings'
 
-field.changed.field_settings:
-  type: sequence
+field.field_settings.changed:
+  type: mapping
   label: 'Changed timestamp settings'
 
-field.changed.value:
+field.value.changed:
   type: sequence
   label: 'Default value'
   sequence:
@@ -532,7 +546,7 @@ field.changed.value:
 
 # Schema for the configuration of the Entity reference field type.
 
-field.entity_reference.storage_settings:
+field.storage_settings.entity_reference:
   type: mapping
   label: 'Entity reference settings'
   mapping:
@@ -540,7 +554,7 @@ field.entity_reference.storage_settings:
       type: string
       label: 'Type of item to reference'
 
-field.entity_reference.field_settings:
+field.field_settings.entity_reference:
   type: mapping
   label: 'Entity reference settings'
   mapping:
@@ -551,7 +565,7 @@ field.entity_reference.field_settings:
       type: entity_reference.[%parent.handler].handler_settings
       label: 'Reference method settings'
 
-field.entity_reference.value:
+field.value.entity_reference:
   type: sequence
   label: 'Default value'
   sequence:
@@ -567,7 +581,7 @@ field.entity_reference.value:
 
 # Schema for the configuration of the Boolean field type.
 
-field.boolean.storage_settings:
+field.storage_settings.boolean:
   type: mapping
   label: 'Boolean settings'
   mapping:
@@ -578,11 +592,11 @@ field.boolean.storage_settings:
       type: string
       label: 'Off label'
 
-field.boolean.field_settings:
+field.field_settings.boolean:
+  type: mapping
   label: 'Boolean settings'
-  type: sequence
 
-field.boolean.value:
+field.value.boolean:
   type: sequence
   label: 'Default value'
   sequence:
@@ -595,20 +609,15 @@ field.boolean.value:
 
 # Schema for the configuration of the Email field type.
 
-field.email.storage_settings:
-  type: sequence
+field.storage_settings.email:
+  type: mapping
   label: 'Email settings'
-  sequence:
-    - type: string
 
-field.email.field_settings:
-  type: sequence
+field.field_settings.email:
+  type: mapping
   label: 'Email settings'
-  sequence:
-    - type: string
-      label: 'Setting'
 
-field.email.value:
+field.value.email:
   type: sequence
   label: 'Default value'
   sequence:
@@ -621,16 +630,17 @@ field.email.value:
 
 # Schema for the configuration of the Integer field type.
 
-field.integer.storage_settings:
-  type: sequence
+field.storage_settings.integer:
+  type: mapping
   label: 'Integer settings'
-  sequence:
-    - type: string
-      label: 'setting'
+  mapping:
+    unsigned:
+      type: boolean
+      label: 'Unsigned'
 
-field.integer.field_settings:
+field.field_settings.integer:
   type: mapping
-  label: 'Integer'
+  label: 'Integer settings'
   mapping:
     min:
       type: integer
@@ -648,7 +658,7 @@ field.integer.field_settings:
       type: string
       label: 'Database storage size'
 
-field.integer.value:
+field.value.integer:
   type: sequence
   label: 'Default value'
   sequence:
@@ -661,7 +671,7 @@ field.integer.value:
 
 # Schema for the configuration of the Decimal field type.
 
-field.decimal.storage_settings:
+field.storage_settings.decimal:
   type: mapping
   label: 'Decimal settings'
   mapping:
@@ -672,9 +682,9 @@ field.decimal.storage_settings:
       type: integer
       label: 'Scale'
 
-field.decimal.field_settings:
+field.field_settings.decimal:
   type: mapping
-  label: 'Decimal'
+  label: 'Decimal settings'
   mapping:
     min:
       type: float
@@ -689,7 +699,7 @@ field.decimal.field_settings:
       type: string
       label: 'Suffix'
 
-field.decimal.value:
+field.value.decimal:
    type: sequence
    label: 'Default value'
    sequence:
@@ -702,16 +712,13 @@ field.decimal.value:
 
 # Schema for the configuration of the Float field type.
 
-field.float.storage_settings:
-  type: sequence
+field.storage_settings.float:
+  type: mapping
   label: 'Float settings'
-  sequence:
-    - type: string
-      label: 'setting'
 
-field.float.field_settings:
+field.field_settings.float:
   type: mapping
-  label: 'Float'
+  label: 'Float settings'
   mapping:
     min:
       type: float
@@ -726,7 +733,7 @@ field.float.field_settings:
       type: string
       label: 'Suffix'
 
-field.float.value:
+field.value.float:
   type: sequence
   label: 'Default value'
   sequence:
diff --git a/core/lib/Drupal/Core/Field/Entity/BaseFieldOverride.php b/core/lib/Drupal/Core/Field/Entity/BaseFieldOverride.php
index 9fbe75c..b6b2a3c 100644
--- a/core/lib/Drupal/Core/Field/Entity/BaseFieldOverride.php
+++ b/core/lib/Drupal/Core/Field/Entity/BaseFieldOverride.php
@@ -154,8 +154,12 @@ protected function getBaseFieldDefinition() {
    *   BaseFieldOverride::allowBundleRename() has not been called.
    */
   public function preSave(EntityStorageInterface $storage) {
-    // Set the default instance settings.
-    $this->settings += \Drupal::service('plugin.manager.field.field_type')->getDefaultFieldSettings($this->getType());
+    // Filter out unknown settings and make sure all settings are present, so
+    // that a complete field definition is passed to the various hooks and
+    // written to config.
+    $field_type_manager = \Drupal::service('plugin.manager.field.field_type');
+    $default_settings = $field_type_manager->getDefaultFieldSettings($this->getType());
+    $this->settings = array_intersect_key($this->settings, $default_settings) + $default_settings;
 
     // Call the parent's presave method to perform validate and calculate
     // dependencies.
diff --git a/core/modules/comment/config/schema/comment.schema.yml b/core/modules/comment/config/schema/comment.schema.yml
index 8b8c6a3..b835af0 100644
--- a/core/modules/comment/config/schema/comment.schema.yml
+++ b/core/modules/comment/config/schema/comment.schema.yml
@@ -56,16 +56,17 @@ comment.type.*:
       type: text
       label: 'Description'
 
-field.comment.storage_settings:
-  type: sequence
-  label: 'Settings'
-  sequence:
-    - type: string
-      label: 'Setting'
+field.storage_settings.comment:
+  type: mapping
+  label: 'Comment settings'
+  mapping:
+    comment_type:
+      label: 'Comment type'
+      type: string
 
-field.comment.value:
+field.value.comment:
   type: sequence
-  label: 'Settings'
+  label: 'Default value'
   sequence:
     - type: mapping
       label: 'Settings'
@@ -89,7 +90,7 @@ field.comment.value:
           type: integer
           label: 'Count'
 
-field.comment.field_settings:
+field.field_settings.comment:
   type: mapping
   label: 'Comment settings'
   mapping:
diff --git a/core/modules/datetime/config/schema/datetime.schema.yml b/core/modules/datetime/config/schema/datetime.schema.yml
index 3086164..f6bb3bd 100644
--- a/core/modules/datetime/config/schema/datetime.schema.yml
+++ b/core/modules/datetime/config/schema/datetime.schema.yml
@@ -1,6 +1,6 @@
 # Schema for the configuration files of the Datetime module.
 
-field.datetime.storage_settings:
+field.storage_settings.datetime:
   type: mapping
   label: 'Datetime settings'
   mapping:
@@ -8,23 +8,23 @@ field.datetime.storage_settings:
       type: string
       label: 'Date type'
 
-field.datetime.field_settings:
-  type: sequence
-  label: 'Settings'
-  sequence:
-    - type: string
+field.field_settings.datetime:
+  type: mapping
+  label: 'Datetime settings'
 
-field.datetime.value:
+field.value.datetime:
   type: sequence
   label: 'Default value'
   sequence:
-    - type: sequence
+    - type: mapping
       label: 'Default value'
-      sequence:
-        - type: string
-          label: 'Type'
-        - type: string
-          label: 'Value'
+      mapping:
+        default_date_type:
+          type: string
+          label: 'Default date type'
+        default_date:
+          type: string
+          label: 'Default date value'
 
 entity_view_display.field.datetime_default:
   type: entity_field_view_display_base
diff --git a/core/modules/field/config/schema/field.schema.yml b/core/modules/field/config/schema/field.schema.yml
index 184dc2f..429c929 100644
--- a/core/modules/field/config/schema/field.schema.yml
+++ b/core/modules/field/config/schema/field.schema.yml
@@ -25,7 +25,7 @@ field.storage.*.*:
       type: string
       label: 'Type'
     settings:
-      type: field.[%parent.type].storage_settings
+      type: field.storage_settings.[%parent.type]
     module:
       type: string
       label: 'Module'
diff --git a/core/modules/field/src/Entity/FieldConfig.php b/core/modules/field/src/Entity/FieldConfig.php
index 87f4400..a8d9c0a 100644
--- a/core/modules/field/src/Entity/FieldConfig.php
+++ b/core/modules/field/src/Entity/FieldConfig.php
@@ -138,9 +138,13 @@ public function preSave(EntityStorageInterface $storage) {
 
     $storage_definition = $this->getFieldStorageDefinition();
 
+    // Filter out unknown settings and make sure all settings are present, so
+    // that a complete field definition is passed to the various hooks and
+    // written to config.
+    $default_settings = $field_type_manager->getDefaultFieldSettings($storage_definition->type);
+    $this->settings = array_intersect_key($this->settings, $default_settings) + $default_settings;
+
     if ($this->isNew()) {
-      // Set the default field settings.
-      $this->settings += $field_type_manager->getDefaultFieldSettings($storage_definition->type);
       // Notify the entity storage.
       $entity_manager->getStorage($this->entity_type)->onFieldDefinitionCreate($this);
     }
@@ -155,8 +159,6 @@ public function preSave(EntityStorageInterface $storage) {
       if ($storage_definition->uuid() != $this->original->getFieldStorageDefinition()->uuid()) {
         throw new FieldException("Cannot change an existing field's storage.");
       }
-      // Set the default field settings.
-      $this->settings += $field_type_manager->getDefaultFieldSettings($storage_definition->type);
       // Notify the entity storage.
       $entity_manager->getStorage($this->entity_type)->onFieldDefinitionUpdate($this, $this->original);
     }
diff --git a/core/modules/field/src/Entity/FieldStorageConfig.php b/core/modules/field/src/Entity/FieldStorageConfig.php
index 6b89e38..9ae0fc4 100644
--- a/core/modules/field/src/Entity/FieldStorageConfig.php
+++ b/core/modules/field/src/Entity/FieldStorageConfig.php
@@ -253,6 +253,13 @@ public function preSave(EntityStorageInterface $storage) {
     // Clear the derived data about the field.
     unset($this->schema);
 
+    // Filter out unknown settings and make sure all settings are present, so
+    // that a complete field definition is passed to the various hooks and
+    // written to config.
+    $field_type_manager = \Drupal::service('plugin.manager.field.field_type');
+    $default_settings = $field_type_manager->getDefaultStorageSettings($this->type);
+    $this->settings = array_intersect_key($this->settings, $default_settings) + $default_settings;
+
     if ($this->isNew()) {
       $this->preSaveNew($storage);
     }
@@ -303,10 +310,6 @@ protected function preSaveNew(EntityStorageInterface $storage) {
     }
     $this->module = $field_type['provider'];
 
-    // Make sure all settings are present, so that a complete field
-    // definition is passed to the various hooks and written to config.
-    $this->settings += $field_type_manager->getDefaultStorageSettings($this->type);
-
     // Notify the entity manager.
     $entity_manager->onFieldStorageDefinitionCreate($this);
   }
@@ -333,7 +336,6 @@ public function calculateDependencies() {
   protected function preSaveUpdated(EntityStorageInterface $storage) {
     $module_handler = \Drupal::moduleHandler();
     $entity_manager = \Drupal::entityManager();
-    $field_type_manager = \Drupal::service('plugin.manager.field.field_type');
 
     // Some updates are always disallowed.
     if ($this->type != $this->original->type) {
@@ -343,10 +345,6 @@ protected function preSaveUpdated(EntityStorageInterface $storage) {
       throw new FieldException("Cannot change the entity type for an existing field storage.");
     }
 
-    // Make sure all settings are present, so that a complete field
-    // definition is passed to the various hooks and written to config.
-    $this->settings += $field_type_manager->getDefaultStorageSettings($this->type);
-
     // See if any module forbids the update by throwing an exception. This
     // invokes hook_field_storage_config_update_forbid().
     $module_handler->invokeAll('field_storage_config_update_forbid', array($this, $this->original));
diff --git a/core/modules/file/config/schema/file.schema.yml b/core/modules/file/config/schema/file.schema.yml
index 0babe38..b7303a1 100644
--- a/core/modules/file/config/schema/file.schema.yml
+++ b/core/modules/file/config/schema/file.schema.yml
@@ -22,7 +22,7 @@ file.settings:
           type: path
           label: 'Directory'
 
-field.file.storage_settings:
+field.storage_settings.file:
   type: base_entity_reference_field_settings
   label: 'File settings'
   mapping:
@@ -36,12 +36,9 @@ field.file.storage_settings:
       type: string
       label: 'Upload destination'
 
-field.file.value:
+field.value.file:
   type: sequence
   label: 'Default value'
-  sequence:
-    - type: string
-      label: 'Value'
 
 base_file_field_field_settings:
   type: mapping
@@ -59,7 +56,7 @@ base_file_field_field_settings:
       type: string
       label: 'Maximum upload size'
 
-field.file.field_settings:
+field.field_settings.file:
   type: base_file_field_field_settings
   label: 'File settings'
   mapping:
diff --git a/core/modules/image/config/schema/image.schema.yml b/core/modules/image/config/schema/image.schema.yml
index ef03075..af0dfee 100644
--- a/core/modules/image/config/schema/image.schema.yml
+++ b/core/modules/image/config/schema/image.schema.yml
@@ -83,15 +83,15 @@ image.settings:
       type: boolean
       label: 'Suppress the itok query string for image derivatives'
 
-field.image.storage_settings:
-  type: field.file.storage_settings
+field.storage_settings.image:
+  type: field.storage_settings.file
   label: 'Image settings'
   mapping:
     default_image:
       type: field_default_image
       label: 'Default value'
 
-field.image.field_settings:
+field.field_settings.image:
   type: base_file_field_field_settings
   label: 'Image settings'
   mapping:
@@ -117,28 +117,12 @@ field.image.field_settings:
       type: field_default_image
       label: 'Default value'
 
-field.image.value:
+field.value.image:
   type: sequence
   label: 'Default value'
   sequence:
-    - type: mapping
+    - type: field_default_image
       label: 'Default image'
-      mapping:
-        fid:
-          type: integer
-          label: 'File ID'
-        alt:
-          type: string
-          label: 'Alternative text'
-        title:
-          type: string
-          label: 'Title text'
-        width:
-          type: integer
-          label: 'Width'
-        height:
-          type: integer
-          label: 'Height'
 
 entity_view_display.field.image:
   type: entity_field_view_display_base
diff --git a/core/modules/options/config/schema/options.schema.yml b/core/modules/options/config/schema/options.schema.yml
index f0d444a..a0d2c2b 100644
--- a/core/modules/options/config/schema/options.schema.yml
+++ b/core/modules/options/config/schema/options.schema.yml
@@ -1,6 +1,6 @@
 # Schema for the configuration files of the Options module.
 
-field.list_integer.storage_settings:
+field.storage_settings.list_integer:
   type: mapping
   label: 'List (integer) settings'
   mapping:
@@ -21,12 +21,11 @@ field.list_integer.storage_settings:
       type: string
       label: 'Allowed values function'
 
-field.list_integer.field_settings:
-  label: 'List (integer)'
+field.field_settings.list_integer:
+  label: 'List (integer) settings'
   type: mapping
-  mapping: {  }
 
-field.list_integer.value:
+field.value.list_integer:
   type: sequence
   label: 'Default value'
   sequence:
@@ -37,7 +36,7 @@ field.list_integer.value:
           type: integer
           label: 'Value'
 
-field.list_float.storage_settings:
+field.storage_settings.list_float:
   type: mapping
   label: 'List (float) settings'
   mapping:
@@ -58,12 +57,11 @@ field.list_float.storage_settings:
       type: string
       label: 'Allowed values function'
 
-field.list_float.field_settings:
-  label: 'List (float)'
+field.field_settings.list_float:
+  label: 'List (float) settings'
   type: mapping
-  mapping: {  }
 
-field.list_float.value:
+field.value.list_float:
   type: sequence
   label: 'Default value'
   sequence:
@@ -74,7 +72,7 @@ field.list_float.value:
           type: string
           label: 'Value'
 
-field.list_string.storage_settings:
+field.storage_settings.list_string:
   type: mapping
   label: 'List (text) settings'
   mapping:
@@ -95,12 +93,11 @@ field.list_string.storage_settings:
       type: string
       label: 'Allowed values function'
 
-field.list_string.field_settings:
-  label: 'List (float)'
+field.field_settings.list_string:
+  label: 'List (text) settings'
   type: mapping
-  mapping: {  }
 
-field.list_string.value:
+field.value.list_string:
   type: sequence
   label: 'Default value'
   sequence:
diff --git a/core/modules/taxonomy/config/schema/taxonomy.schema.yml b/core/modules/taxonomy/config/schema/taxonomy.schema.yml
index e9aed2b..bd0bf73 100644
--- a/core/modules/taxonomy/config/schema/taxonomy.schema.yml
+++ b/core/modules/taxonomy/config/schema/taxonomy.schema.yml
@@ -39,7 +39,7 @@ taxonomy.vocabulary.*:
       sequence:
         - type: taxonomy.vocabulary.third_party.[%key]
 
-field.taxonomy_term_reference.storage_settings:
+field.storage_settings.taxonomy_term_reference:
   type: base_entity_reference_field_settings
   label: 'Taxonomy term reference settings'
   mapping:
@@ -60,7 +60,7 @@ field.taxonomy_term_reference.storage_settings:
               type: integer
               value: 'Parent'
 
-field.taxonomy_term_reference.field_settings:
+field.field_settings.taxonomy_term_reference:
   type: mapping
   label: 'Taxonomy term reference settings'
   mapping:
@@ -68,7 +68,7 @@ field.taxonomy_term_reference.field_settings:
       type: string
       label: 'Reference method'
 
-field.taxonomy_term_reference.value:
+field.value.taxonomy_term_reference:
   type: sequence
   label: 'Default values'
   sequence:
diff --git a/core/modules/text/config/schema/text.schema.yml b/core/modules/text/config/schema/text.schema.yml
index f211cbf..84beb56 100644
--- a/core/modules/text/config/schema/text.schema.yml
+++ b/core/modules/text/config/schema/text.schema.yml
@@ -8,7 +8,7 @@ text.settings:
       type: integer
       label: 'Default summary length'
 
-field.text.storage_settings:
+field.storage_settings.text:
   type: mapping
   label: 'Text (formatted) settings'
   mapping:
@@ -16,13 +16,11 @@ field.text.storage_settings:
       type: integer
       label: 'Maximum length'
 
-field.text.field_settings:
+field.field_settings.text:
   type: mapping
   label: 'Text (formatted) settings'
-  sequence:
-    - type: string
 
-field.text.value:
+field.value.text:
   type: sequence
   label: 'Default value'
   sequence:
@@ -36,17 +34,15 @@ field.text.value:
           type: string
           label: 'Text format'
 
-field.text_long.storage_settings:
+field.storage_settings.text_long:
   label: 'Text (formatted, long) settings'
   type: mapping
-  mapping: {  }
 
-field.text_long.field_settings:
+field.field_settings.text_long:
   label: 'Text (formatted, long) settings'
   type: mapping
-  mapping: {  }
 
-field.text_long.value:
+field.value.text_long:
   type: sequence
   label: 'Default value'
   sequence:
@@ -60,12 +56,11 @@ field.text_long.value:
           type: string
           label: 'Text format'
 
-field.text_with_summary.storage_settings:
+field.storage_settings.text_with_summary:
   label: 'Text (formatted, long, with summary) settings'
   type: mapping
-  mapping: {  }
 
-field.text_with_summary.field_settings:
+field.field_settings.text_with_summary:
   type: mapping
   label: 'Text (formatted, long, with summary) settings'
   mapping:
@@ -73,7 +68,7 @@ field.text_with_summary.field_settings:
       type: boolean
       label: 'Summary input'
 
-field.text_with_summary.value:
+field.value.text_with_summary:
   type: sequence
   label: 'Default value'
   sequence: